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Graphics in DoEasy library (Part 98): Moving pivot points of extended standard graphical objects

Graphics in DoEasy library (Part 98): Moving pivot points of extended standard graphical objects

MetaTrader 5Examples | 5 May 2022, 16:33
3 548 0
Artyom Trishkin
Artyom Trishkin

Contents


Concept

In the article 93, I started the development of composite graphical objects in the library. Then I was distracted by the necessity to improve the functionality of form objects based on the CCanvas class. We use the form objects in the composite graphical objects for creating pivot point controls of a graphical object included into an extended standard graphical object. So we have been in need for the new form object functionality.

In the previous article, I completed the improvement of objects based on the CCanvas class. Today, I will continue the development of extended standard graphical objects the composite graphical objects consist of.

The article objective is not a development of new classes. Instead, I will consider the improvement of the already prepared functionality for creating convenient tools for relocating pivot points of standard graphical objects. The article will describe the development of a composite graphical object prototype. We already created it in the previous articles. This is an ordinary trend line with additional price label objects at its ends:


Today I will deal with the issue of moving trend line pivot points together with price labels attached to the relocated side of the trend line. The line pivot points contain form objects for relocation. By grabbing and moving the object, we will move the appropriate trend line side as well. While the cursor is away from the trend line pivot point, the form object remains invisible. However, when the cursor approaches the pivot point at a certain distance (when entering the area of a completely transparent form), points with circles appear on the form:


This is how the trend line pivot point control appears on the chart. The form has the greater size than its active area. The active area of a form is the area that can be dragged to move the form. In contrast, the area of the form itself can be used to arrange other kinds of interaction with it using mouse buttons and mouse wheel.

Thus, if the mouse cursor is within the form but is outside its active area, we can implement, for example, the activation of the context menu of a composite graphical object upon pressing the right mouse button. If the cursor is in the active area, then, in addition to the context menu, we can grab this form with the mouse and move it. In this case, the end of the line the form is attached to moves as well.

Of course, this is just a test composite graphical object used to give the new functionality a try. After all the necessary tools for creating composite graphical objects and for processing form objects are created, I will create a small set of standard library composite graphical objects to be used to develop custom objects. Their creation will serve as an example and description of how to create your own objects of this kind.

For now, I am only developing the functionality of the library and create the necessary "bricks" to make custom objects from. The steps described, analyzed and implemented in my articles will serve as basis to be used 'as is' without the need to implement everything from scratch.


Improving library classes

Open \MQL5\Include\DoEasy\Defines.mqh and implement some changes.

The pivot point control forms are to contain a point and a circle. The applied color has previously been specified right in the code. Let's add the macro substitution featuring the default color:

//--- Pending request type IDs
#define PENDING_REQUEST_ID_TYPE_ERR    (1)                        // Type of a pending request created based on the server return code
#define PENDING_REQUEST_ID_TYPE_REQ    (2)                        // Type of a pending request created by request
//--- Timeseries parameters
#define SERIES_DEFAULT_BARS_COUNT      (1000)                     // Required default amount of timeseries data
#define PAUSE_FOR_SYNC_ATTEMPTS        (16)                       // Amount of pause milliseconds between synchronization attempts
#define ATTEMPTS_FOR_SYNC              (5)                        // Number of attempts to receive synchronization with the server
//--- Tick series parameters
#define TICKSERIES_DEFAULT_DAYS_COUNT  (1)                        // Required number of days for tick data in default series
#define TICKSERIES_MAX_DATA_TOTAL      (200000)                   // Maximum number of stored tick data of a single symbol
//--- Parameters of the DOM snapshot series
#define MBOOKSERIES_DEFAULT_DAYS_COUNT (1)                        // The default required number of days for DOM snapshots in the series
#define MBOOKSERIES_MAX_DATA_TOTAL     (200000)                   // Maximum number of stored DOM snapshots of a single symbol
//--- Canvas parameters
#define PAUSE_FOR_CANV_UPDATE          (16)                       // Canvas update frequency
#define CLR_CANV_NULL                  (0x00FFFFFF)               // Zero for the canvas with the alpha channel
#define OUTER_AREA_SIZE                (16)                       // Size of one side of the outer area around the form workspace
//--- Graphical object parameters
#define PROGRAM_OBJ_MAX_ID             (10000)                    // Maximum value of an ID of a graphical object belonging to a program
#define CTRL_POINT_RADIUS              (5)                        // Radius of the control point on the form for managing graphical object pivot points
#define CTRL_POINT_COLOR               (clrDodgerBlue)            // Radius of the control point on the form for managing graphical object pivot points
#define CTRL_FORM_SIZE                 (40)                       // Size of the control point form for managing graphical object pivot points
//+------------------------------------------------------------------+
//| Enumerations                                                     |
//+------------------------------------------------------------------+

Rename the CTRL_POINT_SIZE macro substitution into CTRL_POINT_RADIUS since this is not its full size of the circle, but its radius. The macro substitution name was a little misleading when calculating the active area of the form object.

In the file of the graphical element object class \MQL5\Include\DoEasy\Objects\Graph\GCnvElement.mqh, slightly improve the method of creating a graphical element object. Unfortunately, there is no returning of the error code when calling the CreateBitmapLabel() method of the CCanvas class. Therefore, reset the last error code before calling the method. If failed to create a graphical label, display the error code in the journal. This slightly improves debugging.

//+------------------------------------------------------------------+
//| Create the graphical element object                              |
//+------------------------------------------------------------------+
bool CGCnvElement::Create(const long chart_id,     // Chart ID
                          const int wnd_num,       // Chart subwindow
                          const string name,       // Element name
                          const int x,             // X coordinate
                          const int y,             // Y coordinate
                          const int w,             // Width
                          const int h,             // Height
                          const color colour,      // Background color
                          const uchar opacity,     // Opacity
                          const bool redraw=false) // Flag indicating the need to redraw
                         
  {
   ::ResetLastError();
   if(this.m_canvas.CreateBitmapLabel(chart_id,wnd_num,name,x,y,w,h,COLOR_FORMAT_ARGB_NORMALIZE))
     {
      this.Erase(CLR_CANV_NULL);
      this.m_canvas.Update(redraw);
      this.m_shift_y=(int)::ChartGetInteger(chart_id,CHART_WINDOW_YDISTANCE,wnd_num);
      return true;
     }
   CMessage::ToLog(DFUN,::GetLastError(),true);
   return false;
  }
//+------------------------------------------------------------------+

Why did I have to do this? When creating form objects, I spent a lot of time trying to understand why I am unable to create a graphical resource. Finally, it turned out that the created name of a graphical resource exceeded 63 characters. If the method for creating a graphical label of the CCanvas class reported the error, we would not have to search for anything. Instead, we would immediately get the error code and I would not have to pass along all loops of calling various methods in different classes.

However, this improvement will be of no help if the reosurce name length exceeds 63 characters:

ERR_RESOURCE_NAME_IS_TOO_LONG     4018     The resource name exceeds 63 characters

returning the error code

ERR_RESOURCE_NOT_FOUND    4016    Resource with such a name is not found in EX5

but this is still better as this immediately provokes the question: "Why is the graphical resource not created?"...


Let's make improvements in the file of the extended standard graphical object toolkit class in the file \MQL5\Include\DoEasy\Objects\Graph\Extend\CGStdGraphObjExtToolkit.mqh.

Each graphical object features one or several pivot points used to position the object on a chart. A form object is attached to each of the points. Standard graphical objects have their own points for relocation. They appear when selecting a graphical object. We are not going to manage extended standard graphical objects in the library. To implement the functionality, it will be more convenient for us to use form objects to move pivot points of graphical objects. There may be more such form objects than control points. Therefore, we cannot define the number of form objects by the number of pivot points of a graphical object. However, we need to know this number. Therefore, in the public section of the class, add the method returning the number of created form objects for managing pivot points and declare the method drawing the points of managing pivot points on fully transparent form objects:

//--- (1) Set and (2) return the size of the form of pivot point management control points
   void              SetControlFormSize(const int size);
   int               GetControlFormSize(void)                           const { return this.m_ctrl_form_size;                 }
//--- Return the pointer to the pivot point form by (1) index and (2) name
   CForm            *GetControlPointForm(const int index)                     { return this.m_list_forms.At(index);           }
   CForm            *GetControlPointForm(const string name,int &index);
//--- Return the number of (1) base object pivot points and (2) newly created form objects for managing reference points
   int               GetNumPivotsBaseObj(void)                          const { return this.m_base_pivots;                    }
   int               GetNumControlPointForms(void)                      const { return this.m_list_forms.Total();             }
//--- Create form objects on the base object pivot points
   bool              CreateAllControlPointForm(void);
//--- Draw a reference point on the form
   void              DrawControlPoint(CForm *form,const uchar opacity,const color clr);
//--- Remove all form objects from the list
   void              DeleteAllControlPointForm(void);


In the method creating a form object on the base object pivot point, shorten the name of a created object replace "_TKPP_" with "_CP_":

//+------------------------------------------------------------------+
//| Create a form object on a base object reference point            |
//+------------------------------------------------------------------+
CForm *CGStdGraphObjExtToolkit::CreateNewControlPointForm(const int index)
  {
   string name=this.m_base_name+"_CP_"+(index<this.m_base_pivots ? (string)index : "X");
   CForm *form=this.GetControlPointForm(index);
   if(form!=NULL)
      return NULL;
   int x=0, y=0;
   if(!this.GetControlPointCoordXY(index,x,y))
      return NULL;
   return new CForm(this.m_base_chart_id,this.m_base_subwindow,name,x-this.m_shift,y-this.m_shift,this.GetControlFormSize(),this.GetControlFormSize());
  }
//+------------------------------------------------------------------+

Here (and in the test EA file) I had to shorten the name of the created form object since the name of the graphical resource exceeded 63 characters and no object was created. The reason lies in the dynamic resource creation method in the CCanvas class, where the name of the created resource consists of "::" symbols + the name passed to the method (and specified in the method described above) + chart ID + number of milliseconds passed since the system start + pseudo random number:

//+------------------------------------------------------------------+
//| Create dynamic resource                                          |
//+------------------------------------------------------------------+
bool CCanvas::Create(const string name,const int width,const int height,ENUM_COLOR_FORMAT clrfmt)
  {
   Destroy();
//--- prepare data array
   if(width>0 && height>0 && ArrayResize(m_pixels,width*height)>0)
     {
      //--- generate resource name
      m_rcname="::"+name+(string)ChartID()+(string)(GetTickCount()+MathRand());
      //--- initialize data with zeros
      ArrayInitialize(m_pixels,0);
      //--- create dynamic resource
      if(ResourceCreate(m_rcname,m_pixels,width,height,0,0,0,clrfmt))
        {
         //--- successfully created
         //--- complete initialization
         m_width =width;
         m_height=height;
         m_format=clrfmt;
         //--- succeed
         return(true);
        }
     }
//--- error - destroy object
   Destroy();
   return(false);
  }
//+------------------------------------------------------------------+

Unfortunately, all this imposes serious restrictions on selecting an apprehensible name for the created object.

In the method creating form objects on the base object pivot points, calculate the indent from each side of the form object for specifying the location and size of the form active area which is to be located in the center of the form, while its size should be equal to the two values set in the CTRL_POINT_RADIUS macro substitution. Since we are dealing with the radius, we need to use two radius values, subtract them from the form width (the form height is equal to its width) and divide the obtained value by two so that the form active area is equal to the circle drawn in its center.
Specify the active area border indent from the form edge in the SetActiveAreaShift() method:

//+------------------------------------------------------------------+
//| Create form objects on the base object pivot points              |
//+------------------------------------------------------------------+
bool CGStdGraphObjExtToolkit::CreateAllControlPointForm(void)
  {
   bool res=true;
   //--- In the loop by the number of base object pivot points
   for(int i=0;i<this.m_base_pivots;i++)
     {
      //--- Create a new form object on the current pivot point corresponding to the loop index
      CForm *form=this.CreateNewControlPointForm(i);
      //--- If failed to create the form, inform of that and add 'false' to the final result
      if(form==NULL)
        {
         CMessage::ToLog(DFUN,MSG_GRAPH_OBJ_EXT_FAILED_CREATE_CTRL_POINT_FORM);
         res &=false;
        }
      //--- If failed to add the form to the list, inform of that, remove the created form and add 'false' to the final result
      if(!this.m_list_forms.Add(form))
        {
         CMessage::ToLog(DFUN,MSG_LIB_SYS_FAILED_OBJ_ADD_TO_LIST);
         delete form;
         res &=false;
        }
      //--- Set all the necessary properties for the created form object
      form.SetBelong(GRAPH_OBJ_BELONG_PROGRAM);                // Object is created programmatically
      form.SetActive(true);                                    // Form object is active
      form.SetMovable(true);                                   // Movable object
      int x=(int)::floor((form.Width()-CTRL_POINT_RADIUS*2)/2);// Active area shift from the form edge
      form.SetActiveAreaShift(x,x,x,x);                        // Object active area is located in the center of the form, its size is equal to the two CTRL_POINT_RADIUS values
      form.SetFlagSelected(false,false);                       // Object is not selected
      form.SetFlagSelectable(false,false);                     // Object cannot be selected by mouse
      form.Erase(CLR_CANV_NULL,0);                             // Fill in the form with transparent color and set the full transparency
      //form.DrawRectangle(0,0,form.Width()-1,form.Height()-1,clrSilver);    // Draw an outlining rectangle for visual display of the form location
      //form.DrawRectangle(x,x,form.Width()-x-1,form.Height()-x-1,clrSilver);// Draw an outlining rectangle for visual display of the form active area location
      this.DrawControlPoint(form,0,CTRL_POINT_COLOR);          // Draw a circle and a point in the form center
      form.Done();                                             // Save the initial form object state (its appearance)
     }
   //--- Redraw the chart for displaying changes (if successful) and return the final result
   if(res)
      ::ChartRedraw(this.m_base_chart_id);
   return res;
  }
//+------------------------------------------------------------------+

When creating the form, we are able to draw rectangles displaying the size of the form and its active area for debugging — these strings have been commented out. Use the new method considered below to draw the completely transparent circles at the center of the form (but is it a good idea to draw them at all?).

The method drawing a reference point on the form:

//+------------------------------------------------------------------+
//| Draw a reference point on the form                               |
//+------------------------------------------------------------------+
void CGStdGraphObjExtToolkit::DrawControlPoint(CForm *form,const uchar opacity,const color clr)
  {
   if(form==NULL)
      return;
   form.DrawCircle((int)::floor(form.Width()/2),(int)::floor(form.Height()/2),CTRL_POINT_RADIUS,clr,opacity);// Draw a circle at the center of the form
   form.DrawCircleFill((int)::floor(form.Width()/2),(int)::floor(form.Height()/2),2,clr,opacity);            // Draw a point at the center of the form
  }
//+------------------------------------------------------------------+

The method contains two strings taken from the method considered above. Why? We need to either show or hide a point with a circle at the center of the form at various points in time. To achieve this, we will call the method by specifying the necessary non-transparency and color of shapes being drawn.

Remove handling the mouse cursor movement from the event handler as it is no longer needed:

//+------------------------------------------------------------------+
//| Event handler                                                    |
//+------------------------------------------------------------------+
void CGStdGraphObjExtToolkit::OnChartEvent(const int id,const long& lparam,const double& dparam,const string& sparam)
  {
   if(id==CHARTEVENT_CHART_CHANGE)
     {
      for(int i=0;i<this.m_list_forms.Total();i++)
        {
         CForm *form=this.m_list_forms.At(i);
         if(form==NULL)
            continue;
         int x=0, y=0;
         if(!this.GetControlPointCoordXY(i,x,y))
            continue;
         form.SetCoordX(x-this.m_shift);
         form.SetCoordY(y-this.m_shift);
         form.Update();
        }
      ::ChartRedraw(this.m_base_chart_id);
     }
   if(id==CHARTEVENT_MOUSE_MOVE)
     {
      for(int i=0;i<this.m_list_forms.Total();i++)
        {
         CForm *form=this.m_list_forms.At(i);
         if(form==NULL)
            continue;
         form.OnChartEvent(id,lparam,dparam,sparam);
        }
      ::ChartRedraw(this.m_base_chart_id);
     }
  }
//+------------------------------------------------------------------+


Improve the abstract standard graphical object class in \MQL5\Include\DoEasy\Objects\Graph\Standard\GStdGraphObj.mqh.

In the public section of the class, declare the method allowing us to change the coordinates of the graphical object pivot points and of the objects bound to it simultaneously:

//--- Return (1) the list of dependent objects, (2) dependent graphical object by index and (3) the number of dependent objects
   CArrayObj        *GetListDependentObj(void)        { return &this.m_list;           }
   CGStdGraphObj    *GetDependentObj(const int index) { return this.m_list.At(index);  }
   int               GetNumDependentObj(void)         { return this.m_list.Total();    }
//--- Return the name of the dependent object by index
   string            NameDependent(const int index);
//--- Add the dependent graphical object to the list
   bool              AddDependentObj(CGStdGraphObj *obj);
//--- Change X and Y coordinates of the current and all dependent objects
   bool              ChangeCoordsExtendedObj(const int x,const int y,const int modifier,bool redraw=false);
//--- Return the object of data on pivot points
   CLinkedPivotPoint*GetLinkedPivotPoint(void)        { return &this.m_linked_pivots;  }

Declare three methods to access the form for managing graphical object pivot points:

//--- Return the number of base object pivot points for calculating the coordinates in the (1) current and (2) specified object
   int               GetLinkedCoordsNum(void)               const { return this.m_linked_pivots.GetNumLinkedCoords();      }
   int               GetLinkedPivotsNum(CGStdGraphObj *obj) const { return(obj!=NULL ? obj.GetLinkedCoordsNum() : 0);      }
//--- Return the form for managing an object pivot point
   CForm            *GetControlPointForm(const int index);
//--- Return the number of form objects for managing reference points
   int               GetNumControlPointForms(void);
//--- Redraw the form for managing a reference point of an extended standard graphical object
   void              RedrawControlPointForms(const uchar opacity,const color clr);

private:


Add the method setting the time and price by screen coordinates:

//--- Symbol for the Chart object 
   string            ChartObjSymbol(void)          const { return this.GetProperty(GRAPH_OBJ_PROP_CHART_OBJ_SYMBOL,0);                    }
   bool              SetChartObjSymbol(const string symbol)
                       {
                        if(!::ObjectSetString(CGBaseObj::ChartID(),CGBaseObj::Name(),OBJPROP_SYMBOL,symbol))
                           return false;
                        this.SetProperty(GRAPH_OBJ_PROP_CHART_OBJ_SYMBOL,0,symbol);
                        return true;
                       }
//--- Set the time and price by screen coordinates
   bool              SetTimePrice(const int x,const int y,const int modifier)
                       {
                        bool res=true;
                        ENUM_OBJECT type=this.GraphObjectType();
                        if(type==OBJ_LABEL || type==OBJ_BUTTON || type==OBJ_BITMAP_LABEL || type==OBJ_EDIT || type==OBJ_RECTANGLE_LABEL)
                          {
                           res &=this.SetXDistance(x);
                           res &=this.SetYDistance(y);
                          }
                        else
                          {
                           int subwnd=0;
                           datetime time=0;
                           double price=0;
                           if(::ChartXYToTimePrice(this.ChartID(),x,y,subwnd,time,price))
                             {
                              res &=this.SetTime(time,modifier);
                              res &=this.SetPrice(price,modifier);
                             }
                          }
                        return res;
                       }
  
//--- Return the flags indicating object visibility on timeframes

We need to recalculate screen coordinates into time/price coordinates to be able to handle graphical objects in X and Y screen coordinates. The method first checks the current object type. If it is constructed based on the screen coordinates, its screen coordinates change immediately. If the graphical object is based on time/price coordinates, we first need to convert the screen coordinates passed to the method into time and price values. The obtained values are then set in the graphical object parameters.

The method returning the form for managing the object pivot point:

//+------------------------------------------------------------------+
//| Return the form for managing an object pivot point               |
//+------------------------------------------------------------------+
CForm *CGStdGraphObj::GetControlPointForm(const int index)
  {
   return(this.ExtToolkit!=NULL ? this.ExtToolkit.GetControlPointForm(index) : NULL);
  }
//+------------------------------------------------------------------+

Here all is simple: if the object of the extended standard graphical object toolkit exists, the form object by index is returned. Otherwise, return NULL.

The method returning the number of form objects for managing reference points:

//+------------------------------------------------------------------+
//| Return the number of form objects                                |
//| for managing control points                                      |
//+------------------------------------------------------------------+
int CGStdGraphObj::GetNumControlPointForms(void)
  {
   return(this.ExtToolkit!=NULL ? this.ExtToolkit.GetNumControlPointForms() : 0);
  }
//+------------------------------------------------------------------+

The method is similar to the one described above: if the object of the extended standard graphical object toolkit exists, the number of form objects is returned. Otherwise, return 0.

The method redrawing the form for managing a reference point of an extended standard graphical object:

//+------------------------------------------------------------------+
//| Redraw the form for managing the control point                   |
//| of the extended standard graphical object                        |
//+------------------------------------------------------------------+
void CGStdGraphObj::RedrawControlPointForms(const uchar opacity,const color clr)
  {
//--- If the object has no extended standard graphical object toolkit, exit
   if(this.ExtToolkit==NULL)
      return;
//--- Get the number of pivot point handling forms
   int total_form=this.GetNumControlPointForms();
//--- In the loop by the number of pivot point management forms
   for(int i=0;i<total_form;i++)
     {
      //--- get the next form object
      CForm *form=this.ExtToolkit.GetControlPointForm(i);
      if(form==NULL)
         continue;
      //--- draw a point and a circle with the specified non-transparency and color
      this.ExtToolkit.DrawControlPoint(form,opacity,clr);
     }
   
//--- Get the total number of bound graphical objects
   int total_dep=this.GetNumDependentObj();
//--- In the loop by all bound graphical objects,
   for(int i=0;i<total_dep;i++)
     {
      //--- get the next graphical object from the list
      CGStdGraphObj *dep=this.GetDependentObj(i);
      if(dep==NULL)
         continue;
      //--- call the method for it
      dep.RedrawControlPointForms(opacity,clr);
     }
  }
//+------------------------------------------------------------------+

The method is accompanied by detailed comments. Briefly, the idea is as follows: first, we redraw all form objects bound to the current object. As we know, dependent graphical objects can be attached to the object. These dependent objects also have form objects of their own. Therefore, let's call this method for each of the dependent objects in the loop by all dependent objects. In turn, the dependent objects loop over the list of their own dependent objects and call the same method for them. This is done till all form objects for all linked graphical objects are redrawn.

The method changing X and Y coordinates of the current and all dependent objects:

//+----------------------------------------------------------------------+
//| Change X and Y coordinates of the current and all dependent objects  |
//+----------------------------------------------------------------------+
bool CGStdGraphObj::ChangeCoordsExtendedObj(const int x,const int y,const int modifier,bool redraw=false)
  {
//--- Set the new coordinates for the pivot point set in 'modifier'
   if(!this.SetTimePrice(x,y,modifier))
      return false;
//--- If the object is not a composite graphical object
//--- or dependent graphical objects are not attached to the object,
//--- there is nothing we can do here, return 'true'
   if(this.ExtToolkit==NULL || this.m_list.Total()==0)
      return true;
//--- Get the graphical object bound to the 'modifier' point
   CGStdGraphObj *dep=this.GetDependentObj(modifier);
   if(dep==NULL)
      return false;
//--- Get the object of the pivot point data of the attached graphical object
   CLinkedPivotPoint *pp=dep.GetLinkedPivotPoint();
   if(pp==NULL)
      return false;
//--- get the number of coordinate points the object is attached to
   int num=pp.GetNumLinkedCoords();
//--- In the loop by the object coordinate points,
   for(int j=0;j<num;j++)
     {
      //--- get the number of coordinate points of the base object for setting the X coordinate
      int numx=pp.GetBasePivotsNumX(j);
      //--- In the loop by each coordinate point for setting the X coordinate,
      for(int nx=0;nx<numx;nx++)
        {
         //--- get the property for setting the X coordinate, its modifier
         //--- and set it to the dependent graphical object attached to the 'modifier' point
         int prop_from=pp.GetPropertyX(j,nx);
         int modifier_from=pp.GetPropertyModifierX(j,nx);
         this.SetCoordXToDependentObj(dep,prop_from,modifier_from,nx);
        }
      //--- Get the number of coordinate points of the base object for setting the Y coordinate
      int numy=pp.GetBasePivotsNumY(j);
      //--- In the loop by each coordinate point for setting the Y coordinate,
      for(int ny=0;ny<numy;ny++)
        {
         //--- get the property for setting the Y coordinate, its modifier
         //--- and set it to the dependent graphical object attached to the 'modifier' point
         int prop_from=pp.GetPropertyY(j,ny);
         int modifier_from=pp.GetPropertyModifierY(j,ny);
         this.SetCoordYToDependentObj(dep,prop_from,modifier_from,ny);
        }
     }
//--- Save the current properties of the dependent graphical object as the previous ones
   dep.PropertiesCopyToPrevData();
//--- Move the management control point to new coordinates
   this.ExtToolkit.SetBaseObjTimePrice(this.Time(modifier),this.Price(modifier),modifier);
   this.ExtToolkit.SetBaseObjCoordXY(this.XDistance(),this.YDistance());
//--- Redraw the chart, if the flag is enabled
   if(redraw)
      ::ChartRedraw(m_chart_id);
//--- If all is successful, return 'true'
   return true;
  }
//+------------------------------------------------------------------+

The method is accompanied by detailed comments. In short, we first change the coordinates of the specified pivot point of the current object. If the object has dependent graphical objects bound to it, they should be moved to the new coordinates. This is exactly what happens in the method.

Remove handling mouse movements from the event handler as it is no longer needed:

//+------------------------------------------------------------------+
//| Event handler                                                    |
//+------------------------------------------------------------------+
void CGStdGraphObj::OnChartEvent(const int id,const long &lparam,const double &dparam,const string &sparam)
  {
   if(GraphElementType()!=GRAPH_ELEMENT_TYPE_STANDARD_EXTENDED)
      return;
   string name=this.Name();
   if(id==CHARTEVENT_CHART_CHANGE)
     {
      if(ExtToolkit==NULL)
         return;
      for(int i=0;i<this.Pivots();i++)
        {
         ExtToolkit.SetBaseObjTimePrice(this.Time(i),this.Price(i),i);
        }
      ExtToolkit.SetBaseObjCoordXY(this.XDistance(),this.YDistance());
      ExtToolkit.OnChartEvent(id,lparam,dparam,name);
     }
   if(id==CHARTEVENT_MOUSE_MOVE)
     {
      if(ExtToolkit!=NULL)
         ExtToolkit.OnChartEvent(id,lparam,dparam,name);
     }
  }
//+------------------------------------------------------------------+


Let's improve the collection class of graphical objects in \MQL5\Include\DoEasy\Collections\GraphElementsCollection.mqh.

When we move the cursor over the chart, while the chart features objects, the object the mouse cursor is hovering over is defined in the event handler. The handler of the mouse status relative to the object is then launched. When we hover the cursor over the object for handling pivot points of the extended standard graphical object, the form itself, as well as its index and the graphical object the form is attached to can be seen in the handler. In order not to look for this form and graphical object again outside the handler, we need to simply save the ID of the graphical object the form is attached to and the index of the form, above which the cursor is hovering, in the variables. This data allows us to quickly select the necessary objects from the lists and understand that the cursor is located above the form — by the value of these variables.

Insert these variables in the declaration of the method returning the pointer to the form located under the cursor:

//--- Return the pointer to the form located under the cursor
   CForm            *GetFormUnderCursor(const int id, 
                                        const long &lparam, 
                                        const double &dparam, 
                                        const string &sparam,
                                        ENUM_MOUSE_FORM_STATE &mouse_state,
                                        long &obj_ext_id,
                                        int &form_index);

The variables are to be passed to the method by a link. In other words, we will simply set the necessary values inside the method, and they will be saved in the appropriate variables for later use.

In the public section of the class, declare two methods returning the extended and standard graphical objects by ID:

//--- Return an (1) existing and (2) removed graphical object by chart name and ID
   CGStdGraphObj    *GetStdGraphObject(const string name,const long chart_id);
   CGStdGraphObj    *GetStdDelGraphObject(const string name,const long chart_id);
//--- Return the existing (1) extended and (2) standard graphical object by its ID
   CGStdGraphObj    *GetStdGraphObjectExt(const long id,const long chart_id);
   CGStdGraphObj    *GetStdGraphObject(const long id,const long chart_id);
//--- Return the list of (1) chart management objects and (2) removed graphical objects
   CArrayObj        *GetListChartsControl(void)                                                          { return &this.m_list_charts_control;  }
   CArrayObj        *GetListDeletedObj(void)                                                             { return &this.m_list_deleted_obj;     }

We need these methods to receive the pointer to the graphical object by its ID. Let's have a look at the implementation of these methods.

The method returning the existing extended standard graphical object by its ID:

//+------------------------------------------------------------------+
//| Return the existing extended standard                            |
//| graphical object by its ID                                       |
//+------------------------------------------------------------------+
CGStdGraphObj *CGraphElementsCollection::GetStdGraphObjectExt(const long id,const long chart_id)
  {
   CArrayObj *list=this.GetListStdGraphObjectExt();
   list=CSelect::ByGraphicStdObjectProperty(list,GRAPH_OBJ_PROP_CHART_ID,0,chart_id,EQUAL);
   list=CSelect::ByGraphicStdObjectProperty(list,GRAPH_OBJ_PROP_ID,0,id,EQUAL);
   return(list!=NULL && list.Total()>0 ? list.At(0) : NULL);
  }
//+------------------------------------------------------------------+

Here we receive the list of extended standard graphical objects. Only objects with the specified chart ID remain in the list.
From the obtained list, select an object with the specified object ID. If the obtained list is valid and not empty, return the pointer to the necessary object contained in the list. Otherwise, return NULL.

The method returning the existing standard graphical object by its ID:

//+------------------------------------------------------------------+
//| Return the existing standard                                     |
//| graphical object by its ID                                       |
//+------------------------------------------------------------------+
CGStdGraphObj *CGraphElementsCollection::GetStdGraphObject(const long id,const long chart_id)
  {
   CArrayObj *list=this.GetList(GRAPH_OBJ_PROP_CHART_ID,0,chart_id);
   list=CSelect::ByGraphicStdObjectProperty(list,GRAPH_OBJ_PROP_ID,0,id,EQUAL);
   return(list!=NULL && list.Total()>0 ? list.At(0) : NULL);
  }
//+------------------------------------------------------------------+

Here we receive the list of graphical objects by chart ID. In the obtained list, leave the object with the specified object ID.
If the obtained list is valid and not empty, return the pointer to the necessary object contained in the list
. Otherwise, return NULL.

Let's improve the method returning the pointer to the form located under the cursor. We need to add and initialize two new variables for storing the ID of the extended standard graphical object and the index of the anchor point the form handles, as well as to insert the block for handling extended standard graphical objects the search for forms, which are attached to these objects (and the mouse cursor is hovering over):

//+------------------------------------------------------------------+
//| Return the pointer to the form located under the cursor          |
//+------------------------------------------------------------------+
CForm *CGraphElementsCollection::GetFormUnderCursor(const int id, 
                                                    const long &lparam, 
                                                    const double &dparam, 
                                                    const string &sparam,
                                                    ENUM_MOUSE_FORM_STATE &mouse_state,
                                                    long &obj_ext_id,
                                                    int &form_index)
  {
//--- Set the ID of the extended standard graphical object to -1 
//--- and the index of the anchor point managed by the form to -1
   obj_ext_id=WRONG_VALUE;
   form_index=WRONG_VALUE;
//--- Initialize the mouse status relative to the form
   mouse_state=MOUSE_FORM_STATE_NONE;
//--- Declare the pointers to graphical element collection class objects
   CGCnvElement *elm=NULL;
   CForm *form=NULL;
//--- Get the list of objects the interaction flag is set for (there should be only one object)
   CArrayObj *list=CSelect::ByGraphCanvElementProperty(GetListCanvElm(),CANV_ELEMENT_PROP_INTERACTION,true,EQUAL);
//--- If managed to obtain the list and it is not empty
   if(list!=NULL && list.Total()>0)
     {
      //--- Get the only graphical element there
      elm=list.At(0);
      //--- If the element is a form object
      if(elm.TypeGraphElement()==GRAPH_ELEMENT_TYPE_FORM)
        {
         //--- Assign the pointer to the element for the form object pointer
         form=elm;
         //--- Get the mouse status relative to the form
         mouse_state=form.MouseFormState(id,lparam,dparam,sparam);
         //--- If the cursor is within the form, return the pointer to the form
         if(mouse_state>MOUSE_FORM_STATE_OUTSIDE_FORM_WHEEL)
            return form;
        }
     }
//--- If there is no a single form object with a specified interaction flag,
//--- in the loop by all graphical element collection class objects
   int total=this.m_list_all_canv_elm_obj.Total();
   for(int i=0;i<total;i++)
     {
      //--- get the next element
      elm=this.m_list_all_canv_elm_obj.At(i);
      if(elm==NULL)
         continue;
      //--- if the obtained element is a form object
      if(elm.TypeGraphElement()==GRAPH_ELEMENT_TYPE_FORM)
        {
         //--- Assign the pointer to the element for the form object pointer
         form=elm;
         //--- Get the mouse status relative to the form
         mouse_state=form.MouseFormState(id,lparam,dparam,sparam);
         //--- If the cursor is within the form, return the pointer to the form
         if(mouse_state>MOUSE_FORM_STATE_OUTSIDE_FORM_WHEEL)
            return form;
        }
     }
//--- If there is no a single form object from the collection list
//--- Get the list of extended standard graphical objects
   list=this.GetListStdGraphObjectExt();
   if(list!=NULL)
     {
      //--- in the loop by all extended standard graphical objects
      for(int i=0;i<list.Total();i++)
        {
         //--- get the next graphical object,
         CGStdGraphObj *obj_ext=list.At(i);
         if(obj_ext==NULL)
            continue;
         //--- get the object of its toolkit,
         CGStdGraphObjExtToolkit *toolkit=obj_ext.GetExtToolkit();
         if(toolkit==NULL)
            continue;
         //--- handle the event of changing the chart for the current graphical object
         obj_ext.OnChartEvent(CHARTEVENT_CHART_CHANGE,lparam,dparam,sparam);
         //--- Get the total number of form objects created for the current graphical object
         total=toolkit.GetNumControlPointForms();
         //--- In the loop by all form objects
         for(int j=0;j<total;j++)
           {
            //--- get the next form object,
            form=toolkit.GetControlPointForm(j);
            if(form==NULL)
               continue;
            //--- get the mouse status relative to the form
            mouse_state=form.MouseFormState(id,lparam,dparam,sparam);
            //--- If the cursor is inside the form,
            if(mouse_state>MOUSE_FORM_STATE_OUTSIDE_FORM_WHEEL)
              {
               //--- set the object ID and form index
               //--- and return the pointer to the form
               obj_ext_id=obj_ext.ObjectID();
               form_index=j;
               return form;
              }
           }
        }
     }
//--- Nothing is found - return NULL
   return NULL;
  }
//+------------------------------------------------------------------+

The entire logic of the added code block is described in the comments. In brief, we need to find a form object the mouse cursor is hovering over. First, we are looking for form objects stored in the list of collection class graphical elements. If not a single form is found, we should pass along all extended standard graphical objects while searching for their forms — the cursor can be over one of them. If this is the case, the ID of the extended standard graphical object the form is attached to is set in the variables passed to the method by the link. The form index is set as well so that we are able to know the pivot point and the graphical object managed by the form.

Now we should handle the interaction of the mouse cursor with form objects of extended standard graphical objects in the event handler. In addition, let's implement control over relocation of form objects so that they cannot enter the chart area in its upper right corner where the one-click trading mode activation button is located. This button always remains on top of all objects, so the relocated form should not enter its area to avoid accidental button clicks. If the one-click panel is already activated, the form should not enter its area as well since it may cause inconvenience when handling the form.

Let's have a look at the improvements and changes in the event handler:

//+------------------------------------------------------------------+
//| Event handler                                                    |
//+------------------------------------------------------------------+
void CGraphElementsCollection::OnChartEvent(const int id, const long &lparam, const double &dparam, const string &sparam)
  {
   CGStdGraphObj *obj_std=NULL;  // Pointer to the standard graphical object
   CGCnvElement  *obj_cnv=NULL;  // Pointer to the graphical element object on canvas
   ushort idx=ushort(id-CHARTEVENT_CUSTOM);
   if(id==CHARTEVENT_OBJECT_CHANGE  || id==CHARTEVENT_OBJECT_DRAG    || id==CHARTEVENT_OBJECT_CLICK   ||
      idx==CHARTEVENT_OBJECT_CHANGE || idx==CHARTEVENT_OBJECT_DRAG   || idx==CHARTEVENT_OBJECT_CLICK)
     {
      //--- Calculate the chart ID
      //--- If the event ID corresponds to an event from the current chart, the chart ID is received from ChartID
      //--- If the event ID corresponds to a user event, the chart ID is received from lparam
      //--- Otherwise, the chart ID is assigned to -1
      long param=(id==CHARTEVENT_OBJECT_CLICK ? ::ChartID() : idx==CHARTEVENT_OBJECT_CLICK ? lparam : WRONG_VALUE);
      long chart_id=(param==WRONG_VALUE ? (lparam==0 ? ::ChartID() : lparam) : param);
      //--- Get the object, whose properties were changed or which was relocated,
      //--- from the collection list by its name set in sparam
      obj_std=this.GetStdGraphObject(sparam,chart_id);
      //--- If failed to get the object by its name, it is not on the list,
      //--- which means its name has been changed
      if(obj_std==NULL)
        {
         //--- Let's search the list for the object that is not on the chart
         obj_std=this.FindMissingObj(chart_id);
         //--- If failed to find the object here as well, exit
         if(obj_std==NULL)
            return;
         //--- Get the name of the renamed graphical object on the chart, which is not in the collection list
         string name_new=this.FindExtraObj(chart_id);
         //--- set a new name for the collection list object, which does not correspond to any graphical object on the chart,
         //--- and send an event with the new name of the object to the control program chart
         if(obj_std.SetNamePrev(obj_std.Name()) && obj_std.SetName(name_new))
            ::EventChartCustom(this.m_chart_id_main,GRAPH_OBJ_EVENT_RENAME,obj_std.ChartID(),obj_std.TimeCreate(),obj_std.Name());
        }
      //--- Update the properties of the obtained object
      //--- and check their change
      obj_std.PropertiesRefresh();
      obj_std.PropertiesCheckChanged();
     }

//--- Handle standard graphical object events in the collection list
   for(int i=0;i<this.m_list_all_graph_obj.Total();i++)
     {
      //--- Get the next graphical object and
      obj_std=this.m_list_all_graph_obj.At(i);
      if(obj_std==NULL)
         continue;
      //--- call its event handler
      obj_std.OnChartEvent((id<CHARTEVENT_CUSTOM ? id : idx),lparam,dparam,sparam);
     }

//--- Handle chart changes for extended standard objects
   if(id==CHARTEVENT_CHART_CHANGE || idx==CHARTEVENT_CHART_CHANGE)
     {
      CArrayObj *list=this.GetListStdGraphObjectExt();
      if(list!=NULL)
        {
         for(int i=0;i<list.Total();i++)
           {
            obj_std=list.At(i);
            if(obj_std==NULL)
               continue;
            obj_std.OnChartEvent(CHARTEVENT_CHART_CHANGE,lparam,dparam,sparam);
           }
        }
     }
//--- Handling mouse events of graphical objects on canvas
//--- If the event is not a chart change
   else
     {
      //--- Check whether the mouse button is pressed
      bool pressed=(this.m_mouse.ButtonKeyState(id,lparam,dparam,sparam)==MOUSE_BUTT_KEY_STATE_LEFT ? true : false);
      ENUM_MOUSE_FORM_STATE mouse_state=MOUSE_FORM_STATE_NONE;
      //--- Declare static variables for the active form and status flags
      static CForm *form=NULL;
      static bool pressed_chart=false;
      static bool pressed_form=false;
      static bool move=false;
      //--- Declare static variables for the form index of managing an extended standard graphical object and its ID
      static int  form_index=WRONG_VALUE;
      static long graph_obj_id=WRONG_VALUE;
      
      //--- If the button is not pressed on the chart and the movement flag is not set, get the form, above which the cursor is located
      if(!pressed_chart && !move)
         form=this.GetFormUnderCursor(id,lparam,dparam,sparam,mouse_state,graph_obj_id,form_index);
      
      //--- If the button is not pressed, reset all flags and enable the chart tools 
      if(!pressed)
        {
         pressed_chart=false;
         pressed_form=false;
         move=false;
         this.SetChartTools(::ChartID(),true);
        }
      
      //--- If this is a mouse movement event and the movement flag is active, move the form, above which the cursor is located (if the pointer to it is valid)
      if(id==CHARTEVENT_MOUSE_MOVE && move)
        {
         if(form!=NULL)
           {
            //--- calculate the cursor movement relative to the form coordinate origin
            int x=this.m_mouse.CoordX()-form.OffsetX();
            int y=this.m_mouse.CoordY()-form.OffsetY();
            //--- get the width and height of the chart the form is located at
            int chart_width=(int)::ChartGetInteger(form.ChartID(),CHART_WIDTH_IN_PIXELS,form.SubWindow());
            int chart_height=(int)::ChartGetInteger(form.ChartID(),CHART_HEIGHT_IN_PIXELS,form.SubWindow());
            //--- If the form is outside the extended standard graphical object
            if(form_index==WRONG_VALUE)
              {
               //--- Adjust the calculated form coordinates if the form is out of the chart range
               if(x<0) x=0;
               if(x>chart_width-form.Width()) x=chart_width-form.Width();
               if(y<0) y=0;
               if(y>chart_height-form.Height()) y=chart_height-form.Height();
               //--- If the chart has no one-click trading panel,
               if(!::ChartGetInteger(form.ChartID(),CHART_SHOW_ONE_CLICK))
                 {
                  //--- calculate the form coordinate so that the form does not enter the one-click trading button during relocation
                  if(y<17 && x<41)
                     y=17;
                 }
               //--- If the chart has the one-click trading panel enabled,
               else
                 {
                  //--- calculate the form coordinate so that the form does not enter the one-click trading panel area during relocation
                  if(y<80 && x<192)
                     y=80;
                 }
              }
            //--- If the form is included into the extended standard graphical object
            else
              {
               if(graph_obj_id>WRONG_VALUE)
                 {
                  //--- Get the list of objects by the object ID (there should be one object)
                  CArrayObj *list_ext=CSelect::ByGraphicStdObjectProperty(GetListStdGraphObjectExt(),GRAPH_OBJ_PROP_ID,0,graph_obj_id,EQUAL);
                  //--- If managed to obtain the list and it is not empty,
                  if(list_ext!=NULL && list_ext.Total()>0)
                    {
                     //--- get the graphical object from the list
                     CGStdGraphObj *ext=list_ext.At(0);
                     //--- If the pointer to the object is received,
                     if(ext!=NULL)
                       {
                        //--- get the object type
                        ENUM_OBJECT type=ext.GraphObjectType();
                        //--- If the object is constructed based on screen coordinates, set the coordinates to the object
                        if(type==OBJ_LABEL || type==OBJ_BUTTON || type==OBJ_BITMAP_LABEL || type==OBJ_EDIT || type==OBJ_RECTANGLE_LABEL)
                          {
                           ext.SetXDistance(x);
                           ext.SetYDistance(y);
                          }
                        //--- otherwise, if the object is based on time/price coordinates
                        else
                          {
                           //--- calculate the coordinate shift and limit the coordinates so that they are not out of the chart range
                           int shift=(int)::ceil(form.Width()/2)+1;
                           if(x+shift<0)
                              x=-shift;
                           if(x+shift>chart_width)
                              x=chart_width-shift;
                           if(y+shift<0)
                              y=-shift;
                           if(y+shift>chart_height)
                              y=chart_height-shift;
                           //--- set calculated coordinates in the object
                           ext.ChangeCoordsExtendedObj(x+shift,y+shift,form_index);
                          }
                       }
                    }
                 }
              }
            //--- Move the form by the obtained coordinates
            form.Move(x,y,true);
           }
        }
   
      //--- Display debugging comments on the chart
      Comment
        (
         (form!=NULL ? form.Name()+":" : ""),"\n",
         EnumToString((ENUM_CHART_EVENT)id),"\n",
         EnumToString(this.m_mouse.ButtonKeyState(id,lparam,dparam,sparam)),
         "\n",EnumToString(mouse_state),
         "\npressed=",pressed,", move=",move,(form!=NULL ? ", Interaction="+(string)form.Interaction() : ""),
         "\npressed_chart=",pressed_chart,", pressed_form=",pressed_form,
         "\nform_index=",form_index,", graph_obj_id=",graph_obj_id
        );
      
      //--- If the cursor is not above the form
      if(form==NULL)
        {
         //--- If the mouse button is pressed
         if(pressed)
           {
            //--- If the button is still pressed and held on the form, exit
            if(pressed_form)
              {
               return;
              }
            //--- If the button hold flag is not enabled yet, set the flags and enable chart tools
            if(!pressed_chart)
              {
               pressed_chart=true;  // Button is held on the chart
               pressed_form=false;  // Cursor is not above the form
               move=false;          // movement disabled
               this.SetChartTools(::ChartID(),true);
              }
           }
         //--- If the mouse button is not pressed
         else
           {
            //--- Get the list of extended standard graphical objects
            CArrayObj *list_ext=GetListStdGraphObjectExt();
            //--- In the loop by all extended graphical objects,
            int total=list_ext.Total();
            for(int i=0;i<total;i++)
              {
               //--- get the next graphical object
               CGStdGraphObj *obj=list_ext.At(i);
               if(obj==NULL)
                  continue;
               //--- and redraw it without a point and a circle
               obj.RedrawControlPointForms(0,CTRL_POINT_COLOR);
              }
           }
        }
      //--- If the cursor is above the form
      else
        {
         //--- If the button is still pressed and held on the chart, exit
         if(pressed_chart)
           {
            return;
           }
         
         //--- If the flag of holding the button on the form is not set yet
         if(!pressed_form)
           {
            pressed_chart=false;    // The button is not pressed on the chart
            this.SetChartTools(::ChartID(),false);
            
            //--- 'The cursor is inside the form, no mouse buttons are clicked' event handler
            if(mouse_state==MOUSE_FORM_STATE_INSIDE_FORM_NOT_PRESSED)
              {
               //--- If the cursor is above the extended graphical object pivot point control form,
               if(graph_obj_id>WRONG_VALUE)
                 {
                  //--- get the object by the object and chart IDs
                  CGStdGraphObj *graph_obj=this.GetStdGraphObjectExt(graph_obj_id,form.ChartID());
                  if(graph_obj!=NULL)
                    {
                     //--- Get the toolkit of the extended standard graphical object
                     CGStdGraphObjExtToolkit *toolkit=graph_obj.GetExtToolkit();
                     if(toolkit!=NULL)
                       {
                        //--- Draw a circle with a point on the form
                        toolkit.DrawControlPoint(form,255,CTRL_POINT_COLOR);
                       }
                    }
                 }
              }
            //--- 'The cursor is inside the form, a mouse button is clicked (any)' event handler
            if(mouse_state==MOUSE_FORM_STATE_INSIDE_FORM_PRESSED)
              {
               this.SetChartTools(::ChartID(),false);
               //--- If the flag of holding the form is not set yet
               if(!pressed_form)
                 {
                  pressed_form=true;      // set the flag of pressing on the form
                  pressed_chart=false;    // remove the flag of pressing on the chart
                 }
              }
            //--- 'The cursor is inside the form, the mouse wheel is being scrolled' event handler workpiece
            if(mouse_state==MOUSE_FORM_STATE_INSIDE_FORM_WHEEL)
              {
               
              }
            
            
            //--- 'The cursor is inside the active area, the mouse buttons are not clicked' event handler
            if(mouse_state==MOUSE_FORM_STATE_INSIDE_ACTIVE_AREA_NOT_PRESSED)
              {
               //--- Set the cursor shift relative to the form initial coordinates
               form.SetOffsetX(this.m_mouse.CoordX()-form.CoordX());
               form.SetOffsetY(this.m_mouse.CoordY()-form.CoordY());
               //--- If the cursor is above the active area of the extended graphical object pivot point control form
               if(graph_obj_id>WRONG_VALUE)
                 {
                  //--- get the object by the object and chart IDs
                  CGStdGraphObj *graph_obj=this.GetStdGraphObjectExt(graph_obj_id,form.ChartID());
                  if(graph_obj!=NULL)
                    {
                     //--- Get the toolkit of the extended standard graphical object
                     CGStdGraphObjExtToolkit *toolkit=graph_obj.GetExtToolkit();
                     if(toolkit!=NULL)
                       {
                        //--- Draw a circle with a point on the form
                        toolkit.DrawControlPoint(form,255,CTRL_POINT_COLOR);
                       }
                    }
                 }
              }
            //--- 'The cursor is inside the active area,  any mouse button is clicked' event handler
            if(mouse_state==MOUSE_FORM_STATE_INSIDE_ACTIVE_AREA_PRESSED && !move)
              {
               pressed_form=true;   // the flag of holding the mouse button on the form
               //--- If the left mouse button is pressed
               if(this.m_mouse.IsPressedButtonLeft())
                 {
                  //--- Set flags and form parameters
                  move=true;                                            // movement flag
                  form.SetInteraction(true);                            // flag of the form interaction with the environment
                  form.BringToTop();                                    // form on the background - above all others
                  this.ResetAllInteractionExeptOne(form);               // Reset interaction flags for all forms except the current one
                  form.SetOffsetX(this.m_mouse.CoordX()-form.CoordX()); // Cursor shift relative to the X coordinate
                  form.SetOffsetY(this.m_mouse.CoordY()-form.CoordY()); // Cursor shift relative to the Y coordinate
                 }
              }
            //--- 'The cursor is inside the active area, the mouse wheel is being scrolled' event handler workpiece
            if(mouse_state==MOUSE_FORM_STATE_INSIDE_ACTIVE_AREA_WHEEL)
              {
               
              }
            
            
            //--- 'The cursor is inside the window scrolling area, no mouse buttons are clicked' event handler workpiece
            if(mouse_state==MOUSE_FORM_STATE_INSIDE_SCROLL_AREA_NOT_PRESSED)
              {
               
              }
            //--- 'The cursor is inside the window scrolling area, a mouse button is clicked (any)' event handler workpiece
            if(mouse_state==MOUSE_FORM_STATE_INSIDE_SCROLL_AREA_PRESSED)
              {
               
              }
            //--- 'The cursor is inside the window scrolling area, the mouse wheel is being scrolled' event handler workpiece
            if(mouse_state==MOUSE_FORM_STATE_INSIDE_SCROLL_AREA_WHEEL)
              {
               
              }
           }
        }
     }
  }
//+------------------------------------------------------------------+

All improvements in the method are accompanied by detailed comments in the code. If you have any questions, feel free to ask them in the comments below.

These are all the improvements I was going to make today.


Test

To perform the test, let's use the EA from the previous article and save it to \MQL5\Experts\TestDoEasy\Part98\ as TestDoEasyPart98.mq5.

The only change to be implemented is the creation of three form objects:

//+------------------------------------------------------------------+
//|                                             TestDoEasyPart98.mq5 |
//|                                  Copyright 2021, MetaQuotes Ltd. |
//|                             https://mql5.com/en/users/artmedia70 |
//+------------------------------------------------------------------+
#property copyright "Copyright 2021, MetaQuotes Ltd."
#property link      "https://mql5.com/en/users/artmedia70"
#property version   "1.00"
//--- includes
#include <DoEasy\Engine.mqh>
//--- defines
#define        FORMS_TOTAL (3)   // Number of created forms
#define        START_X     (4)   // Initial X coordinate of the shape
#define        START_Y     (4)   // Initial Y coordinate of the shape
#define KEY_LEFT           (188) // Left
#define KEY_RIGHT          (190) // Right
#define KEY_ORIGIN         (191) // Initial properties
//--- input parameters
sinput   bool              InpMovable     =  true;          // Movable forms flag
sinput   ENUM_INPUT_YES_NO InpUseColorBG  =  INPUT_YES;     // Use chart background color to calculate shadow color
sinput   color             InpColorForm3  =  clrCadetBlue;  // Third form shadow color (if not background color) 
//--- global variables
CEngine        engine;
color          array_clr[];
//+------------------------------------------------------------------+

In this regard, let's slightly adjust the calculation of coordinates of each created form.
Form object declaration is set outside the loop
.
The first form is to be constructed on the Y coordinate of 100, while the remaining ones — with the indent of 20 pixels from the bottom edge of the previous form:

//+------------------------------------------------------------------+
//| Expert initialization function                                   |
//+------------------------------------------------------------------+
int OnInit()
  {
//--- Set EA global variables
   ArrayResize(array_clr,2);        // Array of gradient filling colors
   array_clr[0]=C'26,100,128';      // Original ≈Dark-azure color
   array_clr[1]=C'35,133,169';      // Lightened original color
//--- Create the array with the current symbol and set it to be used in the library
   string array[1]={Symbol()};
   engine.SetUsedSymbols(array);
   //--- Create the timeseries object for the current symbol and period, and show its description in the journal
   engine.SeriesCreate(Symbol(),Period());
   engine.GetTimeSeriesCollection().PrintShort(false); // Short descriptions
//--- Create form objects
   CForm *form=NULL;
   for(int i=0;i<FORMS_TOTAL;i++)
     {
      //--- When creating an object, pass all the required parameters to it
      form=new CForm("Form_0"+string(i+1),30,(form==NULL ? 100 : form.BottomEdge()+20),100,30);
      if(form==NULL)
         continue;
      //--- Set activity and moveability flags for the form
      form.SetActive(true);
      form.SetMovable(true);
      //--- Set the form ID and the index in the list of objects
      form.SetID(i);
      form.SetNumber(0);   // (0 - main form object) Auxiliary objects may be attached to the main one. The main object is able to manage them
      //--- Set the opacity of 200
      form.SetOpacity(245);
      //--- The form background color is set as the first color from the color array
      form.SetColorBackground(array_clr[0]);
      //--- Form outlining frame color
      form.SetColorFrame(clrDarkBlue);
      //--- Draw the shadow drawing flag
      form.SetShadow(false);
      //--- Calculate the shadow color as the chart background color converted to the monochrome one
      color clrS=form.ChangeColorSaturation(form.ColorBackground(),-100);
      //--- If the settings specify the usage of the chart background color, replace the monochrome color with 20 units
      //--- Otherwise, use the color specified in the settings for drawing the shadow
      color clr=(InpUseColorBG ? form.ChangeColorLightness(clrS,-20) : InpColorForm3);
      //--- Draw the form shadow with the right-downwards offset from the form by three pixels along all axes
      //--- Set the shadow opacity to 200, while the blur radius is equal to 4
      form.DrawShadow(3,3,clr,200,4);
      //--- Fill the form background with a vertical gradient
      form.Erase(array_clr,form.Opacity(),true);
      //--- Draw an outlining rectangle at the edges of the form
      form.DrawRectangle(0,0,form.Width()-1,form.Height()-1,form.ColorFrame(),form.Opacity());
      form.Done();
      
      //--- Display the text describing the gradient type and update the form
      //--- Text parameters: the text coordinates and the anchor point in the form center
      //--- Create a new text animation frame with the ID of 0 and display the text on the form
      form.TextOnBG(0,TextByLanguage("Тест 0","Test 0")+string(i+1),form.Width()/2,form.Height()/2,FRAME_ANCHOR_CENTER,C'211,233,149',255,true,true);
      //--- Add the form to the list
      if(!engine.GraphAddCanvElmToCollection(form))
         delete form;
     }
//---
   return(INIT_SUCCEEDED);
  }
//+------------------------------------------------------------------+

In the OnChartEvent() handler, shorten the length of the graphical object name created by mouse clicks (the previous one was "TrendLineExt") to avoid exceeding 63 characters when creating a graphical resource:

   if(id==CHARTEVENT_CLICK)
     {
      if(!IsCtrlKeyPressed())
         return;
      //--- Get the chart click coordinates
      datetime time=0;
      double price=0;
      int sw=0;
      if(ChartXYToTimePrice(ChartID(),(int)lparam,(int)dparam,sw,time,price))
        {
         //--- Get the right point coordinates for a trend line
         datetime time2=iTime(Symbol(),PERIOD_CURRENT,1);
         double price2=iOpen(Symbol(),PERIOD_CURRENT,1);
         
         //--- Create the "Trend line" object
         string name_base="TLineExt";
         engine.CreateLineTrend(name_base,0,true,time,price,time2,price2);
         //--- Get the object from the list of graphical objects by chart name and ID
         CGStdGraphObj *obj=engine.GraphGetStdGraphObjectExt(name_base,ChartID());
         
         //--- Create the "Left price label" object
         string name_dep="PriceLeftExt";
         engine.CreatePriceLabelLeft(name_dep,0,false,time,price);
         //--- Get the object from the list of graphical objects by chart name and ID and
         CGStdGraphObj *dep=engine.GraphGetStdGraphObject(name_dep,ChartID());
         //--- add it to the list of graphical objects bound to the "Trend line" object
         obj.AddDependentObj(dep);
         //--- Set its pivot point by X and Y axis to the trend line left point
         dep.AddNewLinkedCoord(GRAPH_OBJ_PROP_TIME,0,GRAPH_OBJ_PROP_PRICE,0);
         
         //--- Create the "Right price label" object
         name_dep="PriceRightExt";
         engine.CreatePriceLabelRight(name_dep,0,false,time2,price2);
         //--- Get the object from the list of graphical objects by chart name and ID and
         dep=engine.GraphGetStdGraphObject(name_dep,ChartID());
         //--- add it to the list of graphical objects bound to the "Trend line" object
         obj.AddDependentObj(dep);
         //--- Set its pivot point by X and Y axis to the trend line right point
         dep.AddNewLinkedCoord(GRAPH_OBJ_PROP_TIME,1,GRAPH_OBJ_PROP_PRICE,1);
        }
     }

//--- Handling graphical element collection events

Compile the EA and launch it on the chart:


As we can see, the form does not enter the area where the one-click trading panel button is located, as well as does not enter the panel area if it has been activated. The forms for handling pivot points of an extended standard graphical object work as intended and do not leave the chart limits.
However, there are drawbacks as well. After creating a composite graphical object and moving its pivot points, they are located above the form objects. In some cases, this may turn out to be incorrect. For example, if we have a panel, the line dragged by the cursor should pass under the panel rather than be drawn above it. If we click each of the forms one by one, they are set above the composite graphical object and it is not drawn above these forms during a relocation. If we partially overlay three forms on top of each other, then when we hover over the second form, the first one becomes active. I will fix this. Here we need to use the "depth" of all forms' location relative to each other and to other objects on the chart.


What's next?

In the next article, I will continue my work on composite graphical objects and their functionality.

All files of the current library version, test EA and chart event control indicator for MQL5 are attached below for you to test and download. Leave your questions, comments and suggestions in the comments.

Back to contents

*Previous articles within the series:

Graphics in DoEasy library (Part 93): Preparing functionality for creating composite graphical objects
Graphics in DoEasy library (Part 94): Moving and deleting composite graphical objects
Graphics in DoEasy library (Part 95): Composite graphical object controls
Graphics in DoEasy library (Part 96): Graphics in form objects and handling mouse events
Graphics in DoEasy library (Part 97): Independent handling of form object movement

Translated from Russian by MetaQuotes Ltd.
Original article: https://www.mql5.com/ru/articles/10521

Attached files |
MQL5.zip (4233.69 KB)
Multiple indicators on one chart (Part 04): Advancing to an Expert Advisor Multiple indicators on one chart (Part 04): Advancing to an Expert Advisor
In my previous articles, I have explained how to create an indicator with multiple subwindows, which becomes interesting when using custom indicators. This time we will see how to add multiple windows to an Expert Advisor.
Learn how to design a trading system by ATR Learn how to design a trading system by ATR
In this article, we will learn a new technical tool that can be used in trading, as a continuation within the series in which we learn how to design simple trading systems. This time we will work with another popular technical indicator: Average True Range (ATR).
Graphics in DoEasy library (Part 99): Moving an extended graphical object using a single control point Graphics in DoEasy library (Part 99): Moving an extended graphical object using a single control point
In the previous article, I implemented the ability to move pivot points of an extended graphical object using control forms. Now I am going to implement the ability to move a composite graphical object using a single graphical object control point (form).
Tips from a professional programmer (Part III): Logging. Connecting to the Seq log collection and analysis system Tips from a professional programmer (Part III): Logging. Connecting to the Seq log collection and analysis system
Implementation of the Logger class for unifying and structuring messages which are printed to the Experts log. Connection to the Seq log collection and analysis system. Monitoring log messages online.