Add support for `impl View for Arc/Rc<impl View>`

[Philipp-M]

[jaredoconnell]

Now, or later when the examples are improved, this would definitely benefit from a brief example.

[Philipp-M]

Now, or later when the examples are improved, this would definitely benefit from a brief example.

You're right, I could add one here, that shows a use-case for this (it's an alternative to Memoize)

[Philipp-M]

Good idea to mention the example, I've implemented it via an example for memoization and quite a few views were not yet exported... It also revealed a bomb:

View needs to be Sync to support Arc<impl View>.

I think if we want to store shared views in general in the app state this requirement will come sooner or later (e.g. by supporting a rope of views as a ViewSequence).

[Philipp-M]

Ok, at least for View::State, Sync bounds are not necessary. I've relaxed this via adjustments in the macros.

[Philipp-M]

I have added impl View for Arc<dyn AnyView> as well (resolves the TODO in the example and makes everything a little bit cleaner).

[Philipp-M]

I've added the super bounds of View to AnyView as well, to avoid Box<dyn AnyView + Send + Sync>

[Philipp-M]

Whoops, I was a little bit too eager with deleting old branches...

[DJMcNab]

I think this can be closed - this is included in #310

[Philipp-M]

Yes it can be closed