BCGControlBar Pro for MFC
UINT BCGM_GETDOCUMENTCOLORS

The message is sent to the main frame window.

Parameters
wParamThis parameter is not used.
lParam[out]Pointer to a CList<COLORREF, COLORREF> object.
Returns
Should be 0.

This message is sent to the main frame window from CBCGPColorMenuButton to retrieve the document colors.