WM_HSCROLLCLIPBOARD

The WM_HSCROLLCLIPBOARD message is sent to the clipboard owner by a clipboard viewer window. This occurs when the clipboard contains data in the CF_OWNERDISPLAY format and an event occurs in the clipboard viewer's horizontal 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_HSCROLLCLIPBOARD
  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_ENDSCROLL	End scroll.
SB_LEFT	Scroll to upper left.
SB_RIGHT	Scroll to lower right.
SB_LINELEFT	Scrolls left by one unit.
SB_LINERIGHT	Scrolls right by one unit.
SB_PAGELEFT	Scrolls left by the width of the window.
SB_PAGERIGHT	Scrolls right by the width of the window.
SB_THUMBPOSITION	Scroll to absolute position. The current position is specified by the high-order word.

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 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