These define how the button responds to mouse clicks.
Standard push button behavior. The button hilites while the mouse is clicked
over it and unhilites when the mouse is moved outside of it or released.
If the mouse is released over the button, the xpMsg_PushButtonPressed message
Check box behavior. The button immediately toggles its value when the mouse is clicked and sends out a xpMsg_ButtonStateChanged message.
Radio button behavior. The button immediately sets its state to one
and sends out a xpMsg_ButtonStateChanged message if it was not already set
to one. You must turn off other radio buttons in a group in your code.