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 WM_CTLCOLORSCROLLBAR

The WM_CTLCOLORSCROLLBAR message is sent to the parent window of a scroll bar control when the control is about to be drawn. By responding to this message, the parent window can use the display context handle to set the background color of the scroll bar control.

A window receives this message through its WindowProc function.

Parameters

• wParam
  Handle to the device context for the scroll bar control.
• lParam
  Handle to the scroll bar.

Return Value

If an application processes this message, it must return the handle to a brush. The system uses the brush to paint the background of the scroll bar control.

Remarks

By default, the DefWindowProc function selects the default system colors for the scroll bar control.

The WM_CTLCOLORSCROLLBAR message is never sent between threads; it is only sent within the same thread.

If a dialog box procedure handles this message, it should cast the desired return value to a BOOL and return the value directly. If the dialog box procedure returns FALSE, then default message handling is performed. The DWL_MSGRESULT value set by the SetWindowLong function is ignored.

The WM_CTLCOLORSCROLLBAR message is used only by child scrollbar controls. Scrollbars attached to a window (WS_SCROLL and WS_VSCROLL) do not generate this message. To customize the appearance of scrollbars attached to a window, use the flat scroll bar functions.

Notification Requirements

• Minimum DLL Version None
• Header Declared in Winuser.h, include Windows.h
• Minimum operating systems Windows 95, Windows NT 3.1

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Notebook exported on Monday, 7 July 2008, 18:56:50 PM Eastern Daylight Time