We can override the constructor as normal, but be careful not to mess around with the window here! The window does not belong to this state object yet: another state object is using it.

This method is called right after our state object looses ownership of the window. The window is automatically reset, but if you modified anything other than the window, this is where you should clean it up.

This method is called right after our state object gains ownership over the window. Now we can perform operations that modify the window.