BCGControlBar Pro for MFC
BOOL CBCGPTabWnd::SetTabStateAnimationImages ( UINT  uiAnimImagesResID,
int  cx = 16,
BOOL  bDPIAutoScale = TRUE,
COLORREF  clrTransp = RGB(255, 0, 255) 
)

Sets tab animation ("busy" indicator) images. The image list is loaded from the resources.

Parameters
uiAnimImagesResIDImage list resourc id.
cxWidth of each image, in pixels.
bDPIAutoScaleSpecifies whether the image list should be automatically scaled according to current DPI.
clrTranspThe image list transparent color. Not used if image list is 32 bpp.
Returns
TRUE if it succeeds, FALSE if it fails.