BCGControlBar Pro for MFC
virtual BOOL CBCGPToolbarButton::OnBeforeDrop ( CBCGPToolBar pTarget)

Called by the framework before button is dropped on target.

This function is called by the framework just before the button is dropped on target. Override this function in a derived class to enable/disable drop on custom targets.

The default implementation returns TRUE.

pTargetThe target toolbar
Should return TRUE if a button can be dropped on target; otherwise FALSE.