Hotkey programming to turn on/off the indicator

[toyogo00]

Hi,

I found this link on how to use hotkey programming.  I further use the hotkey to turn on/off the display of VLINE for US/UK session on hourly or below chart.  See code:

It works but 2 issues:

a.  After pressing Ctrl-J, I have to shift the screen using mouse in order to view the vLine.

b1.  I have to press Ctrl-J two times to display all 5 vLines.  The 1st Ctrl-J displays only sTime[0-3] and the next Ctrl-J displays sTime[4].

b2.  likewise, I also have to press Ctrl-Q two times to turn off the 5 vlines.

Pls advise!

Regards,

Toyogo

//+------------------------------------------------------------------+

//|                                            DisplaySession.mq5 |
//|                                              http://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "2014"
#property link      "http://www.mql5.com"

#property indicator_chart_window
#property indicator_buffers 2
#property indicator_plots   1
#define   TimeSession       5

//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+

static string name3[TimeSession];
static datetime sTime[TimeSession];

void OnInit() {
   datetime lTime = TimeCurrent();
   MqlDateTime ldate;
   TimeToStruct(lTime,ldate);

   name3[0] = "LNSessionStart";  // the server time is based on US close.  i.e. UTC+2
   name3[1] = "LNSessionEnd";
   name3[2] = "USSessionStart";
   name3[3] = "USSessionEnd";
   name3[4] = "MTSessionStart";
   sTime[0] = StringToTime(IntegerToString(ldate.year)+"."+IntegerToString(ldate.mon)+"."+IntegerToString(ldate.day)+" 10:00");  //LN start
   sTime[1] = StringToTime(IntegerToString(ldate.year)+"."+IntegerToString(ldate.mon)+"."+IntegerToString(ldate.day)+" 18:00");  //LN End 
   sTime[2] = StringToTime(IntegerToString(ldate.year)+"."+IntegerToString(ldate.mon)+"."+IntegerToString(ldate.day)+" 15:00");  //US start
   sTime[3] = StringToTime(IntegerToString(ldate.year)+"."+IntegerToString(ldate.mon)+"."+IntegerToString(ldate.day)+" 23:00");  //US End
   sTime[4] = StringToTime(IntegerToString(ldate.year)+"."+IntegerToString(ldate.mon)+"."+IntegerToString(ldate.day)+" 00:00");  //MT Start
}

void OnDeinit(const int reason) {
  int x;
  for (x=0; x<TimeSession; x++) {
    if (ObjectFind(0,name3[x]) != -1) ObjectDelete(0,name3[x]);
  }
}

static bool ctrl_pressed = false;

void OnChartEvent(const int id,
                  const long &lparam,
                  const double &dparam,
                  const string &sparam)
{
   int x;
   ENUM_TIMEFRAMES cTime;

   if (id == CHARTEVENT_KEYDOWN) {
      if (ctrl_pressed == false && lparam == 17)  // Ctrl key pressed
         ctrl_pressed = true;
      else if (ctrl_pressed == true) {
         if (lparam == 74) {         //Ctrl-J to activate DispSession
            cTime=Period(); 
            if (cTime == PERIOD_H1 || cTime == PERIOD_M30 || cTime == PERIOD_M15 || cTime == PERIOD_M5) {
               for (x=0; x<TimeSession; x++) {
                  if (ObjectFind(0,name3[x]) != -1) ObjectDelete(0,name3[x]);
                  ObjectCreate(0,name3[x],OBJ_VLINE,0,sTime[x],0);          
                  ObjectSetInteger(0,name3[x],OBJPROP_COLOR,Aqua);
                  ObjectSetInteger(0,name3[x],OBJPROP_STYLE,STYLE_DOT);
                  ObjectSetInteger(0,name3[x],OBJPROP_WIDTH,1);
                  ObjectSetInteger(0,name3[x],OBJPROP_RAY,false);
                  ObjectSetInteger(0,name3[x],OBJPROP_BACK,true);
               }
            }
            ctrl_pressed = false;
         } else if (lparam == 81) {  //Ctrl-Q to deactivate DispSession
            for (x=0; x<TimeSession; x++) {
               if (ObjectFind(0,name3[x]) != -1) ObjectDelete(0,name3[x]);
            }
            ctrl_pressed = false;
         }
      }
   }
}

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(rates_total);
}

[Alain Verleyen]

Next time, please use SRC button when you post code. I edited it for you.

From my experience CHARTEVENT_KEYDOWN isn't reliable to detect key combination inputs.

Your code works well if you press <Ctrl+J>, then release all, then press <Ctrl+Q>, then release all... But normal behavior (in any Windows program) like pressing <Ctrl> then <J>, releasing J key, then press <Q>, all of that keeping <Ctrl> pressed, doesn't work and can't be detected.

I already report this to ServiceDesk (#826140), but without success, their reply was :

You should analyze the value of the sparam for event CHARTEVENT_KEYDOWN as it said in MSDN (http://msdn.microsoft.com/en-us/library/983st27a%28v=vs.90%29.aspx)

Event	Value of the id parameter	Value of the lparam parameter	Value of the dparam parameter	Value of the sparam parameter
Event of a keystroke	CHARTEVENT_KEYDOWN	code of a pressed key	Repeat count (the number of times the keystroke is repeated as a result of the user holding down the key)	The string value of a bit mask describing the status of keyboard buttons

But I can't find a way to have it working well. So my opinion is that there is no reliable way to detect correctly combination of keys input. I would be happy if some can demonstrate that I am wrong.

[toyogo00]

angevoyageur:

Next time, please use SRC button when you post code. I edited it for you.

From my experience CHARTEVENT_KEYDOWN isn't reliable to detect key combination inputs.

Your code works well if you press <Ctrl+J>, then release all, then press <Ctrl+Q>, then release all... But normal behavior (in any Windows program) like pressing <Ctrl> then <J>, releasing J key, then press <Q>, all of that keeping <Ctrl> pressed, doesn't work and can't be detected.

I already report this to ServiceDesk (#826140), but without success, their reply was :

But I can't find a way to have it working well. So my opinion is that there is no reliable way to detect correctly combination of keys input. I would be happy if some can demonstrate that I am wrong.

Hi,

Noted on the SRC button.  The detection of <Ctrl+J> is quite reliable so far.  see the test program link .    The issue is the execution of code inside the <Ctrl+J> is not done properly.

Regards,

Toyogo

[Alain Verleyen]

toyogo00:

Hi,

Noted on the SRC button.  The detection of <Ctrl+J> is quite reliable so far.  see the test program link .    The issue is the execution of code inside the <Ctrl+J> is not done properly.

Regards,

Toyogo

Nope. I tried your code and it's working well. If use press <Ctrl+J> all 5 lines are displayed, if I press <Ctrl+Q> all 5 lines are removed.

The detection of <Ctrl+J> isn't always reliable. If I press <Ctrl> and keep it pressed, then I press <Q>, lines are removed, if I then press <J>, lines are not displayed. <Ctrl+J> is not detected. Anyway, it's probably not related to your issue, and I understand that it's sufficiently reliable for your need.