BCGControlBar Pro for MFC
virtual BOOL CBCGPColorBar::OpenColorDialog ( const COLORREF  colorDefault,
COLORREF &  colorRes 

Called by the framework when user is about to open a color dialog

Nonzero if the user has selected a color; 0 if the user canceled a selection.

Override this member function if you need to take special actions when the color dialog is being opened.

colorDefaultSpecifies a default color to be selected when the color dialog has opened
colorResOut value, specifies a color that has been selected by user