NotifyControls sends a message with the message ID passed in the Msg parameter to all the controls in the windowed control's Controls array property. NotifyControls is used to update all the controls in a form of such occurrences as changes in the parent color or font.  

NotifyControls constructs a generic message record, filling its message ID field with the value of Msg and setting its parameter and result fields to zeros, then calls the Broadcast method to send the message to all the child controls. 

Broadcast 

Controls