WM_SIZECLIPBOARD

2.x

WM_SIZECLIPBOARD
hwndViewer = (HWND) wParam;      /* handle of clipboard viewer */
hglb = (HGLOBAL) LOWORD(lParam); /* handle of global object    */

The WM_SIZECLIPBOARD message is sent by the clipboard viewer to the clipboard owner when the clipboard contains data with the CF_OWNERDISPLAY attribute and the size of the client area of the clipboard-viewer window has changed.

Parameters

hwndViewer

Value of wParam. Identifies the clipboard-application window.

hglb

Value of the low-order word of lParam. Identifies a global memory object that contains a RECT data structure. The structure specifies the area that the clipboard owner should paint. The RECT structure has the following form:

typedef struct tagRECT {    /* rc */
   int left;
   int top;
   int right;
   int bottom;
} RECT;

Return Value

An application should return zero if it processes this message.

Comments

A WM_SIZECLIPBOARD message is sent with a null rectangle (0,0,0,0) as the new size when the clipboard application is about to be destroyed or minimized. This permits the clipboard owner to free its display resources.

An application must use the GlobalLock function to lock the memory that contains the RECT data structure. The application should unlock that memory by using the GlobalUnlock function before it yields or returns control.