Block input

[Tim-Revision]

While implementing this package in our app to improve the esthetics of our side menu we noticed that the inputs are still able to be processed by the main page when the side menu is open. I've tried to circumvent this issue by wrapping the scaffold in an ignore pointer but there is no way to let our ignore pointer know that the close button has been pressed. Thus I propose this change which would allow the input to the main page to be blocked if preferred. This would not be a breaking change but simply add an extra option to the Side Menu.