Function on_state_changed 

pub fn on_state_changed(
    child: impl IntoUiNode,
    handler: Handler<WindowChangedArgs>,
) -> UiNode

P On window state changed.

This event notifies every time the window state changes.

Note that you can also track the window state by setting state to a read-write variable.

This property is the same as on_pre_window_state_changed.