New `frozen` option on route/screen layering

[Nonudian]

Problem to solve

Hello guys, I have an issue when I want a A screen to be the frozen background of a B screen. I initially created a new RouterComponent with those 2 screens (that are Components), and made the B screen transparent allowing me to see through, thus the A screen.

router = RouterComponent(
    routes: {
        'world': Route(WorldScreen.new), //A screen
        'collection': Route(CollectionScreen.new, transparent: true), //B screen
    },
    initialRoute: 'home',
),

But it doesn't work well. When I'm on the B screen, all events like tappables or draggables enabled on A screen are still triggered, as if the focus was on the 2 screens instead of the one we selected, thus the B screen.

We can also see that on the Flame router demo just below, when the Rate me button is still active and triggerable even if the dialog box is at foreground. That's a little bit problematic.

Proposal

An interesting thing could be a new option frozen on a Route, that precises that this route can't have its events triggered if a foreground route has the focus.

What do you think of it ?

[spydon]

Sounds like a good idea, I would name it something else though since frozen sounds like it would be frozen on the frame it was rendering when it was overlaid by another route. propagateEvents or something like that maybe.