Windows 7 Display on/off event issue?

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rajan_m
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Windows 7 Display on/off event issue?

Post by rajan_m » Fri Jul 31, 2015 2:13 pm

Hi,

I'm trying to capture display on/off event using following code, able to capture off event but not on.

Code: Select all

WXLRESULT MyFrame::MSWWindowProc(WXUINT nMsg, WXWPARAM wParam, WXLPARAM lParam)
{
	wxTextCtrl* textctrl = (wxTextCtrl*)FindWindowById(MOUSE_TEXT,this);
 
	if(nMsg == WM_SYSCOMMAND )
	{
		if(wParam == SC_MONITORPOWER)
		{
			if(lParam == -1)
				textctrl->AppendText("monitor on\n");	//not working

			if(lParam == 2)
				textctrl->AppendText("monitor off"));	//working
		}
	}
}
I'm not understanding where its going wrong. Help me to solve this issue.

Regards,
Rajan.M
Every exit is an entry somewhere else!

DenDev
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Re: Windows 7 Display on/off event issue?

Post by DenDev » Fri Jul 31, 2015 2:34 pm

It might be caused by a signing issue, have you tried casting -1 to WXLPARAM?

Code: Select all

...
if(lParam == (WXLPARAM)-1) textctrl->AppendText("monitor on\n");
...
If this does not help you can try to log the value of lParam on order to see what the value is when the monitor is turned on.
I have a bad habbit of not testing the code I post :D

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doublemax
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Re: Windows 7 Display on/off event issue?

Post by doublemax » Fri Jul 31, 2015 2:45 pm

If i understand the MSDN documentation correctly, these commands can be used to actively change the monitor power status, not to get notified when it changes.
Use the source, Luke!

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