Platform SDK: Interprocess Communications

WM_CHANGECBCHAIN

The WM_CHANGECBCHAIN message is sent to the first window in the clipboard viewer chain when a window is being removed from the chain.

A window receives this message through its WindowProc function.

LRESULT CALLBACK WindowProc(
  HWND hwnd,       // handle to window
  UINT uMsg,       // WM_CHANGECBCHAIN
  WPARAM wParam,   // handle to window to be removed (HWND)
  LPARAM lParam    // handle to next window in chain (HWND)
);

Parameters

wParam
Handle to the window being removed from the clipboard viewer chain.
lParam
Handle to the next window in the chain following the window being removed. This parameter is NULL if the window being removed is the last window in the chain.

Return Values

If an application processes this message, it should return zero.

Remarks

Each clipboard viewer window saves the handle to the next window in the clipboard viewer chain. Initially, this handle is the return value of the SetClipboardViewer function.

When a clipboard viewer window receives the WM_CHANGECBCHAIN message, it should call the SendMessage function to pass the message to the next window in the chain, unless the next window is the window being removed. In this case, the clipboard viewer should save the handle specified by the lParam parameter as the next window in the chain.

Requirements

  Windows NT/2000: Requires Windows NT 3.1 or later.
  Windows 95/98: Requires Windows 95 or later.
  Header: Declared in Winuser.h; include Windows.h.

See Also

Clipboard Overview, Clipboard Messages, SendMessage, SetClipboardViewer