HOWTO: Use GetForegroundWindow() When Desktop Is Not Active

• Microsoft Win32 Software Development Kit (SDK), used with:
  • Microsoft Windows NT versions 3.1, 3.5, 4.0
  • Microsoft Windows 2000

SUMMARY

GetForegroundWindow() is documented to return the handle of the foreground window, that is, the window that the user is currently working with. The proper handle is returned when the desktop that the application is running on is active; however, when another desktop is active, GetForegroundWindow() returns NULL.

This is expected behavior. There is no way to get the active window in your own desktop while another desktop is active.

The application desktop is one desktop. Other desktops include the logon and screen saver desktops. If GetForegroundWindow() returned a handle to the logon dialog box, it would be possible to create an application that could get user passwords. This would violate Windows NT security.

For this reason, it is not possible to create screen savers that melt or drop out.

Additional query words:

Keywords : kbNTOS310 kbNTOS350 kbNTOS400 kbWinOS2000 kbSDKWin32 kbGrpUser kbWndw
Version : WINDOWS:
Platform : WINDOWS
Issue type : kbhowto