Microsoft KB Archive/62068

{|
 * width="100%"|

HOWTO: Ignore WM_MOUSEACTIVATE Message for an MDI Window

 * }

Q62068

-

The information in this article applies to:


 * Microsoft Windows Software Development Kit (SDK)
 * Microsoft Win32 Software Development Kit (SDK)

-

SUMMARY
To make an MDI window to become active and have the caret be in the same position as when the window was last active you need to process the WM_MOUSEACTIVATE message and return MA_ACTIVATEANDEAT for the first time. Therefore, you need to set a Boolean flag in the WM_MDIACTIVATE message so that the return is set only once. The sample code below can be used to modify the MULTIPAD sample application. Also, the following is documentation on MA_ACTIVATE* messages, taken from the Windows 3.0 final SDK README.WRI file:

  WM_MOUSEACTIVATE

Return Value   The return value specifies whether the window should be activated and whether the mouse event should be discarded. It must be one of the following values:

Value                  Meaning -                  ---                   MA_ACTIVATE             Activate the window. MA_NOACTIVATE          Do not activate the window. MA_ACTIVATEANDEAT      Activate the window and discard the mouse event.

Sample Code
  /* --- multipad.c  MPMDIWndProc section --- */

case WM_MOUSEACTIVATE:  // Added. if (bEatMessage) { bEatMessage = FALSE; return (LONG)MA_ACTIVATEANDEAT ; }       /* Else, break. */        break;

case WM_MDIACTIVATE: /* If you are activating this child, remember it. */        if (wParam){ hwndActive    = hwnd; hwndActiveEdit = (HWND)GetWindowWord (hwnd, GWW_HWNDEDIT); bEatMessage = TRUE;     // added }       else{ hwndActive    = NULL; hwndActiveEdit = NULL; }       break; Additional query words:

Keywords : kbMDI kbOSWinNT kbOSWin2000 kbSDKWin32 kbGrpDSUser kbOSWin kbWndw kbWndwMsg

Issue type : kbhowto

Technology : kbWin32SDKSearch kbAudDeveloper kbSDKSearch kbWin32sSearch kbWinSDKSearch