Called by the framework when a pane is about to float.
virtual BOOL OnBeforeFloat(
    CRect& rectFloat,
    AFX_DOCK_METHOD dockMethod
);
Parameters
- [in] rectFloat 
 Specifies the position and size of the pane when it is in a floating state.
- [in] dockMethod 
 Specifies the docking method of the pane.
Return Value
TRUE if the pane can be floated; otherwise, FALSE.
Remarks
This method is called by the framework when a pane is about to float. You can override this method in a derived class if you want to perform any processing before the pane finally floats.
Requirements
Header: afxPane.h