[DRAFT] Gesture navigation API + swipe implementation

[KovalevAndrey]

Description

Basic gesture API + Swipe implementation. Implemented as a Modifier which is applied to container composable.

If we agree on the API more gestures to come:

• draggable
• multi touching
• ..

Fixes #97

device-2022-08-25-120746.mp4

Check list

• I have updated CHANGELOG.md if required.
• I have updated documentation if required.

[LachlanMcKee]

Might be worth adding a video (when the PR is ready) to show how it works (with touches displayed)

[CherryPerry]

Are you sure that is what we need?

I imagined an implementation like in Telegram where a screen follows a finger. It would need to change Children/Child implementations to render not only top active item, but also top non-active.

[KovalevAndrey]

Are you sure that is what we need?

I imagined an implementation like in Telegram where a screen follows a finger. It would need to change Children/Child implementations to render not only top active item, but also top non-active.

We can discuss what we need but I can imaging it's a different API. The problem with this is that inChildren/Child you don't know in which states you children can be and this Telegram style navigation can be applied only for specific nav models like BackStack

[zsoltk]

@KovalevAndrey the gestures would be paired to a specific NavModel just like a TransitionHandler is, I don't see an issue with that (e.g. having horizontal swiping in Tiles wouldn't make too much sense). I'm also for the instant response to the gesture.

I think we could:

1. Use the swipeable api
2. Anchors would trigger NavModel operations
3. For an instant animation of a target we would need to apply the same Modifier as we do in the corresponding TransitionHandler.

Possibly we could make all TransitionHandlers expect to work with a Float-based transition spec (as in 0..1f progress), and expose the part which maps Float → Modifier. That way we could probably reuse it in the gesture handling.

[KovalevAndrey]

Closing for now as we're trying to implement a different approach for the way we handle transitions