These messages are sent by the button to itself and then up the widget chain when the button is clicked. (You may intercept them by providing a widget handler for the button itself or by providing a handler in a parent widget.)
This message is sent when the user completes a click and release in a button with
push button behavior. Parameter
one of the message is the widget ID of the button. This message is dispatched up the
This message is sent when a button is clicked that has radio button or check box behavior
and its value changes. (Note that if the value changes by setting a property you do not receive
this message!) Parameter one is the widget ID of the button, parameter 2 is the new state value,
either zero or one. This message is dispatched up the widget hierarchy.