How are the states of RadButton changing

Hi team,

When I try to customize the styles and templates of RadButton, I am blocked by the states transition of RadButton. There are focused and unfocused states, also there are normal, pressed and mouse over states. The normal, pressed and mouse over states are straightforward to comprehesive. However, i don't quite understand how the focused and unfocused states work when a user click the button.

 Thanks,

Jingfei