Current state of the display

[Natter]

Is it possible to know the current state of the display - enabled or disabled ?

FWH 17.04/xHarbour BCC7

[Antonio Linares]

https://stackoverflow.com/questions/203355/is-there-any-way-to-detect-the-monitor-state-in-windows-on-or-off

[Natter]

Antonio, thanks for your help !

The GetDevicePowerState function takes two parameters. The first parameter is a handle monitor. And how to find it ?

[Antonio Linares]

Based on this example:

https://stackoverflow.com/questions/31579658/how-do-i-get-the-status-of-a-display

You could do:

#define MONITOR_DEFAULTTOPRIMARY 1

BOOL bResult;

GetDevicePowerState( MonitorFromWindow( FindWindow( 0, 0 ), MONITOR_DEFAULTTOPRIMARY ), &bResult )

https://msdn.microsoft.com/en-us/library/windows/desktop/dd145064(v=vs.85).aspx

[Natter]

I have written so:

Code: Select all  Expand view

#include "FiveWin.ch"

#define MONITOR_DEFAULTTOPRIMARY  1

function Main()
local bResult

  GetDevicePowerState( MonitorFromWindow( FindWindow( 0, 0 ),                     MONITOR_DEFAULTTOPRIMARY ), @bResult )
return nil

DLL32 Function GetDevicePowerState(hDevice AS DWORD, @bResult AS BOOL)   AS BOOL PASCAL  FROM "GetDevicePowerState" LIB "kernel32.dll"
DLL32 Function MonitorFromWindow(hDevice AS LONG, pr AS DWORD)   AS BOOL PASCAL  FROM "GetDevicePowerState" LIB "user32.dll"

The function MonitorFromWindow() returns empty. What is my mistake ?

[Antonio Linares]

DLL32 Function MonitorFromWindow(hDevice AS LONG, pr AS DWORD) AS BOOL PASCAL FROM "MonitorFromWindow" LIB "user32.dll"

[Antonio Linares]

DLL32 Function MonitorFromWindow( hDevice AS LONG, pr AS LONG ) AS LONG PASCAL FROM "MonitorFromWindow" LIB "user32.dll"

[Natter]

Еhank you, corrected. Now the function GetDevicePowerState returns .F. in any case. And when the display is on and when I turn it off by
SendMessage(HWND_BROADCAST, WM_SYSCOMMAND, SC_MONITORPOWER, 2)