How to populate spin edit with decimal numbers?

[rdone]

The example code at https://www.mql5.com/en/docs/standardlibrary/controls/cspinedit works fine for me (v.5.00 build 2302) but when I change the minimum, maximum, and current value parameters from 10, 100, and 50 to numbers with a decimal (e.g., 0.00001, 0.00010, and 0.00010, respectively), I get the "truncation of constant value" warning and the spin edit is created on the chart but not populated. Does the spin edit not work with decimal numbers, or how can I adapt the code so it will work with numbers with a fixed number of decimal places? I am new to the objected oriented approach and am trying to learn from example code but did not find this issue addressed anywhere. Thanks in advance.

//+------------------------------------------------------------------+
//|                                             ControlsSpinEdit.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 CSpinEdit"
#include <Controls\Dialog.mqh>
#include <Controls\SpinEdit.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:
   CSpinEdit         m_spin_edit;                     // CSpinEdit 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
   virtual bool      OnEvent(const int id,const long &lparam,const double &dparam,const string &sparam);
 
protected:
   //--- create dependent controls
   bool              CreateSpinEdit(void);
   //--- handlers of the dependent controls events
   void              OnChangeSpinEdit(void);
  };
//+------------------------------------------------------------------+
//| Event Handling                                                   |
//+------------------------------------------------------------------+
EVENT_MAP_BEGIN(CControlsDialog)
   ON_EVENT(ON_CHANGE,m_spin_edit,OnChangeSpinEdit)
EVENT_MAP_END(CAppDialog)
//+------------------------------------------------------------------+
//| 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(!CreateSpinEdit())
      return(false);
//--- succeed
   return(true);
  }
//+------------------------------------------------------------------+
//| Create the "SpinEdit" element                                    |
//+------------------------------------------------------------------+
bool CControlsDialog::CreateSpinEdit(void)
  {
//--- coordinates
   int x1=INDENT_LEFT;
   int y1=INDENT_TOP+(EDIT_HEIGHT+CONTROLS_GAP_Y)+(BUTTON_HEIGHT+CONTROLS_GAP_Y);
   int x2=x1+GROUP_WIDTH;
   int y2=y1+EDIT_HEIGHT;
//--- create
   if(!m_spin_edit.Create(m_chart_id,m_name+"SpinEdit",m_subwin,x1,y1,x2,y2))
      return(false);
   if(!Add(m_spin_edit))
      return(false);
   m_spin_edit.MinValue(10);
   m_spin_edit.MaxValue(100);
   m_spin_edit.Value(50);
   Comment(__FUNCTION__+" : Value="+IntegerToString(m_spin_edit.Value()));
//--- succeed
   return(true);
  }
//+------------------------------------------------------------------+
//| Event handler                                                    |
//+------------------------------------------------------------------+
void CControlsDialog::OnChangeSpinEdit(void)
  {
   Comment(__FUNCTION__+" : Value="+IntegerToString(m_spin_edit.Value()));
  }
//+------------------------------------------------------------------+
//| Global Variables                                                 |
//+------------------------------------------------------------------+
CControlsDialog ExtDialog;
//+------------------------------------------------------------------+
//| 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);
  }

[rdone]

The Questions for CAppDialog and CSpinEdit thread worked great for me. I had gone down the same path of adapting the SpinEdit.mgh file but hadn't quite figured it all out. Kudos to Roddo Greenwood et al. for getting that sorted.

[Frieder Kauber]

Hello,

late post, but how can I catch the click on the increment and decrement button in the example above?

Thank you

[amrali]

You can use "SpinEditDouble.mqh" from this link to handle decimal numbers.

https://www.mql5.com/en/code/28029