The WM_WINDOWPOSCHANGED message is sent to a window whose size, position, or place in the Z order has changed as a result of a call to the SetWindowPos function or another window-management function.
A window receives this message through its WindowProc function.
Syntax
WM_WINDOWPOSCHANGED
WPARAM wParam
LPARAM lParam;
Parameters
- wParam
-
This parameter is not used.
- lParam
-
Pointer to a WINDOWPOS structure that contains information about the window's new size and position.
Return Value
If an application processes this message, it should return zero.
Remarks
By default, the DefWindowProc function sends the WM_SIZE and WM_MOVE messages to the window. The WM_SIZE and WM_MOVE messages are not sent if an application handles the WM_WINDOWPOSCHANGED message without calling DefWindowProc. It is more efficient to perform any move or size change processing during the WM_WINDOWPOSCHANGED message without calling DefWindowProc.
Notification Requirements
| Minimum DLL Version |
None |
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| Header | Declared in Winuser.h, include Windows.h |
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| Minimum operating systems |
Windows 95, Windows NT 3.1 |
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See Also
Windows Overview, DefWindowProc, EndDeferWindowPos, SetWindowPos, WINDOWPOS, WM_MOVE, WM_SIZE, WM_WINDOWPOSCHANGING