How to update the text of an Edit chart object with each tick?

[rdone]

Hi,

This adaptation of the Edit example code populates the Edit text with the spread when the EA loads, but I need it to update the text with the current spread with each tick. I found solutions using the old object oriented approach but not the new object oriented approach. I tried updating using:

EVENT_MAP_BEGIN(CControlsDialog)

   ON_EVENT(ON_CHANGE,Spread,OnChangeEdit)

EVENT_MAP_END(CAppDialog)

and within OnTick() and OnSetText() but couldn't get anything to work. Does anyone have or know of some code that will or can be made to work for this task? Thanks in advance.

//+------------------------------------------------------------------+
//|                                                 ControlsEdit.mq5 |
//|                        Copyright 2017, MetaQuotes Software Corp. |
//|                                             https://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "Copyright 2017, MetaQuotes Software Corp."
#property link      "https://www.mql5.com"
#property version   "1.00"
#property description "Control Panels and Dialogs. Demonstration class CEdit"
#include <Controls\Dialog.mqh>
#include <Controls\Edit.mqh>
//+------------------------------------------------------------------+
//| defines                                                          |
//+------------------------------------------------------------------+
//--- indents and gaps
#define INDENT_LEFT                         (11)      // indent from left (with allowance for border width)
#define INDENT_TOP                          (11)      // indent from top (with allowance for border width)
#define INDENT_RIGHT                        (11)      // indent from right (with allowance for border width)
#define INDENT_BOTTOM                       (11)      // indent from bottom (with allowance for border width)
#define CONTROLS_GAP_X                      (5)       // gap by X coordinate
#define CONTROLS_GAP_Y                      (5)       // gap by Y coordinate
//--- for buttons
#define BUTTON_WIDTH                        (100)     // size by X coordinate
#define BUTTON_HEIGHT                       (20)      // size by Y coordinate
//--- for the indication area
#define EDIT_HEIGHT                         (20)      // size by Y coordinate
//--- for group controls
#define GROUP_WIDTH                         (150)     // size by X coordinate
#define LIST_HEIGHT                         (179)     // size by Y coordinate
#define RADIO_HEIGHT                        (56)      // size by Y coordinate
#define CHECK_HEIGHT                        (93)      // size by Y coordinate
//+------------------------------------------------------------------+
//| Class CControlsDialog                                            |
//| Usage: main dialog of the Controls application                   |
//+------------------------------------------------------------------+
class CControlsDialog : public CAppDialog
  {
private:
   CEdit             m_edit;                          // CEdit object
 
public:
                     CControlsDialog(void);
                    ~CControlsDialog(void);
   //--- create
   virtual bool      Create(const long chart,const string name,const int subwin,const int x1,const int y1,const int x2,const int y2);
   //--- chart event handler
 
protected:
   //--- create dependent controls
   bool              CreateEdit(void);
  };
//+------------------------------------------------------------------+
//| Constructor                                                      |
//+------------------------------------------------------------------+
CControlsDialog::CControlsDialog(void)
  {
  }
//+------------------------------------------------------------------+
//| Destructor                                                       |
//+------------------------------------------------------------------+
CControlsDialog::~CControlsDialog(void)
  {
  }
//+------------------------------------------------------------------+
//| Create                                                           |
//+------------------------------------------------------------------+
bool CControlsDialog::Create(const long chart,const string name,const int subwin,const int x1,const int y1,const int x2,const int y2)
  {
   if(!CAppDialog::Create(chart,name,subwin,x1,y1,x2,y2))
      return(false);
//--- create dependent controls
   if(!CreateEdit())
      return(false);
//--- succeed
   return(true);
  }
//+------------------------------------------------------------------+
//| Create the display field                                         |
//+------------------------------------------------------------------+
bool CControlsDialog::CreateEdit(void)
  {
//--- coordinates
   int x1=INDENT_LEFT;
   int y1=INDENT_TOP;
   int x2=ClientAreaWidth()-INDENT_RIGHT;
   int y2=y1+EDIT_HEIGHT;
//--- create
   if(!m_edit.Create(m_chart_id,m_name+"Edit",m_subwin,x1,y1,x2,y2))
      return(false);
//--- allow editing the content
   if(!m_edit.Text(DoubleToString(Spread, Digits)))
      return(false);
   if(!m_edit.ReadOnly(true))
      return(false);
   if(!Add(m_edit))
      return(false);
//--- succeed
   return(true);
  }
//+------------------------------------------------------------------+
//| Global Variables                                                 |
//+------------------------------------------------------------------+
CControlsDialog ExtDialog;
double Spread = Ask - Bid;
//+------------------------------------------------------------------+
//| Expert initialization function                                   |
//+------------------------------------------------------------------+
int OnInit()
  {
//--- create application dialog
   if(!ExtDialog.Create(0,"Controls",0,40,40,380,344))
      return(INIT_FAILED);
//--- run application
   ExtDialog.Run();
//--- succeed
   return(INIT_SUCCEEDED);
  }
//+------------------------------------------------------------------+
//| Expert deinitialization function                                 |
//+------------------------------------------------------------------+
void OnDeinit(const int reason)
  {
//--- clear comments
   Comment("");
//--- destroy dialog
   ExtDialog.Destroy(reason);
  }
//+------------------------------------------------------------------+
//| Expert chart event function                                      |
//+------------------------------------------------------------------+
void OnChartEvent(const int id,         // event ID  
                  const long& lparam,   // event parameter of the long type
                  const double& dparam, // event parameter of the double type
                  const string& sparam) // event parameter of the string type
  {
   ExtDialog.ChartEvent(id,lparam,dparam,sparam);
  }

[Seng Joo Thio]

rdone:

Hi,

This adaptation of the Edit example code populates the Edit text with the spread when the EA loads, but I need it to update the text with the current spread with each tick. I found solutions using the old object oriented approach but not the new object oriented approach. I tried updating using:

EVENT_MAP_BEGIN(CControlsDialog)

   ON_EVENT(ON_CHANGE,Spread,OnChangeEdit)

EVENT_MAP_END(CAppDialog)

and within OnTick() and OnSetText() but couldn't get anything to work. Does anyone have or know of some code that will or can be made to work for this task? Thanks in advance.

What I did was to create a function within the CControlsDialog class, e.g. UpdateSpread(double newSpread), which contains the line m_edit.Text(string(newSpread)); for example... and I'll just call that function from my OnTick()/OnCalculate() whenever necessary.

[rdone]

Seng Joo Thio: Thanks for teaching me how to catch this kind of fish. I will be able to eat for a while now. I took a more generalized approach so that the code is not specific to Spread and could be used in other contexts. The attached code seems to be working, but let me know if there is a better way.

[pltorrent]

@rdone

In case of your example:

ObjectSetString(0,ExtDialog.Name()+"Edit",OBJPROP_TEXT, spread_value);

No functions needed ;)