Platform SDK: Interprocess Communications

WM_VSCROLLCLIPBOARD

The WM_VSCROLLCLIPBOARD message is sent to the clipboard owner by a clipboard viewer window when the clipboard contains data in the CF_OWNERDISPLAY format and an event occurs in the clipboard viewer's vertical scroll bar. The owner should scroll the clipboard image and update the scroll bar values.

A window receives this message through its WindowProc function.

LRESULT CALLBACK WindowProc(
  HWND hwnd,      // handle to window
  UINT uMsg,      // WM_VSCROLLCLIPBOARD
  WPARAM wParam,  // handle to window (HWND)
  LPARAM lParam   // scroll bar code and scroll box position
);

Parameters

wParam
Handle to the clipboard viewer window.
lParam
The low-order word of lParam specifies a scroll bar event. This parameter can be one of the following values.
Value Meaning
SB_BOTTOM Scroll to lower right.
SB_ENDSCROLL End scroll.
SB_LINEDOWN Scroll one line down.
SB_LINEUP Scroll one line up.
SB_PAGEDOWN Scroll one page down.
SB_PAGEUP Scroll one page up.
SB_THUMBPOSITION Scroll to absolute position. The current position is specified by the high-order word.
SB_TOP Scroll to upper left.

The high-order word of lParam specifies the current position of the scroll box if the low-order word of lParam is SB_THUMBPOSITION; otherwise, the high-order word of lParam is not used.

Return Values

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

Remarks

The clipboard owner can use the ScrollWindow function to scroll the image in the clipboard viewer window and invalidate the appropriate region.

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, HIWORD, LOWORD, ScrollWindow