BCGControlBar Pro for MFC
virtual void CBCGPWinApp::OnBeforeChangeVisualTheme ( CBCGPAppOptions appOptions,
CWnd *  pMainWnd 

This method is called by the framework before changing the Visual Theme.

appOptionsThe reference to application options structure.
pMainWndThe pointer to application main window.

The default implementation does nothing. You can override this method to customize the application appearance before a visual theme changing.