BCGControlBar Pro for MFC
BOOL CBCGPFrameWnd::SetDockingBarsIconList ( UINT  nResID,
const CSize &  sizeIcon = CSize(16, 16),
COLORREF  clrTransparent = RGB(255, 0, 255),
BOOL  bAutoScale = TRUE 

Specify a docking bars (panes) icon list.

nResIDIconst list resource ID (BMP, PNG or SVG).
sizeIconIcon size.
clrTransparentTransparent color.
bAutoScaleSpecifies whether the icon list is automatically scaled according to current DPI.
Returns True if image list is successfully loaded; FALSE - otherwise.