Is there Windows system event on active window changed?
Solution 1:
Yes, you can use SetWinEventHook function.
hEvent = SetWinEventHook(EVENT_SYSTEM_FOREGROUND ,
EVENT_SYSTEM_FOREGROUND , NULL,
WinEventProcCallback, 0, 0,
WINEVENT_OUTOFCONTEXT | WINEVENT_SKIPOWNPROCESS);
.......
VOID CALLBACK WinEventProcCallback ( HWINEVENTHOOK hWinEventHook, DWORD dwEvent, HWND hwnd, LONG idObject, LONG idChild, DWORD dwEventThread, DWORD dwmsEventTime)
{
/* your code here */
}
Solution 2:
There's the WM_ACTIVATE message, which is sent to the activated and deactivated windows.