MQL5 MVC范式下的表格视图与控制器组件：可调整尺寸的元素
MetaTrader 5
—
示例
|
29
2
内容
引言
在现代用户界面中，鼠标拖动调整元素大小是一项十分常见且符合用户预期的功能。用户可以“抓取”窗口、面板或其他可视区域的边框并拖动，以实时改变元素尺寸。这类交互功能需要一套设计完善的架构，以保证界面响应及时，并正确处理所有事件。
构建复杂界面时，一种主流的架构方案是MVC（模型‑视图‑控制器）。在该模式中：
- 模型（Model）负责数据与逻辑；
- 视图（View）负责数据展示以及与用户的可视化交互；
- 控制器（Controller）负责处理用户事件，并在模型与视图之间进行通信。
在实现鼠标拖动调整元素大小的场景中，其核心工作主要在视图组件层面完成。视图负责元素的可视化呈现、追踪鼠标移动、判断光标是否位于边界上，并显示相应的提示（例如改变鼠标光标形状）。在拖动调整过程中，该组件还负责实时渲染已改变尺寸的元素。
控制器组件可以参与处理鼠标事件，向视图组件发送指令，并在需要时更新模型（例如需要保存元素尺寸，或尺寸变化会影响其他数据时）。
实现鼠标拖动调整大小，是MVC架构下视图组件的典型工作场景：视觉交互与用户反馈都尽可能通过直观的可视化交互来实现。
可视化表格（TableView、DataGrid、Spreadsheet等）是现代界面的核心控件之一，用于展示和编辑表格数据。用户期望表格不仅能显示数据，还能提供便捷的外观自定义工具，以适配自身的使用需求。
通过鼠标调整表格及其各组成部分大小（列宽、行高、整个表格区域尺寸），已成为专业软件中TableView控件的事实标准。具备此类功能可以：
- 根据数据量和结构适配界面。用户可拉宽包含长内容的列，或收窄无意义的列。
- 提升信息可读性与观感。灵活调整尺寸可避免横向滚动条和多余的空白区域。
- 营造更具“动态感”的界面体验，与办公软件、数据分析软件的使用习惯一致。
- 支持复杂的数据场景，实现单元格、行、列尺寸的动态变化。
如果不支持尺寸调整，TableView控件会显得静态僵化，难以满足实际的数据处理需求。因此，实现鼠标拖动调整元素大小的机制，是开发现代、易用、专业级表格控件不可或缺的一环。
今天，我们将为所有元素添加拖动边缘和角点调整大小的能力。实现时，光标区域会显示图形提示 —— 指示可拉伸方向的箭头。当鼠标悬停在可拖动区域并按下按下鼠标并占用该交互区域时，调整大小模式将被激活；松开鼠标时，该模式自动关闭。所有状态标记（调整大小模式是否激活、调整方向等）都会保存在共享资源类中，供每个图形元素读取。
我们将为所有图形元素加入调整大小的能力。
实现该功能只需修改已有的类，并新增一个用于创建提示框的类即可。提示框是一类特殊的图形元素：当鼠标悬停在元素的特定区域上，短暂延迟后会自动显示，内容可以是文字、图标或二者兼有。基于该类，我们还可以扩展其他提示框，例如，在光标附近显示箭头图标，指示元素的拉伸方向。
今天我们要实现的正是这类提示框：双向水平、垂直及对角箭头，用于指示图形元素边缘与角点的拖动方向。文字提示框可在后续完成TableView控件后实现，用于对单元格、列和表头进行视觉说明。
我们继续在位于\MQL5\Indicators\Tables\Controls\下的库文件中编写代码。所有文件的旧版本可在前一篇文章中获取。我们将对Base.mqh和Controls.mqh文件进行改进。
完善基类
打开Base.mqh文件，并添加提示框类的前置声明：
//+------------------------------------------------------------------+ //| Base.mqh | //| Copyright 2025, MetaQuotes Ltd. | //| https://www.mql5.com | //+------------------------------------------------------------------+ #property copyright "Copyright 2025, MetaQuotes Ltd." #property link "https://www.mql5.com" //+------------------------------------------------------------------+ //| Include libraries | //+------------------------------------------------------------------+ #include <Canvas\Canvas.mqh> // CCanvas class #include <Arrays\List.mqh> // CList class //--- Forward declaration of control element classes class CCounter; // Delay counter class class CAutoRepeat; // Event auto-repeat class class CImagePainter; // Image drawing class class CVisualHint; // Hint class class CLabel; // Text label class class CButton; // Simple button class class CButtonTriggered; // Two-position button class class CButtonArrowUp; // Up arrow button class class CButtonArrowDown; // Down arrow button class class CButtonArrowLeft; // Left arrow button class class CButtonArrowRight; // Right arrow button class class CCheckBox; // CheckBox control class class CRadioButton; // RadioButton control class class CScrollBarThumbH; // Horizontal scrollbar slider class class CScrollBarThumbV; // Vertical scrollbar slider class class CScrollBarH; // Horizontal scrollbar class class CScrollBarV; // Vertical scrollbar class class CPanel; // Panel control class class CGroupBox; // GroupBox control class class CContainer; // Container control class //+------------------------------------------------------------------+ //| Macro substitutions | //+------------------------------------------------------------------+
每个元素都应在其边缘设置一段特定区域，当鼠标指针悬停在该区域上时，即可激活对象的尺寸调整功能。请在宏定义块中添加该区域的厚度设置：
//+------------------------------------------------------------------+ //| Macro substitutions | //+------------------------------------------------------------------+ #define clrNULL 0x00FFFFFF // Transparent color for CCanvas #define MARKER_START_DATA -1 // Data start marker in a file #define DEF_FONTNAME "Calibri" // Default font #define DEF_FONTSIZE 10 // Default font size #define DEF_EDGE_THICKNESS 3 // Zone width to capture the border/corner //+------------------------------------------------------------------+ //| Enumerations | //+------------------------------------------------------------------+
在图形元素类型的枚举中，新增一种“提示对象”类型。
//+------------------------------------------------------------------+ //| Enumerations | //+------------------------------------------------------------------+ enum ENUM_ELEMENT_TYPE // Enumeration of graphical element types { ELEMENT_TYPE_BASE = 0x10000, // Basic object of graphical elements ELEMENT_TYPE_COLOR, // Color object ELEMENT_TYPE_COLORS_ELEMENT, // Color object of the graphical object element ELEMENT_TYPE_RECTANGLE_AREA, // Rectangular area of the element ELEMENT_TYPE_IMAGE_PAINTER, // Object for drawing images ELEMENT_TYPE_COUNTER, // Counter object ELEMENT_TYPE_AUTOREPEAT_CONTROL, // Event auto-repeat object ELEMENT_TYPE_CANVAS_BASE, // Basic canvas object for graphical elements ELEMENT_TYPE_ELEMENT_BASE, // Basic object of graphical elements ELEMENT_TYPE_HINT, // Tooltip ELEMENT_TYPE_LABEL, // Text label ELEMENT_TYPE_BUTTON, // Simple button ELEMENT_TYPE_BUTTON_TRIGGERED, // Two-position button ELEMENT_TYPE_BUTTON_ARROW_UP, // Up arrow button ELEMENT_TYPE_BUTTON_ARROW_DOWN, // Down arrow button ELEMENT_TYPE_BUTTON_ARROW_LEFT, // Left arrow button ELEMENT_TYPE_BUTTON_ARROW_RIGHT, // Right arrow button ELEMENT_TYPE_CHECKBOX, // CheckBox control ELEMENT_TYPE_RADIOBUTTON, // RadioButton control ELEMENT_TYPE_SCROLLBAR_THUMB_H, // Horizontal scroll bar slider ELEMENT_TYPE_SCROLLBAR_THUMB_V, // Vertical scroll bar slider ELEMENT_TYPE_SCROLLBAR_H, // ScrollBarHorisontal control ELEMENT_TYPE_SCROLLBAR_V, // ScrollBarVertical control ELEMENT_TYPE_PANEL, // Panel control ELEMENT_TYPE_GROUPBOX, // GroupBox control ELEMENT_TYPE_CONTAINER, // Container control }; #define ACTIVE_ELEMENT_MIN ELEMENT_TYPE_LABEL // Minimum value of the list of active elements #define ACTIVE_ELEMENT_MAX ELEMENT_TYPE_SCROLLBAR_V // Maximum value of the list of active elements
在调整元素大小的场景中，光标与控件的交互涉及一系列状态概念，例如光标位于元素的某条边框或某个角点上，以及当前正在执行的操作。
添加新的枚举类型，用于描述这些操作与状态值：
enum ENUM_CURSOR_REGION // Enumerate the cursor location on the element borders { CURSOR_REGION_NONE, // None CURSOR_REGION_TOP, // On the top border CURSOR_REGION_BOTTOM, // On the bottom border CURSOR_REGION_LEFT, // On the left border CURSOR_REGION_RIGHT, // On the right border CURSOR_REGION_LEFT_TOP, // In the upper left corner CURSOR_REGION_LEFT_BOTTOM, // In the lower left corner CURSOR_REGION_RIGHT_TOP, // In the upper right corner CURSOR_REGION_RIGHT_BOTTOM, // In the lower right corner }; enum ENUM_RESIZE_ZONE_ACTION // List interactions with the element dragging zone { RESIZE_ZONE_ACTION_NONE, // None RESIZE_ZONE_ACTION_HOVER, // Hovering the cursor over the zone RESIZE_ZONE_ACTION_BEGIN, // Start dragging RESIZE_ZONE_ACTION_DRAG, // Dragging RESIZE_ZONE_ACTION_END // Finish dragging }; //+------------------------------------------------------------------+ //| Functions | //+------------------------------------------------------------------+
光标与元素边界的交互分为五个关键阶段：
- 无交互。按常规方式处理元素事件。
- 光标悬停在可调整大小的区域上。应在光标旁显示箭头提示，指示可调整大小的方向。此处也可以设置一个全局标记，禁止其他元素响应鼠标交互事件。该功能目前暂未实现。
- 用户刚按下鼠标按键，捕获了图形元素的交互区域。设置激活拖动调整大小模式的公共标记，显示箭头提示，并在共享资源管理器中记录拖动方向。调用图形元素尺寸调整的处理函数。
- 用户按住并拖动元素边缘或角点。在全局资源管理器中设置拖动方向。根据该值调用尺寸调整处理函数，跟随光标持续显示箭头提示。
- 用户在调整模式下松开鼠标按键，共享资源管理器中所有已设置的标记被重置，箭头提示隐藏。元素在处理函数中完成尺寸修改，获得新的大小。
今天我们将实现这套逻辑。上述用于禁止其他元素响应鼠标的标记功能暂不实现，因为它更偏向辅助功能，主要用于简化边缘拖动时的交互处理。
例如，如果滚动条与元素下边缘相邻，当光标悬停在该边缘时，滚动条也可能响应交互。结果就会变成激活容器内容滚动，而非拖动边缘调整大小，因为滚动条会抢占控制权。话说回来，哪个成熟控件会没有可捕获的操作区域呢？大概只有像目前这样尚未完成的控件才会如此。实现这类辅助功能，会让本就复杂的图形元素类代码更加繁琐。
在根据类型返回元素简短名称的函数中，添加一个新的名称值：
//+------------------------------------------------------------------+ //| Return the short name of the element by type | //+------------------------------------------------------------------+ string ElementShortName(const ENUM_ELEMENT_TYPE type) { switch(type) { case ELEMENT_TYPE_ELEMENT_BASE : return "BASE"; // Basic object of graphical elements case ELEMENT_TYPE_HINT : return "HNT"; // Tooltip case ELEMENT_TYPE_LABEL : return "LBL"; // Text label case ELEMENT_TYPE_BUTTON : return "SBTN"; // Simple button case ELEMENT_TYPE_BUTTON_TRIGGERED : return "TBTN"; // Toggle button case ELEMENT_TYPE_BUTTON_ARROW_UP : return "BTARU"; // Up arrow button case ELEMENT_TYPE_BUTTON_ARROW_DOWN : return "BTARD"; // Down arrow button case ELEMENT_TYPE_BUTTON_ARROW_LEFT : return "BTARL"; // Left arrow button case ELEMENT_TYPE_BUTTON_ARROW_RIGHT: return "BTARR"; // Right arrow button case ELEMENT_TYPE_CHECKBOX : return "CHKB"; // CheckBox control case ELEMENT_TYPE_RADIOBUTTON : return "RBTN"; // RadioButton control case ELEMENT_TYPE_SCROLLBAR_THUMB_H : return "THMBH"; // Horizontal scroll bar slider case ELEMENT_TYPE_SCROLLBAR_THUMB_V : return "THMBV"; // Vertical scroll bar slider case ELEMENT_TYPE_SCROLLBAR_H : return "SCBH"; // ScrollBarHorisontal control case ELEMENT_TYPE_SCROLLBAR_V : return "SCBV"; // ScrollBarVertical control case ELEMENT_TYPE_PANEL : return "PNL"; // Panel control case ELEMENT_TYPE_GROUPBOX : return "GRBX"; // GroupBox control case ELEMENT_TYPE_CONTAINER : return "CNTR"; // Container control default : return "Unknown"; // Unknown } }
在共享资源管理器类中，添加用于获取并返回鼠标光标坐标、尺寸调整模式标记以及元素边缘（拖动方向）的功能：
//+------------------------------------------------------------------+ //| Singleton class for common flags and events of graphical elements| //+------------------------------------------------------------------+ class CCommonManager { private: static CCommonManager *m_instance; // Class instance string m_element_name; // Active element name int m_cursor_x; // X cursor coordinate int m_cursor_y; // Y cursor coordinate bool m_resize_mode; // Resize mode ENUM_CURSOR_REGION m_resize_region; // The edge of the element where the size is changed //--- Constructor/destructor CCommonManager(void) : m_element_name("") {} ~CCommonManager() {} public: //--- Method for getting a Singleton instance static CCommonManager *GetInstance(void) { if(m_instance==NULL) m_instance=new CCommonManager(); return m_instance; } //--- Method for destroying a Singleton instance static void DestroyInstance(void) { if(m_instance!=NULL) { delete m_instance; m_instance=NULL; } } //--- (1) Set and (2) return the name of the active current element void SetElementName(const string name) { this.m_element_name=name; } string ElementName(void) const { return this.m_element_name; } //--- (1) Set and (2) return the X cursor coordinate void SetCursorX(const int x) { this.m_cursor_x=x; } int CursorX(void) const { return this.m_cursor_x; } //--- (1) Set and (2) return the Y cursor coordinate void SetCursorY(const int y) { this.m_cursor_y=y; } int CursorY(void) const { return this.m_cursor_y; } //--- (1) Set and return (2) the resizing mode void SetResizeMode(const bool flag) { this.m_resize_mode=flag; } bool ResizeMode(void) const { return this.m_resize_mode; } //--- (1) Set and (2) return the element edge void SetResizeRegion(const ENUM_CURSOR_REGION edge){ this.m_resize_region=edge; } ENUM_CURSOR_REGION ResizeRegion(void) const { return this.m_resize_region;} }; //--- Initialize a static instance variable of a class CCommonManager* CCommonManager::m_instance=NULL;
在事件处理函数中，会将光标坐标写入类变量，从而在程序的任意位置均可访问，这简化了坐标的获取与在控件中的使用。同理，通过将尺寸调整模式标记以及光标交互的元素边缘位置写入变量，我们可以让所有元素都能“感知”到当前模式，并做出相应处理。
对图形元素画布的基类进行改进。声明一个标记，用于标识该元素支持交互式尺寸修改：
//+------------------------------------------------------------------+ //| Base class of graphical elements canvas | //+------------------------------------------------------------------+ class CCanvasBase : public CBaseObj { private: bool m_chart_mouse_wheel_flag; // Flag for sending mouse wheel scroll messages bool m_chart_mouse_move_flag; // Flag for sending mouse cursor movement messages bool m_chart_object_create_flag; // Flag for sending messages about the graphical object creation event bool m_chart_mouse_scroll_flag; // Flag for scrolling the chart with the left button and mouse wheel bool m_chart_context_menu_flag; // Flag of access to the context menu using the right click bool m_chart_crosshair_tool_flag; // Flag of access to the Crosshair tool using the middle click bool m_flags_state; // State of the flags for scrolling the chart with the wheel, the context menu, and the crosshair //--- Set chart restrictions (wheel scrolling, context menu, and crosshair) void SetFlags(const bool flag); protected: CCanvas m_background; // Background canvas CCanvas m_foreground; // Foreground canvas CBound m_bound; // Object boundaries CCanvasBase *m_container; // Parent container object CColorElement m_color_background; // Background color control object CColorElement m_color_foreground; // Foreground color control object CColorElement m_color_border; // Border color control object CColorElement m_color_background_act; // Activated element background color control object CColorElement m_color_foreground_act; // Activated element foreground color control object CColorElement m_color_border_act; // Activated element frame color control object CAutoRepeat m_autorepeat; // Event auto-repeat control object ENUM_ELEMENT_STATE m_state; // Control state (e.g. buttons (on/off)) long m_chart_id; // Chart ID int m_wnd; // Chart subwindow index int m_wnd_y; // Cursor Y coordinate offset in the subwindow int m_obj_x; // Graphical object X coordinate int m_obj_y; // Graphical object Y coordinate uchar m_alpha_bg; // Background transparency uchar m_alpha_fg; // Foreground transparency uint m_border_width_lt; // Left frame width uint m_border_width_rt; // Right frame width uint m_border_width_up; // Top frame width uint m_border_width_dn; // Bottom frame width string m_program_name; // Program name bool m_hidden; // Hidden object flag bool m_blocked; // Blocked element flag bool m_movable; // Moved element flag bool m_resizable; // Resizing flag bool m_focused; // Element flag in focus bool m_main; // Main object flag bool m_autorepeat_flag; // Event sending auto-repeat flag bool m_scroll_flag; // Flag for scrolling content using scrollbars bool m_trim_flag; // Flag for clipping the element to the container borders int m_cursor_delta_x; // Distance from the cursor to the left edge of the element int m_cursor_delta_y; // Distance from the cursor to the top edge of the element int m_z_order; // Graphical object Z-order
添加用于从共享资源管理器中设置和读取尺寸调整模式标记以及交互区域的方法：
//--- (1) Set, return (2) the name and (3) the active element flag void SetActiveElementName(const string name) { CCommonManager::GetInstance().SetElementName(name); } string ActiveElementName(void) const { return CCommonManager::GetInstance().ElementName(); } bool IsCurrentActiveElement(void) const { return this.ActiveElementName()==this.NameFG(); } //--- (1) Set and (2) return the resize mode flag void SetResizeMode(const bool flag) { CCommonManager::GetInstance().SetResizeMode(flag); } bool ResizeMode(void) const { return CCommonManager::GetInstance().ResizeMode(); } //--- (1) Set and (2) return the element edge, above which the size is changed void SetResizeRegion(const ENUM_CURSOR_REGION edge){ CCommonManager::GetInstance().SetResizeRegion(edge); } ENUM_CURSOR_REGION ResizeRegion(void) const { return CCommonManager::GetInstance().ResizeRegion(); } //--- Return the offset of the initial drawing coordinates on the canvas relative to the canvas and the object coordinates
现在，每个图形元素都可以设置和读取所有元素共用的尺寸调整模式相关数据。
当通过拖动左侧或顶部边缘，以及与这些边缘相邻的角点来调整元素大小时，必须在改变尺寸的同时同步移动坐标。测试表明，如果先后分别调用“移动坐标”和“调整尺寸”两个独立方法，在两次方法调用之间，交易平台可能会触发图表刷新与重绘。这样会导致在拖动边缘调整大小时，图表上出现视觉瑕疵 —— 比如元素会闪烁显示之前未改变的旧尺寸。
为避免这种影响观感的问题，需要缩短调整尺寸与移动坐标之间的时间间隔。为此，实现（声明）一个独立的方法，在该方法中同时直接修改元素的尺寸与坐标：
//--- Set the graphical object (1) X, (2) Y and (3) both coordinates bool ObjectSetX(const int x); bool ObjectSetY(const int y); bool ObjectSetXY(const int x,const int y) { return(this.ObjectSetX(x) && this.ObjectSetY(y)); } //--- Set both the coordinates and dimensions of a graphical object virtual bool ObjectSetXYWidthResize(const int x,const int y,const int w,const int h);
我们需要一个方法，用于返回光标在图形元素边界内的所处位置。声明这样的方法：
//--- (1) Set and (2) relocate the graphical object by the specified coordinates/offset size bool ObjectMove(const int x,const int y) { return this.ObjectSetXY(x,y); } bool ObjectShift(const int dx,const int dy) { return this.ObjectSetXY(this.ObjectX()+dx,this.ObjectY()+dy); } //--- Returns the flag indicating whether the cursor is inside the object bool Contains(const int x,const int y); //--- Return the cursor location on the object borders ENUM_CURSOR_REGION CheckResizeZone(const int x,const int y);
声明虚函数处理程序，用于响应元素边界上的光标交互事件以实现尺寸调整：
//--- Cursor hovering (Focus), (2) button click (Press), //--- (3) cursor moving (Move), (4) leaving focus (Release), (5) graphical object creation (Create), //--- (6) wheel scrolling (Wheel) and (7) resizing (Resize) event handlers. Redefined in descendants. virtual void OnFocusEvent(const int id, const long lparam, const double dparam, const string sparam); virtual void OnPressEvent(const int id, const long lparam, const double dparam, const string sparam); virtual void OnMoveEvent(const int id, const long lparam, const double dparam, const string sparam); virtual void OnReleaseEvent(const int id, const long lparam, const double dparam, const string sparam); virtual void OnCreateEvent(const int id, const long lparam, const double dparam, const string sparam); virtual void OnWheelEvent(const int id, const long lparam, const double dparam, const string sparam) { return; } // handler is disabled here virtual void OnResizeZoneEvent(const int id, const long lparam, const double dparam, const string sparam) { return; } // handler is disabled here //--- Handlers for resizing the element by sides and corners virtual bool OnResizeZoneLeft(const int x, const int y) { return false; } // handler is disabled here virtual bool OnResizeZoneRight(const int x, const int y) { return false; } // handler is disabled here virtual bool OnResizeZoneTop(const int x, const int y) { return false; } // handler is disabled here virtual bool OnResizeZoneBottom(const int x, const int y) { return false; } // handler is disabled here virtual bool OnResizeZoneLeftTop(const int x, const int y) { return false; } // handler is disabled here virtual bool OnResizeZoneRightTop(const int x, const int y) { return false; } // handler is disabled here virtual bool OnResizeZoneLeftBottom(const int x, const int y) { return false; } // handler is disabled here virtual bool OnResizeZoneRightBottom(const int x, const int y) { return false; } // handler is disabled here
我们将在继承类中实现这些处理函数。
添加用于返回若干对象标记的方法，这些标记此前尚未实现：
//--- Return (1) the object's belonging to the program, the flag (2) of a hidden element, (3) a blocked element, //--- (4) moved, (5) resized, (6) main element, (7) in focus, (8, 9) graphical object name (background, text) bool IsBelongsToThis(const string name) const { return(::ObjectGetString(this.m_chart_id,name,OBJPROP_TEXT)==this.m_program_name);} bool IsHidden(void) const { return this.m_hidden; } bool IsBlocked(void) const { return this.m_blocked; } bool IsMovable(void) const { return this.m_movable; } bool IsResizable(void) const { return this.m_resizable; } bool IsMain(void) const { return this.m_main; } bool IsFocused(void) const { return this.m_focused; } bool IsAutorepeat(void) const { return this.m_autorepeat_flag; } bool IsScrollable(void) const { return this.m_scroll_flag; } bool IsTrimmed(void) const { return this.m_trim_flag; } string NameBG(void) const { return this.m_background.ChartObjectName(); } string NameFG(void) const { return this.m_foreground.ChartObjectName(); }
以及用于设置这些标记的方法：
//--- Set (1) movability, (2) main object flag for the object and (3) resizability void SetMovable(const bool flag) { this.m_movable=flag; } void SetAsMain(void) { this.m_main=true; } virtual void SetResizable(const bool flag) { this.m_resizable=flag; } void SetAutorepeat(const bool flag) { this.m_autorepeat_flag=flag; } void SetScrollable(const bool flag) { this.m_scroll_flag=flag; } void SetTrimmered(const bool flag) { this.m_trim_flag=flag; }
声明一个同时调整元素大小并将其移动到新坐标的方法：
//--- Set the new (1) X, (2) Y, (3) XY coordinate for the object virtual bool MoveX(const int x); virtual bool MoveY(const int y); virtual bool Move(const int x,const int y); //--- Set both the element coordinates and dimensions virtual bool MoveXYWidthResize(const int x,const int y,const int w,const int h);
在类的构造函数初始化列表中，为元素的尺寸调整标记设置默认值：
//--- Constructors/destructor CCanvasBase(void) : m_program_name(::MQLInfoString(MQL_PROGRAM_NAME)), m_chart_id(::ChartID()), m_wnd(0), m_alpha_bg(0), m_alpha_fg(255), m_hidden(false), m_blocked(false), m_focused(false), m_movable(false), m_resizable(false), m_main(false), m_autorepeat_flag(false), m_trim_flag(true), m_scroll_flag(false), m_border_width_lt(0), m_border_width_rt(0), m_border_width_up(0), m_border_width_dn(0), m_z_order(0), m_state(0), m_wnd_y(0), m_cursor_delta_x(0), m_cursor_delta_y(0) { this.Init(); } CCanvasBase(const string object_name,const long chart_id,const int wnd,const int x,const int y,const int w,const int h); ~CCanvasBase(void); }; //+------------------------------------------------------------------+ //| CCanvasBase::Constructor | //+------------------------------------------------------------------+ CCanvasBase::CCanvasBase(const string object_name,const long chart_id,const int wnd,const int x,const int y,const int w,const int h) : m_program_name(::MQLInfoString(MQL_PROGRAM_NAME)), m_wnd(wnd<0 ? 0 : wnd), m_alpha_bg(0), m_alpha_fg(255), m_hidden(false), m_blocked(false), m_focused(false), m_movable(false), m_resizable(false), m_main(false), m_autorepeat_flag(false), m_trim_flag(true), m_scroll_flag(false), m_border_width_lt(0), m_border_width_rt(0), m_border_width_up(0), m_border_width_dn(0), m_z_order(0), m_state(0), m_cursor_delta_x(0), m_cursor_delta_y(0) { //--- Get the adjusted chart ID and the distance in pixels along the vertical Y axis //--- between the upper frame of the indicator subwindow and the upper frame of the chart main window this.m_chart_id=this.CorrectChartID(chart_id); //--- If the graphical resource and graphical object are created if(this.Create(this.m_chart_id,this.m_wnd,object_name,x,y,w,h)) { //--- Clear the background and foreground canvases and set the initial coordinate values, //--- names of graphic objects and properties of text drawn in the foreground this.Clear(false); this.m_obj_x=x; this.m_obj_y=y; this.m_color_background.SetName("Background"); this.m_color_foreground.SetName("Foreground"); this.m_color_border.SetName("Border"); this.m_foreground.FontSet(DEF_FONTNAME,-DEF_FONTSIZE*10,FW_MEDIUM); this.m_bound.SetName("Perimeter"); //--- Remember permissions for the mouse and chart tools this.Init(); } }
在类体外，实现已声明的这些方法。
返回光标在对象边界上位置的方法：
//+--------------------------------------------------------------------+ //|CCanvasBase::Return the cursor location on the object borders | //+--------------------------------------------------------------------+ ENUM_CURSOR_REGION CCanvasBase::CheckResizeZone(const int x,const int y) { //--- Coordinates of the element borders int top=this.Y(); int bottom=this.Bottom(); int left=this.X(); int right=this.Right(); //--- If outside the object, return CURSOR_REGION_NONE if(x<left || x>right || y<top || y>bottom) return CURSOR_REGION_NONE; //--- Left edge and corners if(x>=left && x<=left+DEF_EDGE_THICKNESS) { //--- Upper left corner if(y>=top && y<=top+DEF_EDGE_THICKNESS) return CURSOR_REGION_LEFT_TOP; //--- Bottom left corner if(y>=bottom-DEF_EDGE_THICKNESS && y<=bottom) return CURSOR_REGION_LEFT_BOTTOM; //--- Left edge return CURSOR_REGION_LEFT; } //--- Right edge and corners if(x>=right-DEF_EDGE_THICKNESS && x<=right) { //--- Upper right corner if(y>=top && y<=top+DEF_EDGE_THICKNESS) return CURSOR_REGION_RIGHT_TOP; //--- Bottom right corner if(y>=bottom-DEF_EDGE_THICKNESS && y<=bottom) return CURSOR_REGION_RIGHT_BOTTOM; //--- Right side return CURSOR_REGION_RIGHT; } //--- Upper edge if(y>=top && y<=top+DEF_EDGE_THICKNESS) return CURSOR_REGION_TOP; //--- Bottom edge if(y>=bottom-DEF_EDGE_THICKNESS && y<=bottom) return CURSOR_REGION_BOTTOM; //--- The cursor is not on the edges of the element return CURSOR_REGION_NONE; }
该方法用于检测光标是否位于元素边界周围、宽度为DEF\_EDGE\_THICKNESS的窄边区域内，并返回光标所处的边框或角点位置。
同时设置图形对象坐标与尺寸的方法：
//+------------------------------------------------------------------+ //| CCanvasBase::Set coordinates | //| and size of the graphical object simultaneously | //+------------------------------------------------------------------+ bool CCanvasBase::ObjectSetXYWidthResize(const int x,const int y,const int w,const int h) { //--- If new coordinates are set, return the resize result if(this.ObjectSetXY(x,y)) return this.ObjectResize(w,h); //--- Failed to set new coordinates - return 'false' return false; }
如果对象坐标设置成功，则返回图形对象调整尺寸后的结果。该方法内部调用的子方法会直接访问图形对象的属性，因此相比分别调用“调整尺寸”和“移动坐标”的独立方法，延迟更低，因为那些独立方法还会额外执行其他属性相关操作。
同时设置元素坐标与尺寸的方法：
//+------------------------------------------------------------------+ //| CCanvasBase::Set both the element coordinates and dimensions | //+------------------------------------------------------------------+ bool CCanvasBase::MoveXYWidthResize(const int x,const int y,const int w,const int h) { if(!this.ObjectSetXYWidthResize(x,y,w,h)) return false; this.BoundMove(x,y); this.BoundResize(w,h); if(!this.ObjectTrim()) { this.Update(false); this.Draw(false); } return true; }
首先，调用同时设置图形对象坐标与尺寸的方法；随后，再设置图形元素的各项属性；接下来，将元素按其容器大小进行裁剪。
完善事件处理函数，使其能够处理已允许鼠标光标调整大小的元素。在处理新建图形对象时，这类事件应当仅由容器类元素处理。这里，我们将光标坐标写入资源管理器：
//+------------------------------------------------------------------+ //| CCanvasBase::Event handler | //+------------------------------------------------------------------+ void CCanvasBase::OnChartEvent(const int id,const long& lparam,const double& dparam,const string& sparam) { //--- Chart change event if(id==CHARTEVENT_CHART_CHANGE) { //--- adjust the distance between the upper frame of the indicator subwindow and the upper frame of the chart main window this.m_wnd_y=(int)::ChartGetInteger(this.m_chart_id,CHART_WINDOW_YDISTANCE,this.m_wnd); } //--- Graphical object creation event if(id==CHARTEVENT_OBJECT_CREATE) { //--- If this is not a container element, leave if(this.Type()<ELEMENT_TYPE_PANEL) return; //--- Call the handler for creating the graphical object this.OnCreateEvent(id,lparam,dparam,sparam); } //--- If the element is blocked or hidden, leave if(this.IsBlocked() || this.IsHidden()) return; //--- Mouse cursor coordinates int x=(int)lparam; int y=(int)dparam-this.m_wnd_y; // Adjust Y by the height of the indicator window //--- Cursor move event if(id==CHARTEVENT_MOUSE_MOVE) { //--- Send the cursor coordinates to the resource manager CCommonManager::GetInstance().SetCursorX(x); CCommonManager::GetInstance().SetCursorY(y); //--- Do not handle inactive elements, except for the main one if(!this.IsMain() && (this.Type()<ACTIVE_ELEMENT_MIN || this.Type()>ACTIVE_ELEMENT_MAX)) return; //--- Hold down the mouse button if(sparam=="1") { //--- Cursor within the object if(this.Contains(x, y)) { //--- If this is the main object, disable the chart tools if(this.IsMain()) this.SetFlags(false); //--- If the mouse button was clicked on the chart, there is nothing to handle, leave if(this.ActiveElementName()=="Chart") return; //--- Fix the name of the active element over which the cursor was when the mouse button was clicked this.SetActiveElementName(this.ActiveElementName()); //--- If this is the current active element, handle its movement if(this.IsCurrentActiveElement()) { this.OnMoveEvent(id,lparam,dparam,sparam); //--- If the element has auto-repeat events active, indicate that the button is clicked if(this.m_autorepeat_flag) this.m_autorepeat.OnButtonPress(); //--- For resizable elements if(this.m_resizable) { //--- If the resize mode is not activated, //--- call the resize start handler if(!this.ResizeMode()) this.OnResizeZoneEvent(RESIZE_ZONE_ACTION_BEGIN,x,y,this.NameFG()); //--- otherwise, when the resizing mode is active //--- call the edge dragging handler for resizing else this.OnResizeZoneEvent(RESIZE_ZONE_ACTION_DRAG,x,y,this.NameFG()); } } } //--- Cursor outside the object else { //--- If this is the active main object, or the mouse button is clicked on the chart, and this is not the resizing mode, enable graphical tools if(this.IsMain() && (this.ActiveElementName()==this.NameFG() || this.ActiveElementName()=="Chart")) if(!this.ResizeMode()) this.SetFlags(true); //--- If this is the current active element if(this.IsCurrentActiveElement()) { //--- If the element is not movable if(!this.IsMovable()) { //--- call the mouse hover handler this.OnFocusEvent(id,lparam,dparam,sparam); //--- If the element has auto-repeat events active, indicate that the button is released if(this.m_autorepeat_flag) this.m_autorepeat.OnButtonRelease(); } //--- If the element is movable, call the move handler else this.OnMoveEvent(id,lparam,dparam,sparam); //--- For resizable elements //--- call the edge dragging handler for resizing if(this.m_resizable) this.OnResizeZoneEvent(RESIZE_ZONE_ACTION_DRAG,x,y,this.NameFG()); } } } //--- Mouse button not pressed else { //--- Cursor within the object if(this.Contains(x, y)) { //--- If this is the main element, disable the chart tools if(this.IsMain()) this.SetFlags(false); //--- Call the cursor hover handler and //--- set the element as the current active one this.OnFocusEvent(id,lparam,dparam,sparam); this.SetActiveElementName(this.NameFG()); //--- For resizable elements //--- call the handler for hovering the cursor over the resizing area if(this.m_resizable) this.OnResizeZoneEvent(RESIZE_ZONE_ACTION_HOVER,x,y,this.NameFG()); } //--- Cursor outside the object else { //--- If this is the main object if(this.IsMain()) { //--- Enable chart tools and //--- set the chart as the currently active element this.SetFlags(true); this.SetActiveElementName("Chart"); } //--- Call the handler for removing the cursor from focus this.OnReleaseEvent(id,lparam,dparam,sparam); //--- For resizable elements //--- call the handler for the non-resizing mode if(this.m_resizable) this.OnResizeZoneEvent(RESIZE_ZONE_ACTION_NONE,x,y,this.NameFG()); } } } //--- Event of clicking the mouse button on an object (releasing the button) if(id==CHARTEVENT_OBJECT_CLICK) { //--- If the click (releasing the mouse button) was performed on this object if(sparam==this.NameFG()) { //--- Call the mouse click handler and release the current active object this.OnPressEvent(id, lparam, dparam, sparam); this.SetActiveElementName(""); //--- If the element has auto-repeat events active, indicate that the button is released if(this.m_autorepeat_flag) this.m_autorepeat.OnButtonRelease(); //--- For resizable elements if(this.m_resizable) { //--- Disable the resizing mode, reset the interaction area, //--- call the handler for completing the resizing by dragging the edges this.SetResizeMode(false); this.SetResizeRegion(CURSOR_REGION_NONE); this.OnResizeZoneEvent(RESIZE_ZONE_ACTION_END,x,y,this.NameFG()); } } } //--- Mouse wheel scroll event if(id==CHARTEVENT_MOUSE_WHEEL) { if(this.IsCurrentActiveElement()) this.OnWheelEvent(id,lparam,dparam,sparam); } //--- If a custom chart event has arrived if(id>CHARTEVENT_CUSTOM) { //--- do not handle its own events if(sparam==this.NameFG()) return; //--- bring the custom event in line with the standard ones ENUM_CHART_EVENT chart_event=ENUM_CHART_EVENT(id-CHARTEVENT_CUSTOM); //--- In case of the mouse click on the object, call the user event handler if(chart_event==CHARTEVENT_OBJECT_CLICK) { this.MousePressHandler(chart_event, lparam, dparam, sparam); } //--- If the mouse cursor is moving, call the user event handler if(chart_event==CHARTEVENT_MOUSE_MOVE) { this.MouseMoveHandler(chart_event, lparam, dparam, sparam); } //--- In case of scrolling the mouse wheel, call the user event handler if(chart_event==CHARTEVENT_MOUSE_WHEEL) { this.MouseWheelHandler(chart_event, lparam, dparam, sparam); } //--- If the graphical element changes, call the user event handler if(chart_event==CHARTEVENT_OBJECT_CHANGE) { this.ObjectChangeHandler(chart_event, lparam, dparam, sparam); } } }
处理程序会在不同场景下调用对应的尺寸调整虚函数，具体逻辑均在这些函数中实现。我们将在后续的控件类中编写这些处理函数。
至此，我们完成了对基类的完善。现在，打开Controls.mqh图形元素类文件，并对其进行必要修改。
由于控件支持手动调整大小，需要设置最小尺寸限制。提示框类将支持创建不同类型的提示效果。为区分提示框，可编写一个专用枚举：
//+------------------------------------------------------------------+ //| Controls.mqh | //| Copyright 2025, MetaQuotes Ltd. | //| https://www.mql5.com | //+------------------------------------------------------------------+ #property copyright "Copyright 2025, MetaQuotes Ltd." #property link "https://www.mql5.com" //+------------------------------------------------------------------+ //| Include libraries | //+------------------------------------------------------------------+ #include "Base.mqh" //+------------------------------------------------------------------+ //| Macro substitutions | //+------------------------------------------------------------------+ #define DEF_LABEL_W 50 // Text label default width #define DEF_LABEL_H 16 // Text label default height #define DEF_BUTTON_W 60 // Default button width #define DEF_BUTTON_H 16 // Default button height #define DEF_PANEL_W 80 // Default panel width #define DEF_PANEL_H 80 // Default panel height #define DEF_PANEL_MIN_W 60 // Minimum panel width #define DEF_PANEL_MIN_H 60 // Minimum panel height #define DEF_SCROLLBAR_TH 13 // Default scrollbar width #define DEF_THUMB_MIN_SIZE 8 // Minimum width of the scrollbar slider #define DEF_AUTOREPEAT_DELAY 500 // Delay before launching auto-repeat #define DEF_AUTOREPEAT_INTERVAL 100 // Auto-repeat frequency //+------------------------------------------------------------------+ //| Enumerations | //+------------------------------------------------------------------+ enum ENUM_ELEMENT_SORT_BY // Compared properties { ELEMENT_SORT_BY_ID = BASE_SORT_BY_ID, // Comparison by element ID ELEMENT_SORT_BY_NAME = BASE_SORT_BY_NAME, // Comparison by element name ELEMENT_SORT_BY_X = BASE_SORT_BY_X, // Comparison by element X coordinate ELEMENT_SORT_BY_Y = BASE_SORT_BY_Y, // Comparison by element Y coordinate ELEMENT_SORT_BY_WIDTH= BASE_SORT_BY_WIDTH, // Comparison by element width ELEMENT_SORT_BY_HEIGHT= BASE_SORT_BY_HEIGHT, // Comparison by element height ELEMENT_SORT_BY_ZORDER= BASE_SORT_BY_ZORDER, // Comparison by element Z-order ELEMENT_SORT_BY_TEXT, // Comparison by element text ELEMENT_SORT_BY_COLOR_BG, // Comparison by element background color ELEMENT_SORT_BY_ALPHA_BG, // Comparison by element background transparency ELEMENT_SORT_BY_COLOR_FG, // Comparison by element foreground color ELEMENT_SORT_BY_ALPHA_FG, // Comparison by element foreground transparency color ELEMENT_SORT_BY_STATE, // Comparison by element state ELEMENT_SORT_BY_GROUP, // Comparison by element group }; enum ENUM_HINT_TYPE // Hint types { HINT_TYPE_TOOLTIP, // Tooltip HINT_TYPE_ARROW_HORZ, // Double horizontal arrow HINT_TYPE_ARROW_VERT, // Double vertical arrow HINT_TYPE_ARROW_NWSE, // Double arrow top-left --- bottom-right (NorthWest-SouthEast) HINT_TYPE_ARROW_NESW, // Double arrow bottom-left --- top-right (NorthEast-SouthWest) };
提示框类
提示框对象类将绘制不同样式的箭头，用于指示拖动元素边界进行尺寸调整的方向。系统中已有专门的CImagePainter类负责各类图像绘制。
为其添加（声明）用于绘制提示箭头的方法：
//--- Clear the area bool Clear(const int x,const int y,const int w,const int h,const bool update=true); //--- Draw a filled (1) up, (2) down, (3) left and (4) right arrow bool ArrowUp(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true); bool ArrowDown(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true); bool ArrowLeft(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true); bool ArrowRight(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true); //--- Draw (1) horizontal 17х7 and (2) vertical 7х17 double arrow bool ArrowHorz(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true); bool ArrowVert(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true); //--- Draw a diagonal (1) top-left --- bottom-right and (2) bottom-left --- up-right 17x17 double arrow bool ArrowNWSE(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true); bool ArrowNESW(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true); //--- Draw (1) checked and (2) unchecked CheckBox bool CheckedBox(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true); bool UncheckedBox(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true);
在类的外部，编写这些新声明方法的具体实现：
//+------------------------------------------------------------------+ //| CImagePainter::Draw a horizontal 17x7 double arrow | //+------------------------------------------------------------------+ bool CImagePainter::ArrowHorz(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true) { //--- If the image area is not valid, return 'false' if(!this.CheckBound()) return false; //--- Shape coordinates int arrx[15]={0, 3, 4, 4, 12, 12, 13, 16, 13, 12, 12, 4, 4, 3, 0}; int arry[15]={3, 0, 0, 2, 2, 0, 0, 3, 6, 6, 4, 4, 6, 6, 3}; //--- Draw the white background this.m_canvas.Polyline(arrx,arry,::ColorToARGB(clrWhite,alpha)); //--- Draw the line of arrows this.m_canvas.Line(1,3, 15,3,::ColorToARGB(clr,alpha)); //--- Draw the left triangle this.m_canvas.Line(1,3, 1,3,::ColorToARGB(clr,alpha)); this.m_canvas.Line(2,2, 2,4,::ColorToARGB(clr,alpha)); this.m_canvas.Line(3,1, 3,5,::ColorToARGB(clr,alpha)); //--- Draw the right triangle this.m_canvas.Line(13,1, 13,5,::ColorToARGB(clr,alpha)); this.m_canvas.Line(14,2, 14,4,::ColorToARGB(clr,alpha)); this.m_canvas.Line(15,3, 15,3,::ColorToARGB(clr,alpha)); if(update) this.m_canvas.Update(false); return true; } //+------------------------------------------------------------------+ //| CImagePainter::Draw a vertical 7x17 double arrow | //+------------------------------------------------------------------+ bool CImagePainter::ArrowVert(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true) { //--- If the image area is not valid, return 'false' if(!this.CheckBound()) return false; //--- Shape coordinates int arrx[15]={3, 6, 6, 4, 4, 6, 6, 3, 0, 0, 2, 2, 0, 0, 3}; int arry[15]={0, 3, 4, 4, 12, 12, 13, 16, 13, 12, 12, 4, 4, 3, 0}; //--- Draw the white background this.m_canvas.Polyline(arrx,arry,::ColorToARGB(clrWhite,alpha)); //--- Draw the line of arrows this.m_canvas.Line(3,1, 3,15,::ColorToARGB(clr,alpha)); //--- Draw the top triangle this.m_canvas.Line(3,1, 3,1,::ColorToARGB(clr,alpha)); this.m_canvas.Line(2,2, 4,2,::ColorToARGB(clr,alpha)); this.m_canvas.Line(1,3, 5,3,::ColorToARGB(clr,alpha)); //--- Draw the bottom triangle this.m_canvas.Line(1,13, 5,13,::ColorToARGB(clr,alpha)); this.m_canvas.Line(2,14, 4,14,::ColorToARGB(clr,alpha)); this.m_canvas.Line(3,15, 3,15,::ColorToARGB(clr,alpha)); if(update) this.m_canvas.Update(false); return true; } //+-------------------------------------------------------------------+ //| CImagePainter::Draws a diagonal line from top-left to bottom-right| //| 13х13 double arrow (NorthWest-SouthEast) | //+-------------------------------------------------------------------+ bool CImagePainter::ArrowNWSE(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true) { //--- If the image area is not valid, return 'false' if(!this.CheckBound()) return false; //--- Shape coordinates int arrx[19]={0, 4, 5, 4, 4, 9, 10, 11, 12, 12, 8, 7, 8, 8, 3, 2, 1, 0, 0}; int arry[19]={0, 0, 1, 2, 3, 8, 8, 7, 8, 12, 12, 11, 10, 9, 4, 4, 5, 4, 0}; //--- Draw the white background this.m_canvas.Polyline(arrx,arry,::ColorToARGB(clrWhite,alpha)); //--- Draw the line of arrows this.m_canvas.Line(3,3, 9,9,::ColorToARGB(clr,alpha)); //--- Draw the top-left triangle this.m_canvas.Line(1,1, 4,1,::ColorToARGB(clr,alpha)); this.m_canvas.Line(1,2, 3,2,::ColorToARGB(clr,alpha)); this.m_canvas.Line(1,3, 3,3,::ColorToARGB(clr,alpha)); this.m_canvas.Line(1,4, 1,4,::ColorToARGB(clr,alpha)); //--- Draw the bottom-right triangle this.m_canvas.Line(11,8, 11, 8,::ColorToARGB(clr,alpha)); this.m_canvas.Line(9, 9, 11, 9,::ColorToARGB(clr,alpha)); this.m_canvas.Line(9,10, 11,10,::ColorToARGB(clr,alpha)); this.m_canvas.Line(8,11, 11,11,::ColorToARGB(clr,alpha)); if(update) this.m_canvas.Update(false); return true; } //+------------------------------------------------------------------+ //| CImagePainter::Draw a diagonal line from bottom-left to top-right| //| 13х13 double arrow (NorthEast-SouthWest) | //+------------------------------------------------------------------+ bool CImagePainter::ArrowNESW(const int x,const int y,const int w,const int h,const color clr,const uchar alpha,const bool update=true) { //--- If the image area is not valid, return 'false' if(!this.CheckBound()) return false; //--- Shape coordinates int arrx[19]={ 0, 0, 1, 2, 3, 8, 8, 7, 8, 12, 12, 11, 10, 9, 4, 4, 5, 4, 0}; int arry[19]={12, 8, 7, 8, 8, 3, 2, 1, 0, 0, 4, 5, 4, 4, 9, 10, 11, 12, 12}; //--- Draw the white background this.m_canvas.Polyline(arrx,arry,::ColorToARGB(clrWhite,alpha)); //--- Draw the line of arrows this.m_canvas.Line(3,9, 9,3,::ColorToARGB(clr,alpha)); //--- Draw the bottom-left triangle this.m_canvas.Line(1, 8, 1,8, ::ColorToARGB(clr,alpha)); this.m_canvas.Line(1, 9, 3,9, ::ColorToARGB(clr,alpha)); this.m_canvas.Line(1,10, 3,10,::ColorToARGB(clr,alpha)); this.m_canvas.Line(1,11, 4,11,::ColorToARGB(clr,alpha)); //--- Draw the top-right triangle this.m_canvas.Line(8, 1, 11,1,::ColorToARGB(clr,alpha)); this.m_canvas.Line(9, 2, 11,2,::ColorToARGB(clr,alpha)); this.m_canvas.Line(9, 3, 11,3,::ColorToARGB(clr,alpha)); this.m_canvas.Line(11,4, 11,4,::ColorToARGB(clr,alpha)); if(update) this.m_canvas.Update(false); return true; }
先在指定坐标处绘制白色底衬，然后在其上绘制双向箭头。
现在，实现提示框对象类：
//+------------------------------------------------------------------+ //| Hint class | //+------------------------------------------------------------------+ class CVisualHint : public CButton { protected: ENUM_HINT_TYPE m_hint_type; // Hint type //--- Draw (1) a tooltip, (2) a horizontal, (3) a vertical arrow, //--- arrows (4) top-left --- bottom-right, (5) bottom-left --- top-right void DrawTooltip(void); void DrawArrHorz(void); void DrawArrVert(void); void DrawArrNWSE(void); void DrawArrNESW(void); //--- Initialize colors for the hint type (1) Tooltip, (2) arrows void InitColorsTooltip(void); void InitColorsArrowed(void); public: //--- (1) Set and (2) return the hint type void SetHintType(const ENUM_HINT_TYPE type); ENUM_HINT_TYPE HintType(void) const { return this.m_hint_type; } //--- Draw the appearance virtual void Draw(const bool chart_redraw); //--- Virtual methods of (1) comparing, (2) saving to file, (3) loading from file, (4) object type virtual int Compare(const CObject *node,const int mode=0) const; virtual bool Save(const int file_handle) { return CButton::Save(file_handle); } virtual bool Load(const int file_handle) { return CButton::Load(file_handle); } virtual int Type(void) const { return(ELEMENT_TYPE_HINT); } //--- Initialize (1) the class object and (2) default object colors void Init(const string text); virtual void InitColors(void); //--- Constructors/destructor CVisualHint(void); CVisualHint(const string object_name, const long chart_id, const int wnd, const int x, const int y, const int w, const int h); ~CVisualHint (void) {} };
下面说明该类中声明的方法。
类构造函数：
//+------------------------------------------------------------------+ //| CVisualHint::Default constructor. | //| Builds an element in the main window of the current chart | //| at 0,0 coordinates with default dimensions | //+------------------------------------------------------------------+ CVisualHint::CVisualHint(void) : CButton("HintObject","",::ChartID(),0,0,0,DEF_BUTTON_W,DEF_BUTTON_H) { //--- Initialization this.Init(""); } //+------------------------------------------------------------------+ //| CVisualHint::Parametric constructor. | //| Builds an element in the specified window of the specified chart | //| with the specified text, coordinates and dimensions | //+------------------------------------------------------------------+ CVisualHint::CVisualHint(const string object_name,const long chart_id,const int wnd,const int x,const int y,const int w,const int h) : CButton(object_name,"",chart_id,wnd,x,y,w,h) { //--- Initialization this.Init(""); }
传递给构造函数的参数会被设置到父类对象中，并调用对象的初始化方法。
类对象初始化方法：
//+------------------------------------------------------------------+ //| CVisualHint::Initialization | //+------------------------------------------------------------------+ void CVisualHint::Init(const string text) { //--- Initialize the default colors this.InitColors(); //--- Set the offset and dimensions of the image area this.SetImageBound(0,0,this.Width(),this.Height()); //--- The object is not clipped to the container boundaries this.m_trim_flag=false; //--- Initialize the auto-repeat counters this.m_autorepeat_flag=true; //--- Initialize the properties of the event auto-repeat control object this.m_autorepeat.SetChartID(this.m_chart_id); this.m_autorepeat.SetID(0); this.m_autorepeat.SetName("VisualHintAutorepeatControl"); this.m_autorepeat.SetDelay(DEF_AUTOREPEAT_DELAY); this.m_autorepeat.SetInterval(DEF_AUTOREPEAT_INTERVAL); this.m_autorepeat.SetEvent(CHARTEVENT_OBJECT_CLICK,0,0,this.NameFG()); }
这里，为对象设置一个标记，禁止沿容器边界对其进行裁剪。所有提示框都保存在各个界面元素的提示框列表中。对象初始状态为隐藏，仅在光标与元素边界发生交互事件时才显示。如果启用了沿容器尺寸裁剪的标记，箭头提示框将始终处于隐藏状态，因为它们的位置通常都在元素外部。
对于提示框类型而言，它默认会沿所属容器边界被裁剪，这是不合理的，因为提示框既可以完全位于元素内部，也可以部分或完全超出元素范围。因此，同样需要为它重置沿容器边界裁剪的标记。
提示框类型的颜色初始化方法：
//+------------------------------------------------------------------+ //| CVisualHint::Initialize colors for the Tooltip hint type | //+------------------------------------------------------------------+ void CVisualHint::InitColorsTooltip(void) { //--- The background and foreground are opaque this.SetAlpha(255); //--- Initialize the background colors for the normal and activated states and make it the current background color this.InitBackColors(clrWhiteSmoke,clrWhiteSmoke,clrWhiteSmoke,clrWhiteSmoke); this.InitBackColorsAct(clrWhiteSmoke,clrWhiteSmoke,clrWhiteSmoke,clrWhiteSmoke); this.BackColorToDefault(); //--- Initialize the foreground colors for the normal and activated states and make it the current text color this.InitForeColors(clrBlack,clrBlack,clrBlack,clrSilver); this.InitForeColorsAct(clrBlack,clrBlack,clrBlack,clrSilver); this.ForeColorToDefault(); //--- Initialize the border colors for the normal and activated states and make it the current border color this.InitBorderColors(clrLightGray,clrLightGray,clrLightGray,clrLightGray); this.InitBorderColorsAct(clrLightGray,clrLightGray,clrLightGray,clrLightGray); this.BorderColorToDefault(); //--- Initialize the border color and foreground color for the disabled element this.InitBorderColorBlocked(clrNULL); this.InitForeColorBlocked(clrNULL); }
箭头型提示框颜色的初始化方法：
//+------------------------------------------------------------------+ //| CVisualHint::Initialize colors for the Arrowed tooltip type | //+------------------------------------------------------------------+ void CVisualHint::InitColorsArrowed(void) { //--- Background is transparent, foreground is opaque this.SetAlphaBG(0); this.SetAlphaFG(255); //--- Initialize the background colors for the normal and activated states and make it the current background color this.InitBackColors(clrNULL,clrNULL,clrNULL,clrNULL); this.InitBackColorsAct(clrNULL,clrNULL,clrNULL,clrNULL); this.BackColorToDefault(); //--- Initialize the foreground colors for the normal and activated states and make it the current text color this.InitForeColors(clrBlack,clrBlack,clrBlack,clrSilver); this.InitForeColorsAct(clrBlack,clrBlack,clrBlack,clrSilver); this.ForeColorToDefault(); //--- Initialize the border colors for the normal and activated states and make it the current border color this.InitBorderColors(clrNULL,clrNULL,clrNULL,clrNULL); this.InitBorderColorsAct(clrNULL,clrNULL,clrNULL,clrNULL); this.BorderColorToDefault(); //--- Initialize the border color and foreground color for the disabled element this.InitBorderColorBlocked(clrNULL); this.InitForeColorBlocked(clrNULL); }
每种提示框都有各自的背景色、前景色和边框色。默认颜色可以随时重新定义，之后提示框将使用新设置的颜色。
默认对象颜色的初始化方法：
//+------------------------------------------------------------------+ //| CVisualHint::Initialize the object default colors | //+------------------------------------------------------------------+ void CVisualHint::InitColors(void) { if(this.m_hint_type==HINT_TYPE_TOOLTIP) this.InitColorsTooltip(); else this.InitColorsArrowed(); }
针对每种提示框类型，调用对应的默认颜色初始化方法。
设置提示框类型的方法：
//+------------------------------------------------------------------+ //| CVisualHint::Set the hint type | //+------------------------------------------------------------------+ void CVisualHint::SetHintType(const ENUM_HINT_TYPE type) { //--- If the passed type matches the set one, leave if(this.m_hint_type==type) return; //--- Set a new hint type this.m_hint_type=type; //--- Depending on the hint type, set the object dimensions switch(this.m_hint_type) { case HINT_TYPE_ARROW_HORZ : this.Resize(17,7); break; case HINT_TYPE_ARROW_VERT : this.Resize(7,17); break; case HINT_TYPE_ARROW_NESW : case HINT_TYPE_ARROW_NWSE : this.Resize(13,13); break; default : break; } //--- Set the offset and dimensions of the image area, //--- initialize colors based on the hint type this.SetImageBound(0,0,this.Width(),this.Height()); this.InitColors(); }
一个对象可以有五种提示框：普通提示框以及四个双向箭头。该方法设置指定的类型，调整对象尺寸，并根据设置的提示对象初始化对象颜色。
绘制外观的方法：
//+------------------------------------------------------------------+ //| CVisualHint::Draw the appearance | //+------------------------------------------------------------------+ void CVisualHint::Draw(const bool chart_redraw) { //--- Depending on the type of hint, call the corresponding drawing method switch(this.m_hint_type) { case HINT_TYPE_ARROW_HORZ : this.DrawArrHorz(); break; case HINT_TYPE_ARROW_VERT : this.DrawArrVert(); break; case HINT_TYPE_ARROW_NESW : this.DrawArrNESW(); break; case HINT_TYPE_ARROW_NWSE : this.DrawArrNWSE(); break; default : this.DrawTooltip(); break; } //--- If specified, update the chart if(chart_redraw) ::ChartRedraw(this.m_chart_id); }
根据设置的提示框类型，调用对应的绘制方法。
不同类型提示框的绘制方法：
//+------------------------------------------------------------------+ //| CVisualHint::Draw the tooltip | //+------------------------------------------------------------------+ void CVisualHint::DrawTooltip(void) { //--- Fill the object with the background color, draw the frame and update the background canvas this.Fill(this.BackColor(),false); this.m_background.Rectangle(this.AdjX(0),this.AdjY(0),this.AdjX(this.Width()-1),this.AdjY(this.Height()-1),::ColorToARGB(this.BorderColor(),this.AlphaBG())); this.m_background.Update(false); } //+------------------------------------------------------------------+ //| CVisualHint::Draw the horizontal arrow | //+------------------------------------------------------------------+ void CVisualHint::DrawArrHorz(void) { //--- Clear the drawing area this.m_painter.Clear(this.AdjX(this.m_painter.X()),this.AdjY(this.m_painter.Y()),this.m_painter.Width(),this.m_painter.Height(),false); //--- Draw the double horizontal arrow this.m_painter.ArrowHorz(this.AdjX(this.m_painter.X()),this.AdjY(this.m_painter.Y()),this.m_painter.Width(),this.m_painter.Height(),this.ForeColor(),this.AlphaFG(),true); } //+------------------------------------------------------------------+ //| CVisualHint::Draw the vertical arrow | //+------------------------------------------------------------------+ void CVisualHint::DrawArrVert(void) { //--- Clear the drawing area this.m_painter.Clear(this.AdjX(this.m_painter.X()),this.AdjY(this.m_painter.Y()),this.m_painter.Width(),this.m_painter.Height(),false); //--- Draw the double vertical arrow this.m_painter.ArrowVert(this.AdjX(this.m_painter.X()),this.AdjY(this.m_painter.Y()),this.m_painter.Width(),this.m_painter.Height(),this.ForeColor(),this.AlphaFG(),true); } //+------------------------------------------------------------------+ //| CVisualHint::Draw arrows from top-left --- bottom-right | //+------------------------------------------------------------------+ void CVisualHint::DrawArrNWSE(void) { //--- Clear the drawing area this.m_painter.Clear(this.AdjX(this.m_painter.X()),this.AdjY(this.m_painter.Y()),this.m_painter.Width(),this.m_painter.Height(),false); //--- Draw a double diagonal arrow from top-left to bottom-right this.m_painter.ArrowNWSE(this.AdjX(this.m_painter.X()),this.AdjY(this.m_painter.Y()),this.m_painter.Width(),this.m_painter.Height(),this.ForeColor(),this.AlphaFG(),true); } //+------------------------------------------------------------------+ //| CVisualHint::Draws arrows bottom-left --- top-right | //+------------------------------------------------------------------+ void CVisualHint::DrawArrNESW(void) { //--- Clear the drawing area this.m_painter.Clear(this.AdjX(this.m_painter.X()),this.AdjY(this.m_painter.Y()),this.m_painter.Width(),this.m_painter.Height(),false); //--- Draw a double diagonal arrow from bottom-left to top-right this.m_painter.ArrowNESW(this.AdjX(this.m_painter.X()),this.AdjY(this.m_painter.Y()),this.m_painter.Width(),this.m_painter.Height(),this.ForeColor(),this.AlphaFG(),true); }
目前只完整实现了绘制箭头提示框的方法。要实现普通提示框（Tooltip类型），需要完善绘制方法，并实现一个在背景画布上显示指定文本的方法。
完善控件
在CListObj对象列表类的元素创建方法中，添加一个提示框对象：
//+------------------------------------------------------------------+ //| List element creation method | //+------------------------------------------------------------------+ CObject *CListObj::CreateElement(void) { //--- Create a new object depending on the object type in m_element_type switch(this.m_element_type) { case ELEMENT_TYPE_BASE : return new CBaseObj(); // Basic object of graphical elements case ELEMENT_TYPE_COLOR : return new CColor(); // Color object case ELEMENT_TYPE_COLORS_ELEMENT : return new CColorElement(); // Color object of the graphical object element case ELEMENT_TYPE_RECTANGLE_AREA : return new CBound(); // Rectangular area of the element case ELEMENT_TYPE_IMAGE_PAINTER : return new CImagePainter(); // Object for drawing images case ELEMENT_TYPE_CANVAS_BASE : return new CCanvasBase(); // Basic object of graphical elements case ELEMENT_TYPE_ELEMENT_BASE : return new CElementBase(); // Basic object of graphical elements case ELEMENT_TYPE_HINT : return new CVisualHint(); // Hint case ELEMENT_TYPE_LABEL : return new CLabel(); // Text label case ELEMENT_TYPE_BUTTON : return new CButton(); // Simple button case ELEMENT_TYPE_BUTTON_TRIGGERED : return new CButtonTriggered(); // Toggle button case ELEMENT_TYPE_BUTTON_ARROW_UP : return new CButtonArrowUp(); // Up arrow button case ELEMENT_TYPE_BUTTON_ARROW_DOWN : return new CButtonArrowDown(); // Down arrow button case ELEMENT_TYPE_BUTTON_ARROW_LEFT : return new CButtonArrowLeft(); // Left arrow button case ELEMENT_TYPE_BUTTON_ARROW_RIGHT: return new CButtonArrowRight(); // Right arrow button case ELEMENT_TYPE_CHECKBOX : return new CCheckBox(); // CheckBox control case ELEMENT_TYPE_RADIOBUTTON : return new CRadioButton(); // RadioButton control case ELEMENT_TYPE_PANEL : return new CPanel(); // Panel control case ELEMENT_TYPE_GROUPBOX : return new CGroupBox(); // GroupBox control case ELEMENT_TYPE_CONTAINER : return new CContainer(); // GroupBox control default : return NULL; } }
在图形元素基类中添加（声明）新的变量与方法：
//+------------------------------------------------------------------+ //| Graphical element base class | //+------------------------------------------------------------------+ class CElementBase : public CCanvasBase { protected: CImagePainter m_painter; // Drawing class CListObj m_list_hints; // List of hints int m_group; // Group of elements bool m_visible_in_container; // Visibility flag in the container //--- Add the specified hint object to the list bool AddHintToList(CVisualHint *obj); //--- Create and add a new hint object to the list CVisualHint *CreateAndAddNewHint(const ENUM_HINT_TYPE type, const string user_name, const int w, const int h); //--- Add an existing hint object to the list CVisualHint *AddHint(CVisualHint *obj, const int dx, const int dy); //--- (1) Add to the list and (2) remove tooltip objects with arrows from the list bool AddHintsArrowed(void); bool DeleteHintsArrowed(void); //--- Displays the resize cursor bool ShowCursorHint(const ENUM_CURSOR_REGION edge,int x,int y); //--- Handler for dragging element edges and corners virtual void ResizeActionDragHandler(const int x, const int y); //--- Handlers for resizing the element by sides and corners virtual bool ResizeZoneLeftHandler(const int x, const int y); virtual bool ResizeZoneRightHandler(const int x, const int y); virtual bool ResizeZoneTopHandler(const int x, const int y); virtual bool ResizeZoneBottomHandler(const int x, const int y); virtual bool ResizeZoneLeftTopHandler(const int x, const int y); virtual bool ResizeZoneRightTopHandler(const int x, const int y); virtual bool ResizeZoneLeftBottomHandler(const int x, const int y); virtual bool ResizeZoneRightBottomHandler(const int x, const int y); //--- Return the pointer to a hint by (1) index, (2) ID and (3) name CVisualHint *GetHintAt(const int index); CVisualHint *GetHint(const int id); CVisualHint *GetHint(const string name); //--- Create a new hint CVisualHint *CreateNewHint(const ENUM_HINT_TYPE type, const string object_name, const string user_name, const int id, const int x, const int y, const int w, const int h); //--- (1) Show the specified tooltip with arrows and (2) hide all tooltips void ShowHintArrowed(const ENUM_HINT_TYPE type,const int x,const int y); void HideHintsAll(const bool chart_redraw); public: //--- Return the pointer to (1) the drawing class and (2) the list of hints CImagePainter *Painter(void) { return &this.m_painter; } CListObj *GetListHints(void) { return &this.m_list_hints; } //--- Create and add (1) a new and (2) previously created hint object (tooltip only) to the list CVisualHint *InsertNewTooltip(const ENUM_HINT_TYPE type, const string user_name, const int w, const int h); CVisualHint *InsertTooltip(CVisualHint *obj, const int dx, const int dy); //--- (1) Set the coordinates and (2) change the image area size void SetImageXY(const int x,const int y) { this.m_painter.SetXY(x,y); } void SetImageSize(const int w,const int h) { this.m_painter.SetSize(w,h); } //--- Set the area coordinates and image area dimensions void SetImageBound(const int x,const int y,const int w,const int h) { this.SetImageXY(x,y); this.SetImageSize(w,h); } //--- Return the (1) X, (2) Y coordinate, (3) width, (4) height, (5) right, (6) bottom image area border int ImageX(void) const { return this.m_painter.X(); } int ImageY(void) const { return this.m_painter.Y(); } int ImageWidth(void) const { return this.m_painter.Width(); } int ImageHeight(void) const { return this.m_painter.Height(); } int ImageRight(void) const { return this.m_painter.Right(); } int ImageBottom(void) const { return this.m_painter.Bottom(); } //--- (1) Set and (2) return the group of elements virtual void SetGroup(const int group) { this.m_group=group; } int Group(void) const { return this.m_group; } //--- Set the resizing flag virtual void SetResizable(const bool flag); //--- (1) Set and (2) return the flag of visibility in the container virtual void SetVisibleInContainer(const bool flag) { this.m_visible_in_container=flag; } bool IsVisibleInContainer(void) const { return this.m_visible_in_container;} //--- Return the object description virtual string Description(void); //--- Resize handler (Resize) virtual void OnResizeZoneEvent(const int id, const long lparam, const double dparam, const string sparam); //--- Virtual methods of (1) comparing, (2) saving to file, (3) loading from file, (4) object type virtual int Compare(const CObject *node,const int mode=0) const; virtual bool Save(const int file_handle); virtual bool Load(const int file_handle); virtual int Type(void) const { return(ELEMENT_TYPE_ELEMENT_BASE);} //--- Constructors/destructor CElementBase(void) { this.m_painter.CanvasAssign(this.GetForeground()); this.m_visible_in_container=true; } CElementBase(const string object_name, const string text, const long chart_id, const int wnd, const int x, const int y, const int w, const int h); ~CElementBase(void) {} };
所有添加到该元素中的提示框对象，都将存放于m_list_hints列表中。m_visible_in_container标记用于设置元素在容器中的可见性。当该标记启用时，元素的可见性由容器的Show()和Hide()方法控制。当该标记禁用时，可见性由程序员手动控制。
例如，如果容器的滚动条处于隐藏状态（容器内容完全适配可见区域），且容器本身是隐藏的，那么在调用容器的Show()方法时，若滚动条启用了该标记，也会一并显示。这并不是我们想要的效果。因此，对于滚动条，需要禁用m_visible_in_container标记，使其仅按照容器内部逻辑显示 —— 即只有当容器内容超出可见区域、需要滚动时才显示。
在类的构造函数中，设置元素在容器内的可见性标记：
//--- Constructors/destructor CElementBase(void) { this.m_painter.CanvasAssign(this.GetForeground()); this.m_visible_in_container=true; } CElementBase(const string object_name, const string text, const long chart_id, const int wnd, const int x, const int y, const int w, const int h); ~CElementBase(void) {} }; //+----------------------------------------------------------------------------------+ //| CElementBase::Parametric constructor. Builds an element in the specified | //| window of the specified chart with the specified text, coordinates and dimensions| //+----------------------------------------------------------------------------------+ CElementBase::CElementBase(const string object_name,const string text,const long chart_id,const int wnd,const int x,const int y,const int w,const int h) : CCanvasBase(object_name,chart_id,wnd,x,y,w,h),m_group(-1) { //--- Assign the foreground canvas to the drawing object and //--- reset the coordinates and dimensions, which makes it inactive, //--- set the visibility flag of the element in the container this.m_painter.CanvasAssign(this.GetForeground()); this.m_painter.SetXY(0,0); this.m_painter.SetSize(0,0); this.m_visible_in_container=true; }
设置可调整标记大小的方法：
//+------------------------------------------------------------------+ //| CElementBase::Set the resizing flag | //+------------------------------------------------------------------+ void CElementBase::SetResizable(const bool flag) { //--- Set the flag to the parent object CCanvasBase::SetResizable(flag); //--- If the flag is passed as 'true', create four hints with arrows for the cursor, if(flag) this.AddHintsArrowed(); //--- otherwise, remove the arrow hints for the cursor else this.DeleteHintsArrowed(); }
为对象设置指定的标记值。如果传入标记为true，则为该元素创建四个箭头提示框；如果传入标记为false，则删除之前创建的箭头提示框。
返回提示框指针的方法：
//+------------------------------------------------------------------+ //| CElementBase::Return the pointer to a hint by index | //+------------------------------------------------------------------+ CVisualHint *CElementBase::GetHintAt(const int index) { return this.m_list_hints.GetNodeAtIndex(index); } //+------------------------------------------------------------------+ //| CElementBase::Return the pointer to a hint by ID | //+------------------------------------------------------------------+ CVisualHint *CElementBase::GetHint(const int id) { int total=this.m_list_hints.Total(); for(int i=0;i<total;i++) { CVisualHint *obj=this.GetHintAt(i); if(obj!=NULL && obj.ID()==id) return obj; } return NULL; } //+------------------------------------------------------------------+ //|CElementBase:: Return the pointer to a hint by name | //+------------------------------------------------------------------+ CVisualHint *CElementBase::GetHint(const string name) { int total=this.m_list_hints.Total(); for(int i=0;i<total;i++) { CVisualHint *obj=this.GetHintAt(i); if(obj!=NULL && obj.Name()==name) return obj; } return NULL; }
在列表中查找具有指定属性值的提示框对象，查找成功则返回指向该对象的指针。
将指定提示框对象添加到列表的方法：
//+------------------------------------------------------------------+ //| CElementBase::Add the specified hint object to the list | //+------------------------------------------------------------------+ bool CElementBase::AddHintToList(CVisualHint *obj) { //--- If an empty pointer is passed, report this and return 'false' if(obj==NULL) { ::PrintFormat("%s: Error. Empty element passed",__FUNCTION__); return false; } //--- Set the sorting flag for the list by ID this.m_list_hints.Sort(ELEMENT_SORT_BY_ID); //--- If such an element is not in the list, return the result of adding it to the list if(this.m_list_hints.Search(obj)==NULL) return(this.m_list_hints.Add(obj)>-1); //--- An element with this ID is already in the list - return 'false' return false; }
该方法接收一个指向待加入列表对象的指针。提示框对象在添加时会通过ID进行追踪管理，这意味着每个对象都必须具备唯一的标识。
创建新提示框对象的方法：
//+------------------------------------------------------------------+ //| CElementBase::Create a new hint | //+------------------------------------------------------------------+ CVisualHint *CElementBase::CreateNewHint(const ENUM_HINT_TYPE type,const string object_name,const string user_name,const int id, const int x,const int y,const int w,const int h) { //--- Create a new hint object CVisualHint *obj=new CVisualHint(object_name,this.m_chart_id,this.m_wnd,x,y,w,h); if(obj==NULL) { ::PrintFormat("%s: Error: Failed to create Hint object",__FUNCTION__); return NULL; } //--- Set the hint ID, name, and type obj.SetID(id); obj.SetName(user_name); obj.SetHintType(type); //--- Return the pointer to a created object return obj; }
该方法创建一个新对象，并设置其用户名、ID以及提示框类型，返回指向所创建对象的指针。
创建并添加新提示框对象至列表的方法：
//+------------------------------------------------------------------+ //| CElementBase::Create and add a new hint object to the list | //+------------------------------------------------------------------+ CVisualHint *CElementBase::CreateAndAddNewHint(const ENUM_HINT_TYPE type,const string user_name,const int w,const int h) { //--- Create a graphical object name int obj_total=this.m_list_hints.Total(); string obj_name=this.NameFG()+"_HNT"+(string)obj_total; //--- Calculate the coordinates of the object below and to the right of the lower right corner of the element int x=this.Right()+1; int y=this.Bottom()+1; //--- Create a new hint object CVisualHint *obj=this.CreateNewHint(type,obj_name,user_name,obj_total,x,y,w,h); //--- If a new object is not created, return NULL if(obj==NULL) return NULL; //--- Set the image bounds, container, and z-order obj.SetImageBound(0,0,this.Width(),this.Height()); obj.SetContainerObj(&this); obj.ObjectSetZOrder(this.ObjectZOrder()+1); //--- If the created element is not added to the list, report this, remove the created element and return NULL if(!this.AddHintToList(obj)) { ::PrintFormat("%s: Error. Failed to add Hint object with ID %d to list",__FUNCTION__,obj.ID()); delete obj; return NULL; } //--- Return a pointer to the created and attached object return obj; }
该主要方法用于创建提示框并将其加入元素提示列表。
将已存在的提示框对象添加到列表的方法：
//+------------------------------------------------------------------+ //| CElementBase::Add the existing hint object to the list | //+------------------------------------------------------------------+ CVisualHint *CElementBase::AddHint(CVisualHint *obj,const int dx,const int dy) { //--- If the passed object is not of the hint type, return NULL if(obj.Type()!=ELEMENT_TYPE_HINT) { ::PrintFormat("%s: Error. Only an object with the Hint type can be used here. The element type \"%s\" was passed",__FUNCTION__,ElementDescription((ENUM_ELEMENT_TYPE)obj.Type())); return NULL; } //--- Save the object ID and set a new one int id=obj.ID(); obj.SetID(this.m_list_hints.Total()); //--- Add an object to the list; if adding fails, report it, set the initial ID, and return NULL if(!this.AddHintToList(obj)) { ::PrintFormat("%s: Error. Failed to add Hint object to list",__FUNCTION__); obj.SetID(id); return NULL; } //--- Set new coordinates, container, and z-order of the object int x=this.X()+dx; int y=this.Y()+dy; obj.Move(x,y); obj.SetContainerObj(&this); obj.ObjectSetZOrder(this.ObjectZOrder()+1); //--- Return the pointer to the attached object return obj; }
该方法将已创建好的提示框对象添加到元素的提示列表中。
将箭头提示对象添加到列表的方法：
//+------------------------------------------------------------------+ //| CElementBase::Add hint objects with arrows to the list | //+------------------------------------------------------------------+ bool CElementBase::AddHintsArrowed(void) { //--- Arrays of names and hint types string array[4]={"HintHORZ","HintVERT","HintNWSE","HintNESW"}; ENUM_HINT_TYPE type[4]={HINT_TYPE_ARROW_HORZ,HINT_TYPE_ARROW_VERT,HINT_TYPE_ARROW_NWSE,HINT_TYPE_ARROW_NESW}; //--- In the loop, create four hints with arrows bool res=true; for(int i=0;i<(int)array.Size();i++) res &=(this.CreateAndAddNewHint(type[i],array[i],0,0)!=NULL); //--- If there were errors during creation, return 'false' if(!res) return false; //--- In the loop through the array of names of hint objects for(int i=0;i<(int)array.Size();i++) { //--- get the next object by name, CVisualHint *obj=this.GetHint(array[i]); if(obj==NULL) continue; //--- hide the object and draw the appearance (arrows according to the object type) obj.Hide(false); obj.Draw(false); } //--- All is successful return true; }
该方法依次创建四种类型的箭头提示框，并将它们添加到元素的提示框列表中。
从列表中移除所有箭头提示框对象的方法：
//+------------------------------------------------------------------+ //| CElementBase::Remove tooltip objects with arrows from the list | //+------------------------------------------------------------------+ bool CElementBase::DeleteHintsArrowed(void) { //--- In the loop through the list of hint objects bool res=true; for(int i=this.m_list_hints.Total()-1;i>=0;i--) { //--- get the next object and, if it is not a tooltip, delete it CVisualHint *obj=this.m_list_hints.GetNodeAtIndex(i); if(obj!=NULL && obj.HintType()!=HINT_TYPE_TOOLTIP) res &=this.m_list_hints.DeleteCurrent(); } //--- Return the result of removing the hints with arrows return res; }
在循环中遍历提示框列表，查找类型非普通提示框的对象，并将其逐一从列表中删除。
创建并添加普通提示框类型的新提示框对象到列表中的方法：
//+------------------------------------------------------------------+ //| CElementBase::Create and add a new hint object to the list | //+------------------------------------------------------------------+ CVisualHint *CElementBase::InsertNewTooltip(const ENUM_HINT_TYPE type,const string user_name,const int w,const int h) { //--- If the hint type is not a tooltip, report this and return NULL if(type!=HINT_TYPE_TOOLTIP) { ::PrintFormat("%s: Error. Only a tooltip can be added to an element",__FUNCTION__); return NULL; } //--- Create and add a new hint object to the list; //--- Return a pointer to the created and attached object return this.CreateAndAddNewHint(type,user_name,w,h); }
将已创建好的提示框对象添加到列表中的方法：
//+------------------------------------------------------------------+ //| CElementBase::Add a previously created hint object to the list | //+------------------------------------------------------------------+ CVisualHint *CElementBase::InsertTooltip(CVisualHint *obj,const int dx,const int dy) { //--- If empty or invalid pointer to the object is passed, return NULL if(::CheckPointer(obj)==POINTER_INVALID) { ::PrintFormat("%s: Error. Empty element passed",__FUNCTION__); return NULL; } //--- If the hint type is not a tooltip, report this and return NULL if(obj.HintType()!=HINT_TYPE_TOOLTIP) { ::PrintFormat("%s: Error. Only a tooltip can be added to an element",__FUNCTION__); return NULL; } //--- Add the specified hint object to the list; //--- Return a pointer to the created and attached object return this.AddHint(obj,dx,dy); }
这些方法支持将新提示框或已存在的提示框添加到元素的提示列表中。当元素需要在鼠标悬停时，动态显示对应区域的提示内容，该功能会非常实用。
在指定坐标显示目标提示框的方法：
//+------------------------------------------------------------------+ //| CElementBase::Display the specified hint | //| at the specified coordinates | //+------------------------------------------------------------------+ void CElementBase::ShowHintArrowed(const ENUM_HINT_TYPE type,const int x,const int y) { CVisualHint *hint=NULL; // Pointer to the object being searched for //--- In a loop through the list of hint objects for(int i=0;i<this.m_list_hints.Total();i++) { //--- get the pointer to the next object CVisualHint *obj=this.GetHintAt(i); if(obj==NULL) continue; //--- If this is the required hint type, save the pointer, if(obj.HintType()==type) hint=obj; //--- otherwise - hide the object else obj.Hide(false); } //--- If the desired object is found and it is hidden if(hint!=NULL && hint.IsHidden()) { //--- place the object at the specified coordinates, //--- draw the appearance and bring the object to the front, making it visible hint.Move(x,y); hint.Draw(false); hint.BringToTop(true); } }
该方法会查找指定类型的提示框，并在方法形参指定的坐标位置显示它。它会显示第一个匹配该类型的提示框，其余所有提示框均隐藏。此方法专门用于显示箭头提示框，列表中应存在四个此类对象。执行时会先在循环中隐藏所有提示框，再显示目标提示框。
隐藏所有提示框的方法：
//+------------------------------------------------------------------+ //| CElementBase::Hide all hints | //+------------------------------------------------------------------+ void CElementBase::HideHintsAll(const bool chart_redraw) { //--- In the loop through the list of hint objects for(int i=0;i<this.m_list_hints.Total();i++) { //--- get the next object and hide it CVisualHint *obj=this.GetHintAt(i); if(obj!=NULL) obj.Hide(false); } //--- If specified, redraw the chart if(chart_redraw) ::ChartRedraw(this.m_chart_id); }
在遍历提示框对象列表的循环中，将列表中的每个常规对象均设为隐藏。
在光标旁显示提示框的方法：
//+------------------------------------------------------------------+ //| CElementBase::Displays the resize cursor | //+------------------------------------------------------------------+ bool CElementBase::ShowCursorHint(const ENUM_CURSOR_REGION edge,int x,int y) { CVisualHint *hint=NULL; // Pointer to the hint int hint_shift_x=0; // Hint offset by X int hint_shift_y=0; // Hint offset by Y //--- Depending on the location of the cursor on the element borders //--- specify the tooltip offsets relative to the cursor coordinates, //--- display the required hint on the chart and get the pointer to this object switch(edge) { //--- Cursor on the right or left border - horizontal double arrow case CURSOR_REGION_RIGHT : case CURSOR_REGION_LEFT : hint_shift_x=1; hint_shift_y=18; this.ShowHintArrowed(HINT_TYPE_ARROW_HORZ,x+hint_shift_x,y+hint_shift_y); hint=this.GetHint("HintHORZ"); break; //--- Cursor at the top or bottom border - vertical double arrow case CURSOR_REGION_TOP : case CURSOR_REGION_BOTTOM : hint_shift_x=12; hint_shift_y=4; this.ShowHintArrowed(HINT_TYPE_ARROW_VERT,x+hint_shift_x,y+hint_shift_y); hint=this.GetHint("HintVERT"); break; //--- Cursor in the upper left or lower right corner - a diagonal double arrow from top left to bottom right case CURSOR_REGION_LEFT_TOP : case CURSOR_REGION_RIGHT_BOTTOM : hint_shift_x=10; hint_shift_y=2; this.ShowHintArrowed(HINT_TYPE_ARROW_NWSE,x+hint_shift_x,y+hint_shift_y); hint=this.GetHint("HintNWSE"); break; //--- Cursor in the lower left or upper right corner - a diagonal double arrow from bottom left to top right case CURSOR_REGION_LEFT_BOTTOM : case CURSOR_REGION_RIGHT_TOP : hint_shift_x=5; hint_shift_y=12; this.ShowHintArrowed(HINT_TYPE_ARROW_NESW,x+hint_shift_x,y+hint_shift_y); hint=this.GetHint("HintNESW"); break; //--- By default, do nothing default: break; } //--- Return the result of adjusting the position of the tooltip relative to the cursor return(hint!=NULL ? hint.Move(x+hint_shift_x,y+hint_shift_y) : false); }
根据元素的边缘或角点位置，在光标旁显示对应的提示框。
尺寸调整事件处理函数：
//+------------------------------------------------------------------+ //| CElementBase::Resize handler | //+------------------------------------------------------------------+ void CElementBase::OnResizeZoneEvent(const int id,const long lparam,const double dparam,const string sparam) { int x=(int)lparam; // Cursor X coordinate int y=(int)dparam; // Cursor Y coordinate int shift_x=0; // Offset by X int shift_y=0; // Offset by Y //--- Get the cursor position relative to the element borders and the interaction mode ENUM_CURSOR_REGION edge=(this.ResizeRegion()==CURSOR_REGION_NONE ? this.CheckResizeZone(x,y) : this.ResizeRegion()); ENUM_RESIZE_ZONE_ACTION action=(ENUM_RESIZE_ZONE_ACTION)id; //--- If the cursor is outside the resizing boundaries or has just hovered over the interaction zone if(action==RESIZE_ZONE_ACTION_NONE || (action==RESIZE_ZONE_ACTION_HOVER && edge==CURSOR_REGION_NONE)) { //--- disable the resizing mode and the interaction region, //--- hide all hints this.SetResizeMode(false); this.SetResizeRegion(CURSOR_REGION_NONE); this.HideHintsAll(true); } //--- The cursor is on one of the resizing boundaries if(action==RESIZE_ZONE_ACTION_HOVER) { //--- Display a hint with the arrow for the interaction region if(this.ShowCursorHint(edge,x,y)) ::ChartRedraw(this.m_chart_id); } //--- Start resizing if(action==RESIZE_ZONE_ACTION_BEGIN) { //--- enable the resizing mode and the interaction region, //--- display the corresponding cursor hint this.SetResizeMode(true); this.SetResizeRegion(edge); this.ShowCursorHint(edge,x,y); } //--- Drag the border of an object to resize the element if(action==RESIZE_ZONE_ACTION_DRAG) { //--- Call the handler for dragging the object borders to resize, //--- display the corresponding cursor hint this.ResizeActionDragHandler(x,y); this.ShowCursorHint(edge,x,y); } }
作为事件标识（id），交互区域内的光标操作会被传入处理函数（指向区域、按住鼠标拖动、松开鼠标）。接下来，我们获取事件发生的元素边界并进行处理。整套逻辑已在代码注释中详细说明，希望不会产生疑问。所有场景均由专用处理函数实现，下文会逐一介绍。
元素边缘与角点拖动处理函数：
//+------------------------------------------------------------------+ //| CElementBase::Handler for dragging element edges and corners | //+------------------------------------------------------------------+ void CElementBase::ResizeActionDragHandler(const int x, const int y) { //--- Resize beyond the right border if(this.ResizeRegion()==CURSOR_REGION_RIGHT) this.ResizeZoneRightHandler(x,y); //--- Resize beyond the bottom border if(this.ResizeRegion()==CURSOR_REGION_BOTTOM) this.ResizeZoneBottomHandler(x,y); //--- Resize beyond the left border if(this.ResizeRegion()==CURSOR_REGION_LEFT) this.ResizeZoneLeftHandler(x,y); //--- Resize beyond the upper border if(this.ResizeRegion()==CURSOR_REGION_TOP) this.ResizeZoneTopHandler(x,y); //--- Resize by the lower right corner if(this.ResizeRegion()==CURSOR_REGION_RIGHT_BOTTOM) this.ResizeZoneRightBottomHandler(x,y); //--- Resize by the upper right corner if(this.ResizeRegion()==CURSOR_REGION_RIGHT_TOP) this.ResizeZoneRightTopHandler(x,y); //--- Resize by the lower left corner if(this.ResizeRegion()==CURSOR_REGION_LEFT_BOTTOM) this.ResizeZoneLeftBottomHandler(x,y); //--- Resize by the upper left corner if(this.ResizeRegion()==CURSOR_REGION_LEFT_TOP) this.ResizeZoneLeftTopHandler(x,y); }
根据交互发生的元素边缘或角点位置，调用对应的专用事件处理函数。
//+------------------------------------------------------------------+ //| CElementBase::Bottom edge resize handler | //+------------------------------------------------------------------+ bool CElementBase::ResizeZoneBottomHandler(const int x,const int y) { //--- Calculate and set the new element height int height=::fmax(y-this.Y(),DEF_PANEL_MIN_H); if(!this.ResizeH(height)) return false; //--- Get the pointer to the hint CVisualHint *hint=this.GetHint("HintVERT"); if(hint==NULL) return false; //--- Shift the hint by the specified values relative to the cursor int shift_x=12; int shift_y=4; return hint.Move(x+shift_x,y+shift_y); } //+------------------------------------------------------------------+ //| CElementBase::Resize beyond the left border | //+------------------------------------------------------------------+ bool CElementBase::ResizeZoneLeftHandler(const int x,const int y) { //--- Calculate the new X coordinate and element width int new_x=::fmin(x,this.Right()-DEF_PANEL_MIN_W+1); int width=this.Right()-new_x+1; //--- Set the new X coordinate and element width if(!this.MoveXYWidthResize(new_x,this.Y(),width,this.Height())) return false; //--- Get the pointer to the hint CVisualHint *hint=this.GetHint("HintHORZ"); if(hint==NULL) return false; //--- Shift the hint by the specified values relative to the cursor int shift_x=1; int shift_y=18; return hint.Move(x+shift_x,y+shift_y); } //+------------------------------------------------------------------+ //| CElementBase::Resize beyond the upper border | //+------------------------------------------------------------------+ bool CElementBase::ResizeZoneTopHandler(const int x,const int y) { //--- Calculate the new Y coordinate and element height int new_y=::fmin(y,this.Bottom()-DEF_PANEL_MIN_H+1); int height=this.Bottom()-new_y+1; //--- Set the new Y coordinate and element height if(!this.MoveXYWidthResize(this.X(),new_y,this.Width(),height)) return false; //--- Get the pointer to the hint CVisualHint *hint=this.GetHint("HintVERT"); if(hint==NULL) return false; //--- Shift the hint by the specified values relative to the cursor int shift_x=12; int shift_y=4; return hint.Move(x+shift_x,y+shift_y); } //+------------------------------------------------------------------+ //| CElementBase::Resize by the lower right corner | //+------------------------------------------------------------------+ bool CElementBase::ResizeZoneRightBottomHandler(const int x,const int y) { //--- Calculate and set the new element width and height int width =::fmax(x-this.X()+1, DEF_PANEL_MIN_W); int height=::fmax(y-this.Y()+1, DEF_PANEL_MIN_H); if(!this.Resize(width,height)) return false; //--- Get the pointer to the hint CVisualHint *hint=this.GetHint("HintNWSE"); if(hint==NULL) return false; //--- Shift the hint by the specified values relative to the cursor int shift_x=10; int shift_y=2; return hint.Move(x+shift_x,y+shift_y); } //+------------------------------------------------------------------+ //| CElementBase::Resize by the upper right corner | //+------------------------------------------------------------------+ bool CElementBase::ResizeZoneRightTopHandler(const int x,const int y) { //--- Calculate and set the new X coordinate, element width and height int new_y=::fmin(y, this.Bottom()-DEF_PANEL_MIN_H+1); int width =::fmax(x-this.X()+1, DEF_PANEL_MIN_W); int height=this.Bottom()-new_y+1; if(!this.MoveXYWidthResize(this.X(),new_y,width,height)) return false; //--- Get the pointer to the hint CVisualHint *hint=this.GetHint("HintNESW"); if(hint==NULL) return false; //--- Shift the hint by the specified values relative to the cursor int shift_x=5; int shift_y=12; return hint.Move(x+shift_x,y+shift_y); } //+------------------------------------------------------------------+ //| CElementBase::Resize by the lower left corner | //+------------------------------------------------------------------+ bool CElementBase::ResizeZoneLeftBottomHandler(const int x,const int y) { //--- Calculate and set the new Y coordinate, element width and height int new_x=::fmin(x, this.Right()-DEF_PANEL_MIN_W+1); int width =this.Right()-new_x+1; int height=::fmax(y-this.Y()+1, DEF_PANEL_MIN_H); if(!this.MoveXYWidthResize(new_x,this.Y(),width,height)) return false; //--- Get the pointer to the hint CVisualHint *hint=this.GetHint("HintNESW"); if(hint==NULL) return false; //--- Shift the hint by the specified values relative to the cursor int shift_x=5; int shift_y=12; return hint.Move(x+shift_x,y+shift_y); } //+------------------------------------------------------------------+ //| CElementBase::Resize by the upper left corner | //+------------------------------------------------------------------+ bool CElementBase::ResizeZoneLeftTopHandler(const int x,const int y) { //--- Calculate and set the new X and Y coordinates, element width and height int new_x=::fmin(x,this.Right()-DEF_PANEL_MIN_W+1); int new_y=::fmin(y,this.Bottom()-DEF_PANEL_MIN_H+1); int width =this.Right() -new_x+1; int height=this.Bottom()-new_y+1; if(!this.MoveXYWidthResize(new_x, new_y,width,height)) return false; //--- Get the pointer to the hint CVisualHint *hint=this.GetHint("HintNWSE"); if(hint==NULL) return false; //--- Shift the hint by the specified values relative to the cursor int shift_x=10; int shift_y=2; return hint.Move(x+shift_x,y+shift_y); }
处理函数会计算元素的新尺寸，并在需要时计算其新坐标。随后设置新的尺寸（与坐标），并在光标附近显示带箭头的提示框。
在文件操作相关方法中，添加提示框列表的保存与加载功能，以及容器内的可见性标记：
//+------------------------------------------------------------------+ //| CElementBase::Save to file | //+------------------------------------------------------------------+ bool CElementBase::Save(const int file_handle) { //--- Save the parent object data if(!CCanvasBase::Save(file_handle)) return false; //--- Save the list of hints if(!this.m_list_hints.Save(file_handle)) return false; //--- Save the image object if(!this.m_painter.Save(file_handle)) return false; //--- Save the group if(::FileWriteInteger(file_handle,this.m_group,INT_VALUE)!=INT_VALUE) return false; //--- Save the visibility flag in the container if(::FileWriteInteger(file_handle,this.m_visible_in_container,INT_VALUE)!=INT_VALUE) return false; //--- All is successful return true; } //+------------------------------------------------------------------+ //| CElementBase::Load from file | //+------------------------------------------------------------------+ bool CElementBase::Load(const int file_handle) { //--- Load parent object data if(!CCanvasBase::Load(file_handle)) return false; //--- Load the list of hints if(!this.m_list_hints.Load(file_handle)) return false; //--- Load the image object if(!this.m_painter.Load(file_handle)) return false; //--- Load the group this.m_group=::FileReadInteger(file_handle,INT_VALUE); //--- Load the visibility flag in the container this.m_visible_in_container=::FileReadInteger(file_handle,INT_VALUE); //--- All is successful return true; }
容器（面板、元素组、容器）必须具备各自的尺寸调整方法。
只需在CPanel 类中实现这些虚方法，并添加一个同时修改元素尺寸与坐标的方法即可。
//+------------------------------------------------------------------+ //| Panel class | //+------------------------------------------------------------------+ class CPanel : public CLabel { private: CElementBase m_temp_elm; // Temporary object for element searching CBound m_temp_bound; // Temporary object for area searching protected: CListObj m_list_elm; // List of attached elements CListObj m_list_bounds; // List of areas //--- Add a new element to the list bool AddNewElement(CElementBase *element); public: //--- Return the pointer to the list of (1) attached elements and (2) areas CListObj *GetListAttachedElements(void) { return &this.m_list_elm; } CListObj *GetListBounds(void) { return &this.m_list_bounds; } //--- Return the attached element by (1) index in the list, (2) ID and (3) specified object name CElementBase *GetAttachedElementAt(const uint index) { return this.m_list_elm.GetNodeAtIndex(index); } CElementBase *GetAttachedElementByID(const int id); CElementBase *GetAttachedElementByName(const string name); //--- Return the area by (1) index in the list, (2) ID and (3) specified area name CBound *GetBoundAt(const uint index) { return this.m_list_bounds.GetNodeAtIndex(index); } CBound *GetBoundByID(const int id); CBound *GetBoundByName(const string name); //--- Create and add (1) a new and (2) a previously created element to the list virtual CElementBase *InsertNewElement(const ENUM_ELEMENT_TYPE type,const string text,const string user_name,const int dx,const int dy,const int w,const int h); virtual CElementBase *InsertElement(CElementBase *element,const int dx,const int dy); //--- Create and add a new area to the list CBound *InsertNewBound(const string name,const int dx,const int dy,const int w,const int h); //--- Resize the object virtual bool ResizeW(const int w); virtual bool ResizeH(const int h); virtual bool Resize(const int w,const int h); //--- Draw the appearance virtual void Draw(const bool chart_redraw); //--- Virtual methods of (1) comparing, (2) saving to file, (3) loading from file, (4) object type virtual int Compare(const CObject *node,const int mode=0) const; virtual bool Save(const int file_handle); virtual bool Load(const int file_handle); virtual int Type(void) const { return(ELEMENT_TYPE_PANEL); } //--- Initialize (1) the class object and (2) default object colors void Init(void); virtual void InitColors(void); //--- Set new XY object coordinates virtual bool Move(const int x,const int y); //--- Shift the object by XY axes by the specified offset virtual bool Shift(const int dx,const int dy); //--- Set both the element coordinates and dimensions virtual bool MoveXYWidthResize(const int x,const int y,const int w,const int h); //--- (1) Hide and (2) display the object on all chart periods, //--- (3) bring the object to the front, (4) block, (5) unblock the element, virtual void Hide(const bool chart_redraw); virtual void Show(const bool chart_redraw); virtual void BringToTop(const bool chart_redraw); virtual void Block(const bool chart_redraw); virtual void Unblock(const bool chart_redraw); //--- Display the object description in the journal virtual void Print(void); //--- Print a list of (1) attached objects and (2) areas void PrintAttached(const uint tab=3); void PrintBounds(void); //--- Event handler virtual void OnChartEvent(const int id,const long& lparam,const double& dparam,const string& sparam); //--- Timer event handler virtual void TimerEventHandler(void); //--- Constructors/destructor CPanel(void); CPanel(const string object_name, const string text, const long chart_id, const int wnd, const int x, const int y, const int w, const int h); ~CPanel (void) { this.m_list_elm.Clear(); this.m_list_bounds.Clear(); } };
在类体外编写面板尺寸调整方法的实现代码。
//+------------------------------------------------------------------+ //| CPanel::Change the object width | //+------------------------------------------------------------------+ bool CPanel::ResizeW(const int w) { if(!this.ObjectResizeW(w)) return false; this.BoundResizeW(w); this.SetImageSize(w,this.Height()); if(!this.ObjectTrim()) { this.Update(false); this.Draw(false); } return true; } //+------------------------------------------------------------------+ //| CPanel::Change the object height | //+------------------------------------------------------------------+ bool CPanel::ResizeH(const int h) { if(!this.ObjectResizeH(h)) return false; this.BoundResizeH(h); this.SetImageSize(this.Width(),h); if(!this.ObjectTrim()) { this.Update(false); this.Draw(false); } return true; } //+------------------------------------------------------------------+ //| CPanel::Change the object size | //+------------------------------------------------------------------+ bool CPanel::Resize(const int w,const int h) { if(!this.ObjectResize(w,h)) return false; this.BoundResize(w,h); this.SetImageSize(w,h); if(!this.ObjectTrim()) { this.Update(false); this.Draw(false); } return true; }
首先，修改图形对象的尺寸，然后设置元素的新尺寸与绘图区域。接下来，按照容器边界对元素进行裁剪。
在绘制外观的方法中，应跳过滚动条，因为由其他方法负责渲染它们。
//+------------------------------------------------------------------+ //| CPanel::Draw the appearance | //+------------------------------------------------------------------+ void CPanel::Draw(const bool chart_redraw) { //--- Fill the object with background color this.Fill(this.BackColor(),false); //--- Clear the drawing area this.m_painter.Clear(this.AdjX(this.m_painter.X()),this.AdjY(this.m_painter.Y()),this.m_painter.Width(),this.m_painter.Height(),false); //--- Set the color for the dark and light lines and draw the panel frame color clr_dark =(this.BackColor()==clrNULL ? this.BackColor() : this.GetBackColorControl().NewColor(this.BackColor(),-20,-20,-20)); color clr_light=(this.BackColor()==clrNULL ? this.BackColor() : this.GetBackColorControl().NewColor(this.BackColor(), 6, 6, 6)); this.m_painter.FrameGroupElements(this.AdjX(this.m_painter.X()),this.AdjY(this.m_painter.Y()), this.m_painter.Width(),this.m_painter.Height(),this.Text(), this.ForeColor(),clr_dark,clr_light,this.AlphaFG(),true); //--- Update the background canvas without redrawing the chart this.m_background.Update(false); //--- Draw the list elements for(int i=0;i<this.m_list_elm.Total();i++) { CElementBase *elm=this.GetAttachedElementAt(i); if(elm!=NULL && elm.Type()!=ELEMENT_TYPE_SCROLLBAR_H && elm.Type()!=ELEMENT_TYPE_SCROLLBAR_V) elm.Draw(false); } //--- If specified, update the chart if(chart_redraw) ::ChartRedraw(this.m_chart_id); }
同时设置面板坐标与尺寸的方法：
//+------------------------------------------------------------------+ //| CPanel::Set both the element coordinates and dimensions | //+------------------------------------------------------------------+ bool CPanel::MoveXYWidthResize(const int x,const int y,const int w,const int h) { //--- Calculate the element movement distance int delta_x=x-this.X(); int delta_y=y-this.Y(); //--- Move the element to the specified coordinates with a resize if(!CCanvasBase::MoveXYWidthResize(x,y,w,h)) return false; this.BoundMove(x,y); this.BoundResize(w,h); this.SetImageBound(0,0,this.Width(),this.Height()); if(!this.ObjectTrim()) { this.Update(false); this.Draw(false); } //--- Move all bound elements by the calculated distance bool res=true; int total=this.m_list_elm.Total(); for(int i=0;i<total;i++) { //--- Move the bound element taking into account the offset of the parent element CElementBase *elm=this.GetAttachedElementAt(i); if(elm!=NULL) res &=elm.Move(elm.X()+delta_x,elm.Y()+delta_y); } //--- Return the result of moving all bound elements return res; }
首先，对图形对象进行位置偏移并同步修改尺寸。随后设置面板的新坐标与尺寸、更新绘图区域大小，并按容器边界裁剪元素。再将所有锚定元素按面板的偏移量同步移动。
在用于在图表所有周期上显示对象的方法中，需要排除滚动条以及带有特殊可见性标记的对象的显示。由容器对象类的相关方法控制它们的可见性。
//+------------------------------------------------------------------+ //| CPanel::Display the object on all chart periods | //+------------------------------------------------------------------+ void CPanel::Show(const bool chart_redraw) { //--- If the object is already visible, or it should not be displayed in the container, leave if(!this.m_hidden || !this.m_visible_in_container) return; //--- Display the panel CCanvasBase::Show(false); //--- Display attached objects for(int i=0;i<this.m_list_elm.Total();i++) { CElementBase *elm=this.GetAttachedElementAt(i); if(elm!=NULL) { if(elm.Type()==ELEMENT_TYPE_SCROLLBAR_H || elm.Type()==ELEMENT_TYPE_SCROLLBAR_V) continue; elm.Show(false); } } //--- If specified, redraw the chart if(chart_redraw) ::ChartRedraw(this.m_chart_id); }
同理，在将对象置于前景的方法中，必须跳过滚动条：
//+------------------------------------------------------------------+ //| CPanel::Bring an object to the foreground | //+------------------------------------------------------------------+ void CPanel::BringToTop(const bool chart_redraw) { //--- Bring the panel to the foreground CCanvasBase::BringToTop(false); //--- Bring attached objects to the foreground for(int i=0;i<this.m_list_elm.Total();i++) { CElementBase *elm=this.GetAttachedElementAt(i); if(elm!=NULL) { if(elm.Type()==ELEMENT_TYPE_SCROLLBAR_H || elm.Type()==ELEMENT_TYPE_SCROLLBAR_V) continue; elm.BringToTop(false); } } //--- If specified, redraw the chart if(chart_redraw) ::ChartRedraw(this.m_chart_id); }
滚动条自身必须设置一个标记，禁止其沿容器边界被裁剪。如果不这样做，它们的可见性将由ObjectTrim()方法控制，该方法会隐藏所有超出容器可视区域边界的对象。而滚动条恰好就位于此区域内。
在两个滚动条对象的Init方法中，设置如下标记：
//+------------------------------------------------------------------+ //| CScrollBarThumbH::Initialization | //+------------------------------------------------------------------+ void CScrollBarThumbH::Init(const string text) { //--- Initialize a parent class CButton::Init(""); //--- Set the chart relocation and update flags this.SetMovable(true); this.SetChartRedrawFlag(false); //--- The element is not clipped by the container borders this.m_trim_flag=false; //+------------------------------------------------------------------+ //| CScrollBarThumbV::Initialization | //+------------------------------------------------------------------+ void CScrollBarThumbV::Init(const string text) { //--- Initialize a parent class CButton::Init(""); //--- Set the chart relocation and update flags this.SetMovable(true); this.SetChartRedrawFlag(false); //--- The element is not clipped by the container borders this.m_trim_flag=false; }
为水平滚动条类添加两个方法 —— 设置滑块位置以及设置容器内可见性标记：
//+------------------------------------------------------------------+ //| Horizontal scrollbar class | //+------------------------------------------------------------------+ class CScrollBarH : public CPanel { protected: CButtonArrowLeft *m_butt_left; // Left arrow button CButtonArrowRight*m_butt_right; // Right arrow button CScrollBarThumbH *m_thumb; // Scrollbar slider public: //--- Return the pointer to the (1) left, (2) right button and (3) slider CButtonArrowLeft *GetButtonLeft(void) { return this.m_butt_left; } CButtonArrowRight*GetButtonRight(void) { return this.m_butt_right; } CScrollBarThumbH *GetThumb(void) { return this.m_thumb; } //--- (1) Sets and (2) return the chart update flag void SetChartRedrawFlag(const bool flag) { if(this.m_thumb!=NULL) this.m_thumb.SetChartRedrawFlag(flag); } bool ChartRedrawFlag(void) const { return(this.m_thumb!=NULL ? this.m_thumb.ChartRedrawFlag() : false); } //--- Return (1) the track length (2) start and (3) the slider position int TrackLength(void) const; int TrackBegin(void) const; int ThumbPosition(void) const; //--- Set the slider position bool SetThumbPosition(const int pos) const { return(this.m_thumb!=NULL ? this.m_thumb.MoveX(pos) : false); } //--- Change the slider size bool SetThumbSize(const uint size) const { return(this.m_thumb!=NULL ? this.m_thumb.ResizeW(size) : false); } //--- Change the object width virtual bool ResizeW(const int size); //--- Set the flag of visibility in the container virtual void SetVisibleInContainer(const bool flag); //--- Draw the appearance virtual void Draw(const bool chart_redraw); //--- Object type virtual int Type(void) const { return(ELEMENT_TYPE_SCROLLBAR_H); } //--- Initialize (1) the class object and (2) default object colors void Init(void); virtual void InitColors(void); //--- Wheel scroll handler (Wheel) virtual void OnWheelEvent(const int id, const long lparam, const double dparam, const string sparam); //--- Constructors/destructor CScrollBarH(void); CScrollBarH(const string object_name, const string text, const long chart_id, const int wnd, const int x, const int y, const int w, const int h); ~CScrollBarH(void) {} };
在类体外实现设置容器内可见性标记的方法：
//+------------------------------------------------------------------+ //| CScrollBarH::Set the flag of visibility in the container | //+------------------------------------------------------------------+ void CScrollBarH::SetVisibleInContainer(const bool flag) { this.m_visible_in_container=flag; if(this.m_butt_left!=NULL) this.m_butt_left.SetVisibleInContainer(flag); if(this.m_butt_right!=NULL) this.m_butt_right.SetVisibleInContainer(flag); if(this.m_thumb!=NULL) this.m_thumb.SetVisibleInContainer(flag); }
这里，为滚动条的每个组件设置传入该方法的标记位。
在初始化方法中，为滚动条的每个组件设置标记：
//+------------------------------------------------------------------+ //| CScrollBarH::Initialization | //+------------------------------------------------------------------+ void CScrollBarH::Init(void) { //--- Initialize a parent class CPanel::Init(); //--- background - opaque this.SetAlphaBG(255); //--- Frame width and text this.SetBorderWidth(0); this.SetText(""); //--- The element is not clipped by the container borders this.m_trim_flag=false; //--- Create scroll buttons int w=this.Height(); int h=this.Height(); this.m_butt_left = this.InsertNewElement(ELEMENT_TYPE_BUTTON_ARROW_LEFT, "","ButtL",0,0,w,h); this.m_butt_right= this.InsertNewElement(ELEMENT_TYPE_BUTTON_ARROW_RIGHT,"","ButtR",this.Width()-w,0,w,h); if(this.m_butt_left==NULL || this.m_butt_right==NULL) { ::PrintFormat("%s: Init failed",__FUNCTION__); return; } //--- Customize the colors and appearance of the left arrow button this.m_butt_left.SetImageBound(1,1,w-2,h-4); this.m_butt_left.InitBackColors(this.m_butt_left.BackColorFocused()); this.m_butt_left.ColorsToDefault(); this.m_butt_left.InitBorderColors(this.BorderColor(),this.m_butt_left.BackColorFocused(),this.m_butt_left.BackColorPressed(),this.m_butt_left.BackColorBlocked()); this.m_butt_left.ColorsToDefault(); this.m_butt_left.SetTrimmered(false); this.m_butt_left.SetVisibleInContainer(false); //--- Customize the colors and appearance of the right arrow button this.m_butt_right.SetImageBound(1,1,w-2,h-4); this.m_butt_right.InitBackColors(this.m_butt_right.BackColorFocused()); this.m_butt_right.ColorsToDefault(); this.m_butt_right.InitBorderColors(this.BorderColor(),this.m_butt_right.BackColorFocused(),this.m_butt_right.BackColorPressed(),this.m_butt_right.BackColorBlocked()); this.m_butt_right.ColorsToDefault(); this.m_butt_right.SetTrimmered(false); this.m_butt_right.SetVisibleInContainer(false); //--- Create a slider int tsz=this.Width()-w*2; this.m_thumb=this.InsertNewElement(ELEMENT_TYPE_SCROLLBAR_THUMB_H,"","ThumbH",w,1,tsz-w*4,h-2); if(this.m_thumb==NULL) { ::PrintFormat("%s: Init failed",__FUNCTION__); return; } //--- Set the slider colors and set its movability flag this.m_thumb.InitBackColors(this.m_thumb.BackColorFocused()); this.m_thumb.ColorsToDefault(); this.m_thumb.InitBorderColors(this.m_thumb.BackColor(),this.m_thumb.BackColorFocused(),this.m_thumb.BackColorPressed(),this.m_thumb.BackColorBlocked()); this.m_thumb.ColorsToDefault(); this.m_thumb.SetMovable(true); this.m_thumb.SetTrimmered(false); this.m_thumb.SetVisibleInContainer(false); //--- Prohibit independent chart redrawing this.m_thumb.SetChartRedrawFlag(false); //--- Initially not displayed in the container this.m_visible_in_container=false; }
我们将在垂直滚动条类中实行完全相同的优化。
//+------------------------------------------------------------------+ //| Vertical scrollbar class | //+------------------------------------------------------------------+ class CScrollBarV : public CPanel { protected: CButtonArrowUp *m_butt_up; // Up arrow button CButtonArrowDown *m_butt_down; // Down arrow button CScrollBarThumbV *m_thumb; // Scrollbar slider public: //--- Return the pointer to the (1) left, (2) right button and (3) slider CButtonArrowUp *GetButtonUp(void) { return this.m_butt_up; } CButtonArrowDown *GetButtonDown(void) { return this.m_butt_down; } CScrollBarThumbV *GetThumb(void) { return this.m_thumb; } //--- (1) Sets and (2) return the chart update flag void SetChartRedrawFlag(const bool flag) { if(this.m_thumb!=NULL) this.m_thumb.SetChartRedrawFlag(flag); } bool ChartRedrawFlag(void) const { return(this.m_thumb!=NULL ? this.m_thumb.ChartRedrawFlag() : false); } //--- Return (1) the track length (2) start and (3) the slider position int TrackLength(void) const; int TrackBegin(void) const; int ThumbPosition(void) const; //--- Set the slider position bool SetThumbPosition(const int pos) const { return(this.m_thumb!=NULL ? this.m_thumb.MoveY(pos) : false); } //--- Change the slider size bool SetThumbSize(const uint size) const { return(this.m_thumb!=NULL ? this.m_thumb.ResizeH(size) : false); } //--- Change the object height virtual bool ResizeH(const int size); //--- Set the flag of visibility in the container virtual void SetVisibleInContainer(const bool flag); //--- Draw the appearance virtual void Draw(const bool chart_redraw); //--- Object type virtual int Type(void) const { return(ELEMENT_TYPE_SCROLLBAR_V); } //--- Initialize (1) the class object and (2) default object colors void Init(void); virtual void InitColors(void); //--- Wheel scroll handler (Wheel) virtual void OnWheelEvent(const int id, const long lparam, const double dparam, const string sparam); //--- Constructors/destructor CScrollBarV(void); CScrollBarV(const string object_name, const string text, const long chart_id, const int wnd, const int x, const int y, const int w, const int h); ~CScrollBarV(void) {} }; //+------------------------------------------------------------------+ //| CScrollBarV::Initialization | //+------------------------------------------------------------------+ void CScrollBarV::Init(void) { //--- Initialize a parent class CPanel::Init(); //--- background - opaque this.SetAlphaBG(255); //--- Frame width and text this.SetBorderWidth(0); this.SetText(""); //--- The element is not clipped by the container borders this.m_trim_flag=false; //--- Create scroll buttons int w=this.Width(); int h=this.Width(); this.m_butt_up = this.InsertNewElement(ELEMENT_TYPE_BUTTON_ARROW_UP, "","ButtU",0,0,w,h); this.m_butt_down= this.InsertNewElement(ELEMENT_TYPE_BUTTON_ARROW_DOWN,"","ButtD",0,this.Height()-w,w,h); if(this.m_butt_up==NULL || this.m_butt_down==NULL) { ::PrintFormat("%s: Init failed",__FUNCTION__); return; } //--- Customize the colors and appearance of the up arrow button this.m_butt_up.SetImageBound(1,0,w-4,h-2); this.m_butt_up.InitBackColors(this.m_butt_up.BackColorFocused()); this.m_butt_up.ColorsToDefault(); this.m_butt_up.InitBorderColors(this.BorderColor(),this.m_butt_up.BackColorFocused(),this.m_butt_up.BackColorPressed(),this.m_butt_up.BackColorBlocked()); this.m_butt_up.ColorsToDefault(); this.m_butt_up.SetTrimmered(false); this.m_butt_up.SetVisibleInContainer(false); //--- Customize the colors and appearance of the down arrow button this.m_butt_down.SetImageBound(1,0,w-4,h-2); this.m_butt_down.InitBackColors(this.m_butt_down.BackColorFocused()); this.m_butt_down.ColorsToDefault(); this.m_butt_down.InitBorderColors(this.BorderColor(),this.m_butt_down.BackColorFocused(),this.m_butt_down.BackColorPressed(),this.m_butt_down.BackColorBlocked()); this.m_butt_down.SetTrimmered(false); this.m_butt_down.SetVisibleInContainer(false); //--- Create a slider int tsz=this.Height()-w*2; this.m_thumb=this.InsertNewElement(ELEMENT_TYPE_SCROLLBAR_THUMB_V,"","ThumbV",1,w,w-2,tsz/2); if(this.m_thumb==NULL) { ::PrintFormat("%s: Init failed",__FUNCTION__); return; } //--- Set the slider colors and set its movability flag this.m_thumb.InitBackColors(this.m_thumb.BackColorFocused()); this.m_thumb.ColorsToDefault(); this.m_thumb.InitBorderColors(this.m_thumb.BackColor(),this.m_thumb.BackColorFocused(),this.m_thumb.BackColorPressed(),this.m_thumb.BackColorBlocked()); this.m_thumb.ColorsToDefault(); this.m_thumb.SetMovable(true); this.m_thumb.SetTrimmered(false); this.m_thumb.SetVisibleInContainer(false); //--- prohibit independent chart redrawing this.m_thumb.SetChartRedrawFlag(false); //--- Initially not displayed in the container this.m_visible_in_container=false; } //+------------------------------------------------------------------+ //| CScrollBarV::Set the flag of visibility in the container | //+------------------------------------------------------------------+ void CScrollBarV::SetVisibleInContainer(const bool flag) { this.m_visible_in_container=flag; if(this.m_butt_up!=NULL) this.m_butt_up.SetVisibleInContainer(flag); if(this.m_butt_down!=NULL) this.m_butt_down.SetVisibleInContainer(flag); if(this.m_thumb!=NULL) this.m_thumb.SetVisibleInContainer(flag); }
在CContainer容器对象类中， 声明新的变量与方法：
//+------------------------------------------------------------------+ //| Container class | //+------------------------------------------------------------------+ class CContainer : public CPanel { private: bool m_visible_scrollbar_h; // Visibility flag for the horizontal scrollbar bool m_visible_scrollbar_v; // Vertical scrollbar visibility flag int m_init_border_size_top; // Initial border size from the top int m_init_border_size_bottom; // Initial border size from the bottom int m_init_border_size_left; // Initial border size from the left int m_init_border_size_right; // Initial border size from the right //--- Return the type of the element that sent the event ENUM_ELEMENT_TYPE GetEventElementType(const string name); protected: CScrollBarH *m_scrollbar_h; // Pointer to the horizontal scrollbar CScrollBarV *m_scrollbar_v; // Pointer to the vertical scrollbar //--- Handler for dragging element edges and corners virtual void ResizeActionDragHandler(const int x, const int y); //--- Check the dimensions of the element to display scrollbars void CheckElementSizes(CElementBase *element); //--- Calculate and return the size (1) of the slider, (2) the full size, (3) the working size of the horizontal scrollbar track int ThumbSizeHorz(void); int TrackLengthHorz(void) const { return(this.m_scrollbar_h!=NULL ? this.m_scrollbar_h.TrackLength() : 0); } int TrackEffectiveLengthHorz(void) { return(this.TrackLengthHorz()-this.ThumbSizeHorz()); } //--- Calculate and return the size (1) of the slider, (2) the full size, (3) the working size of the vertical scrollbar track int ThumbSizeVert(void); int TrackLengthVert(void) const { return(this.m_scrollbar_v!=NULL ? this.m_scrollbar_v.TrackLength() : 0); } int TrackEffectiveLengthVert(void) { return(this.TrackLengthVert()-this.ThumbSizeVert()); } //--- The size of the visible content area (1) horizontally and (2) vertically int ContentVisibleHorz(void) const { return int(this.Width()-this.BorderWidthLeft()-this.BorderWidthRight()); } int ContentVisibleVert(void) const { return int(this.Height()-this.BorderWidthTop()-this.BorderWidthBottom()); } //--- Full content size (1) horizontally and (2) vertically int ContentSizeHorz(void); int ContentSizeVert(void); //--- Content position (1) horizontally and (2) vertically int ContentPositionHorz(void); int ContentPositionVert(void); //--- Calculate and return the amount of content offset (1) horizontally and (2) vertically depending on the slider position int CalculateContentOffsetHorz(const uint thumb_position); int CalculateContentOffsetVert(const uint thumb_position); //--- Calculate and return the slider offset (1) horizontally and (2) vertically depending on the content position int CalculateThumbOffsetHorz(const uint content_position); int CalculateThumbOffsetVert(const uint content_position); //--- Shift the content (1) horizontally and (2) vertically by the specified value bool ContentShiftHorz(const int value); bool ContentShiftVert(const int value); public: //--- Return pointers to scrollbars, buttons, and scrollbar sliders CScrollBarH *GetScrollBarH(void) { return this.m_scrollbar_h; } CScrollBarV *GetScrollBarV(void) { return this.m_scrollbar_v; } CButtonArrowUp *GetScrollBarButtonUp(void) { return(this.m_scrollbar_v!=NULL ? this.m_scrollbar_v.GetButtonUp() : NULL); } CButtonArrowDown *GetScrollBarButtonDown(void) { return(this.m_scrollbar_v!=NULL ? this.m_scrollbar_v.GetButtonDown() : NULL); } CButtonArrowLeft *GetScrollBarButtonLeft(void) { return(this.m_scrollbar_h!=NULL ? this.m_scrollbar_h.GetButtonLeft() : NULL); } CButtonArrowRight*GetScrollBarButtonRight(void) { return(this.m_scrollbar_h!=NULL ? this.m_scrollbar_h.GetButtonRight(): NULL); } CScrollBarThumbH *GetScrollBarThumbH(void) { return(this.m_scrollbar_h!=NULL ? this.m_scrollbar_h.GetThumb() : NULL); } CScrollBarThumbV *GetScrollBarThumbV(void) { return(this.m_scrollbar_v!=NULL ? this.m_scrollbar_v.GetThumb() : NULL); } //--- Set the content scrolling flag void SetScrolling(const bool flag) { this.m_scroll_flag=flag; } //--- Return the visibility flag of the (1) horizontal and (2) vertical scrollbar bool ScrollBarHorzIsVisible(void) const { return this.m_visible_scrollbar_h; } bool ScrollBarVertIsVisible(void) const { return this.m_visible_scrollbar_v; } //--- Return the attached element (the container contents) CElementBase *GetAttachedElement(void) { return this.GetAttachedElementAt(2); } //--- Create and add (1) a new and (2) a previously created element to the list virtual CElementBase *InsertNewElement(const ENUM_ELEMENT_TYPE type,const string text,const string user_name,const int dx,const int dy,const int w,const int h); virtual CElementBase *InsertElement(CElementBase *element,const int dx,const int dy); //--- (1) Display the object on all chart periods and (2) brings the object to the foreground virtual void Show(const bool chart_redraw); virtual void BringToTop(const bool chart_redraw); //--- Draw the appearance virtual void Draw(const bool chart_redraw); //--- Object type virtual int Type(void) const { return(ELEMENT_TYPE_CONTAINER); } //--- Handlers for custom events of the element when hovering, clicking, and scrolling the wheel in the object area virtual void MouseMoveHandler(const int id, const long lparam, const double dparam, const string sparam); virtual void MousePressHandler(const int id, const long lparam, const double dparam, const string sparam); virtual void MouseWheelHandler(const int id, const long lparam, const double dparam, const string sparam); //--- Initialize a class object void Init(void); //--- Constructors/destructor CContainer(void); CContainer(const string object_name, const string text, const long chart_id, const int wnd, const int x, const int y, const int w, const int h); ~CContainer (void) {} };
在初始化方法中，保留边框的原始尺寸：
//+------------------------------------------------------------------+ //| CContainer::Initialization | //+------------------------------------------------------------------+ void CContainer::Init(void) { //--- Initialize the parent object CPanel::Init(); //--- Border width this.SetBorderWidth(0); //--- Save the set border width on each side this.m_init_border_size_top = (int)this.BorderWidthTop(); this.m_init_border_size_bottom= (int)this.BorderWidthBottom(); this.m_init_border_size_left = (int)this.BorderWidthLeft(); this.m_init_border_size_right = (int)this.BorderWidthRight(); //--- Create a horizontal scrollbar this.m_scrollbar_h=dynamic_cast<CScrollBarH *>(CPanel::InsertNewElement(ELEMENT_TYPE_SCROLLBAR_H,"","ScrollBarH",0,this.Height()-DEF_SCROLLBAR_TH-1,this.Width()-1,DEF_SCROLLBAR_TH)); if(m_scrollbar_h!=NULL) { //--- Hide the element and disable independent redrawing of the chart this.m_scrollbar_h.Hide(false); this.m_scrollbar_h.SetChartRedrawFlag(false); } //--- Create a vertical scrollbar this.m_scrollbar_v=dynamic_cast<CScrollBarV *>(CPanel::InsertNewElement(ELEMENT_TYPE_SCROLLBAR_V,"","ScrollBarV",this.Width()-DEF_SCROLLBAR_TH-1,0,DEF_SCROLLBAR_TH,this.Height()-1)); if(m_scrollbar_v!=NULL) { //--- Hide the element and disable independent redrawing of the chart this.m_scrollbar_v.Hide(false); this.m_scrollbar_v.SetChartRedrawFlag(false); } //--- Allow content scrolling this.m_scroll_flag=true; }
显示容器的方法：
//+------------------------------------------------------------------+ //| CContainer::Display the object on all chart periods | //+------------------------------------------------------------------+ void CContainer::Show(const bool chart_redraw) { //--- If the object is already visible, or it should not be displayed in the container, leave if(!this.m_hidden || !this.m_visible_in_container) return; //--- Display the panel CCanvasBase::Show(false); //--- Display attached objects for(int i=0;i<this.m_list_elm.Total();i++) { CElementBase *elm=this.GetAttachedElementAt(i); if(elm!=NULL) { if(elm.Type()==ELEMENT_TYPE_SCROLLBAR_H && !this.m_visible_scrollbar_h) continue; if(elm.Type()==ELEMENT_TYPE_SCROLLBAR_V && !this.m_visible_scrollbar_v) continue; elm.Show(false); } } //--- If specified, redraw the chart if(chart_redraw) ::ChartRedraw(this.m_chart_id); }
首先显示基础面板，再通过遍历附属对象列表循环渲染容器内容；如果滚动条未设置显示标记，则将其排除在外。
将容器置于前景的方法：
//+------------------------------------------------------------------+ //| CContainer::Bring an object to the foreground | //+------------------------------------------------------------------+ void CContainer::BringToTop(const bool chart_redraw) { //--- Bring the panel to the foreground CCanvasBase::BringToTop(false); //--- Bring attached objects to the foreground for(int i=0;i<this.m_list_elm.Total();i++) { CElementBase *elm=this.GetAttachedElementAt(i); if(elm!=NULL) { if(elm.Type()==ELEMENT_TYPE_SCROLLBAR_H && !this.m_visible_scrollbar_h) { elm.Hide(false); continue; } if(elm.Type()==ELEMENT_TYPE_SCROLLBAR_V && !this.m_visible_scrollbar_v) { elm.Hide(false); continue; } elm.BringToTop(false); } } //--- If specified, redraw the chart if(chart_redraw) ::ChartRedraw(this.m_chart_id); }
整体逻辑与之前的方法相似。
完善用于判断元素尺寸以决定是否显示滚动条的方法：
//+------------------------------------------------------------------+ //| CContainer::Checks the dimensions of the element | //| to display scrollbars | //+------------------------------------------------------------------+ void CContainer::CheckElementSizes(CElementBase *element) { //--- If an empty element is passed, scrolling is prohibited or scrollbars are not created, leave if(element==NULL || !this.m_scroll_flag || this.m_scrollbar_h==NULL || this.m_scrollbar_v==NULL) return; //--- Get the element type and, if it is a scrollbar, leave ENUM_ELEMENT_TYPE type=(ENUM_ELEMENT_TYPE)element.Type(); if(type==ELEMENT_TYPE_SCROLLBAR_H || type==ELEMENT_TYPE_SCROLLBAR_V) return; //--- Initialize the scrollbar display flags this.m_visible_scrollbar_h=false; this.m_visible_scrollbar_v=false; //--- If the width of the element is greater than the width of the container visible area, //--- set the flag for displaying the horizontal scrollbar //--- and display flag in the container if(element.Width()>this.ContentVisibleHorz()) { this.m_visible_scrollbar_h=true; this.m_scrollbar_h.SetVisibleInContainer(true); } //--- If the height of the element is greater than the height of the container visible area, //--- set the flag for displaying the vertical scrollbar //--- and display flag in the container if(element.Height()>this.ContentVisibleVert()) { this.m_visible_scrollbar_v=true; this.m_scrollbar_v.SetVisibleInContainer(true); } //--- If both scrollbars should be displayed if(this.m_visible_scrollbar_h && this.m_visible_scrollbar_v) { //--- Adjust the size of both scrollbars to the scrollbar width and //--- set the slider sizes to the new track sizes if(this.m_scrollbar_v.ResizeH(this.Height()-DEF_SCROLLBAR_TH)) this.m_scrollbar_v.SetThumbSize(this.ThumbSizeVert()); if(this.m_scrollbar_h.ResizeW(this.Width() -DEF_SCROLLBAR_TH)) this.m_scrollbar_h.SetThumbSize(this.ThumbSizeHorz()); } //--- If the horizontal scrollbar should be displayed if(this.m_visible_scrollbar_h) { //--- Reduce the size of the visible container window at the bottom by the scrollbar width + 1 pixel this.SetBorderWidthBottom(this.m_scrollbar_h.Height()+1); //--- Adjust the size of the slider to the new size of the scroll bar and //--- move the scrollbar to the foreground, making it visible this.m_scrollbar_h.SetThumbSize(this.ThumbSizeHorz()); int end_track=this.X()+this.m_scrollbar_h.TrackBegin()+this.m_scrollbar_h.TrackLength(); int thumb_right=this.m_scrollbar_h.GetThumb().Right(); if(thumb_right>=end_track) { int pos=end_track-this.ThumbSizeHorz(); this.m_scrollbar_h.SetThumbPosition(pos); } this.m_scrollbar_h.SetVisibleInContainer(true); this.m_scrollbar_h.MoveY(this.Bottom()-DEF_SCROLLBAR_TH); this.m_scrollbar_h.BringToTop(false); } else { //--- Restore the size of the visible container window below, //--- hide the horizontal scrollbar, disable its display in the container //--- and set the height of the vertical scrollbar to the height of the container this.SetBorderWidthBottom(this.m_init_border_size_bottom); this.m_scrollbar_h.Hide(false); this.m_scrollbar_h.SetVisibleInContainer(false); if(this.m_scrollbar_v.ResizeH(this.Height()-1)) this.m_scrollbar_v.SetThumbSize(this.ThumbSizeVert()); } //--- If the vertical scrollbar should be displayed if(this.m_visible_scrollbar_v) { //--- Reduce the size of the visible container window to the right by the scrollbar width + 1 pixel this.SetBorderWidthRight(this.m_scrollbar_v.Width()+1); //--- Adjust the size of the slider to the new size of the scroll bar and //--- move the scrollbar to the foreground, making it visible this.m_scrollbar_v.SetThumbSize(this.ThumbSizeVert()); int end_track=this.Y()+this.m_scrollbar_v.TrackBegin()+this.m_scrollbar_v.TrackLength(); int thumb_bottom=this.m_scrollbar_v.GetThumb().Bottom(); if(thumb_bottom>=end_track) { int pos=end_track-this.ThumbSizeVert(); this.m_scrollbar_v.SetThumbPosition(pos); } this.m_scrollbar_v.SetVisibleInContainer(true); this.m_scrollbar_v.MoveX(this.Right()-DEF_SCROLLBAR_TH); this.m_scrollbar_v.BringToTop(false); } else { //--- Restore the size of the visible container window at the right, //--- hide the vertical scrollbar, disable its display in the container //--- and set the width of the horizontal scrollbar to the width of the container this.SetBorderWidthRight(this.m_init_border_size_right); this.m_scrollbar_v.Hide(false); this.m_scrollbar_v.SetVisibleInContainer(false); if(this.m_scrollbar_h.ResizeW(this.Width()-1)) this.m_scrollbar_h.SetThumbSize(this.ThumbSizeHorz()); } //--- If any of the scrollbars is visible, trim the anchored element to the new dimensions of the visible area if(this.m_visible_scrollbar_h || this.m_visible_scrollbar_v) { element.ObjectTrim(); } }
该方法的逻辑已在代码注释中做出详细说明，我相信不会产生任何疑问。如有任何问题，可随时在文章的评论区提出。
元素边缘与角点拖动处理函数：
//+------------------------------------------------------------------+ //| CContainer::Handler for dragging element edges and corners | //+------------------------------------------------------------------+ void CContainer::ResizeActionDragHandler(const int x, const int y) { //--- Check the validity of the scrollbars if(this.m_scrollbar_h==NULL || this.m_scrollbar_v==NULL) return; //--- Depending on the region of interaction with the cursor switch(this.ResizeRegion()) { //--- Resize beyond the right border case CURSOR_REGION_RIGHT : //--- If the new width is successfully set if(this.ResizeZoneRightHandler(x,y)) { //--- check the size of the container contents for displaying scrollbars, //--- shift the content to the new position of the horizontal scrollbar slider this.CheckElementSizes(this.GetAttachedElement()); this.ContentShiftHorz(this.m_scrollbar_h.ThumbPosition()); } break; //--- Resize beyond the bottom border case CURSOR_REGION_BOTTOM : //--- If the new height is successfully set if(this.ResizeZoneBottomHandler(x,y)) { //--- check the size of the container contents for displaying scrollbars, //--- shift the content to the new position of the vertical scrollbar slider this.CheckElementSizes(this.GetAttachedElement()); this.ContentShiftVert(this.m_scrollbar_v.ThumbPosition()); } break; //--- Resize beyond the left border case CURSOR_REGION_LEFT : //--- If the new X coordinate and width are successfully set if(this.ResizeZoneLeftHandler(x,y)) { //--- check the size of the container contents for displaying scrollbars, //--- shift the content to the new position of the horizontal scrollbar slider this.CheckElementSizes(this.GetAttachedElement()); this.ContentShiftHorz(this.m_scrollbar_h.ThumbPosition()); } break; //--- Resize beyond the upper border case CURSOR_REGION_TOP : //--- If the new X coordinate and height are successfully set if(this.ResizeZoneTopHandler(x,y)) { //--- check the size of the container contents for displaying scrollbars, //--- shift the content to the new position of the vertical scrollbar slider this.CheckElementSizes(this.GetAttachedElement()); this.ContentShiftVert(this.m_scrollbar_v.ThumbPosition()); } break; //--- Resize by the lower right corner case CURSOR_REGION_RIGHT_BOTTOM : //--- If the new width and height are successfully set if(this.ResizeZoneRightBottomHandler(x,y)) { //--- check the size of the container contents for displaying scrollbars, //--- shift the content to the new positions of the scrollbar sliders this.CheckElementSizes(this.GetAttachedElement()); this.ContentShiftHorz(this.m_scrollbar_h.ThumbPosition()); this.ContentShiftVert(this.m_scrollbar_v.ThumbPosition()); } break; //--- Resize by the upper right corner case CURSOR_REGION_RIGHT_TOP : //--- If the new Y coordinate, width, and height are successfully set if(this.ResizeZoneRightTopHandler(x,y)) { //--- check the size of the container contents for displaying scrollbars, //--- shift the content to the new positions of the scrollbar sliders this.CheckElementSizes(this.GetAttachedElement()); this.ContentShiftHorz(this.m_scrollbar_h.ThumbPosition()); this.ContentShiftVert(this.m_scrollbar_v.ThumbPosition()); } break; //--- Resize by the lower left corner case CURSOR_REGION_LEFT_BOTTOM : //--- If the new X coordinate, width, and height are successfully set if(this.ResizeZoneLeftBottomHandler(x,y)) { //--- check the size of the container contents for displaying scrollbars, //--- shift the content to the new positions of the scrollbar sliders this.CheckElementSizes(this.GetAttachedElement()); this.ContentShiftHorz(this.m_scrollbar_h.ThumbPosition()); this.ContentShiftVert(this.m_scrollbar_v.ThumbPosition()); } break; //--- Resize by the upper left corner case CURSOR_REGION_LEFT_TOP : //--- If the new X and Y coordinate, width, and height are successfully set if(this.ResizeZoneLeftTopHandler(x,y)) {} { //--- check the size of the container contents for displaying scrollbars, //--- shift the content to the new positions of the scrollbar sliders this.CheckElementSizes(this.GetAttachedElement()); this.ContentShiftHorz(this.m_scrollbar_h.ThumbPosition()); this.ContentShiftVert(this.m_scrollbar_v.ThumbPosition()); } break; //--- By default - leave default: return; } ::ChartRedraw(this.m_chart_id); }
这里，根据元素被调整尺寸（及坐标）的边缘或角点，会调用对应边缘或角点拖动的尺寸调整处理函数。当处理程序执行成功后，会根据滚动条滑块的位置，重新调整容器内容的新位置。
以上就是实现通过鼠标光标调整元素尺寸所需的全部优化。本文未涉及一些细微的代码修正与改动，它们仅用于优化代码可读性、方法逻辑，以及鼠标与元素交互时的部分视觉效果。所有修改内容请参考文章所附代码。
测试结果
测试时，在终端目录\MQL5\Indicators\下的Tables\子文件夹中，新建一个名为iTestResize.mq5的指标文件：
//+------------------------------------------------------------------+ //| iTestResize.mq5 | //| Copyright 2025, MetaQuotes Ltd. | //| https://www.mql5.com | //+------------------------------------------------------------------+ #property copyright "Copyright 2025, MetaQuotes Ltd." #property link "https://www.mql5.com" #property version "1.00" #property indicator_separate_window #property indicator_buffers 0 #property indicator_plots 0 //+------------------------------------------------------------------+ //| Include libraries | //+------------------------------------------------------------------+ #include "Controls\Controls.mqh" // Controls library CContainer *container=NULL; // Pointer to the Container graphical element //+------------------------------------------------------------------+ //| Custom indicator initialization function | //+------------------------------------------------------------------+ int OnInit() { //--- Search for the chart subwindow int wnd=ChartWindowFind(); //--- Create "Container" graphical element container=new CContainer("Container","",0,wnd,100,40,300,200); if(container==NULL) return INIT_FAILED; //--- Set the container parameters container.SetID(1); // ID container.SetAsMain(); // The chart should have one main element container.SetBorderWidth(1); // Border width (one pixel margin on each side of the container) container.SetResizable(true); // Ability to resize by dragging edges and corners container.SetName("Main container"); // Name //--- Attach the GroupBox element to the container CGroupBox *groupbox=container.InsertNewElement(ELEMENT_TYPE_GROUPBOX,"","Attached Groupbox",4,4,container.Width()*2+20,container.Height()*3+10); if(groupbox==NULL) return INIT_FAILED; groupbox.SetGroup(1); // Group index //--- In a loop, create and attach 30 rows of "Text label" elements to the GroupBox element for(int i=0;i<30;i++) { string text=StringFormat("This is test line number %d to demonstrate how scrollbars work when scrolling the contents of the container.",(i+1)); int len=groupbox.GetForeground().TextWidth(text); CLabel *lbl=groupbox.InsertNewElement(ELEMENT_TYPE_LABEL,text,"TextString"+string(i+1),8,8+(20*i),len,20); if(lbl==NULL) return INIT_FAILED; } //--- Draw all created elements on the chart and display their description in the journal container.Draw(true); container.Print(); //--- Successful return(INIT_SUCCEEDED); } //+------------------------------------------------------------------+ //| Custom deindicator initialization function | //+------------------------------------------------------------------+ void OnDeinit(const int reason) { //--- Remove the Container element and destroy the library's shared resource manager delete container; CCommonManager::DestroyInstance(); } //+------------------------------------------------------------------+ //| Custom indicator iteration function | //+------------------------------------------------------------------+ int OnCalculate(const int rates_total, const int prev_calculated, const datetime &time[], const double &open[], const double &high[], const double &low[], const double &close[], const long &tick_volume[], const long &volume[], const int &spread[]) { //--- //--- return value of prev_calculated for the next call return(rates_total); } //+------------------------------------------------------------------+ //| ChartEvent function | //+------------------------------------------------------------------+ void OnChartEvent(const int id, const long &lparam, const double &dparam, const string &sparam) { //--- Call the OnChartEvent handler of the Container element container.OnChartEvent(id,lparam,dparam,sparam); } //+------------------------------------------------------------------+ //| Timer | //+------------------------------------------------------------------+ void OnTimer(void) { //--- Call the OnTimer handler of the Container element container.OnTimer(); }
该指标与前一篇文章中的测试指标基本无差别。
编译该指标并在图表上运行：
很明显，文中所述功能均可正常运行。较难精准选中元素与滚动条相接的边缘区域。然而，可调整尺寸的图形组件通常不会由单一控件构成，以图形组件“窗体（Form）”为例，它和内部所有控件之间留有充足的边距，借此我们能轻松找到拖拽元素边界的鼠标抓取点。
目前仍存在少量缺陷，后续开发TableView图形组件时，我们会逐步完善修复。
结论
如今我们距离完成TableView控件开发又近了一步，该控件能够在程序中创建并展示表格数据。视图组件的实现逻辑量大且复杂，但完成后基本可以满足绝大多数表格数据展示与交互操作的需求。
在下一篇文章中，我们将着手开发交互式表格表头，实现对表格行列的管理功能。
本文中使用的程序：
| # | 名称 | 类型 | 描述 |
|---|---|---|---|
| 1 | Base.mqh | 类库 | 创建控件基础对象的类 |
| 2 | Controls.mqh | 类库 | 控制类 |
| 3 | iTestResize.mq5 | 测试指标 | 测试控件类操作的指标 |
| 4 | MQL5.zip | 归档 | 以上供解压到客户端终端MQL5目录的文件存档 |
所有创建的文件均随附于本文，供读者自学使用。该压缩文件可解压至终端文件夹，所有文件将自动放置于目标文件夹：\MQL5\Indicators\Tables\。
本文由MetaQuotes Ltd译自俄文
原文地址： https://www.mql5.com/ru/articles/18941
注意: MetaQuotes Ltd.将保留所有关于这些材料的权利。全部或部分复制或者转载这些材料将被禁止。
本文由网站的一位用户撰写，反映了他们的个人观点。MetaQuotes Ltd 不对所提供信息的准确性负责，也不对因使用所述解决方案、策略或建议而产生的任何后果负责。
最近评论 |
前往讨论
(2)
EDYMAURICIO ALGUAPEREZ
|
7 6月 2026 在 01:07
我用不了
Miguel Angel Vico Alba
|
8 6月 2026 在 06:55
EDYMAURICIO ALGUAPEREZ #: 我用不了
能否具体描述一下哪里无法正常工作？
价格行为分析工具包开发（第34部分）：借助高级数据采集管道将原始市场数据转化为预测模型
你是否曾错过市场突然的尖峰行情，或者在行情发生时措手不及？预判实时行情的最佳方法是从历史形态中学习。为了训练一个机器学习模型，本文首先向您展示如何在 MetaTrader 5 中创建一个脚本，用于摄取历史数据并将其发送到 Python 进行存储 —— 为您的尖峰检测系统奠定基础。继续阅读，了解每个步骤的实际操作。
新手在交易中的10个基本错误
新手在交易中会犯的10个基本错误: 在市场刚开始时交易, 获利时不适当地仓促, 在损失的时候追加投资, 从最好的仓位开始平仓, 翻本心理, 最优越的仓位, 用永远买进的规则进行交易, 在第一天就平掉获利的仓位,当发出建一个相反的仓位警示时平仓, 犹豫。
使用机器学习检测与分类分形模式
在本文中，我们将探讨一个有趣的话题：利用机器学习进行分形分析和市场预测。这只是迈向探索金融价格图表上形成的各种分形结构的最初几步。我们将利用相关性来发现模式，并使用 CatBoost 算法对这些模式进行分类。
