Supercedes https://github.com/linebender/xilem/pull/411
This is designed with #417 in mind, to not lock-in to our event loop.
---------
Co-authored-by: Philipp Mildenberger <philipp@mildenberger.me>
Since we're suffering from the orphan rule with the new xilem_core
implementation, we cannot use `View` in downstream crates for external
types such as a `WidgetView` implementation for `&'static str` in Xilem.
This PR adds an `OrphanView` trait which the `Context` of the `View` has
to implement for the type which has an implementation in xilem_core for
this. The `View` impl for these types is basically a proxy for
`OrphanView` (which in turn has the same method signature as `View`), so
downstream crates can achieve the same as with the `View`.
---------
Co-authored-by: Daniel McNab <36049421+DJMcNab@users.noreply.github.com>
This:
1) Renames the current/old `xilem_core` to `xilem_web_core` and moves it
to the `xilem_web/xilem_web_core` folder
2) Creates a new `xilem_core`, which does not use (non-tuple) macros and
instead contains a `View` trait which is generic over the `Context` type
3) Ports `xilem` to this `xilem_core`, but with some functionality
missing (namely a few of the extra views; I expect these to
straightforward to port)
4) Ports the `mason` and `mason_android` examples to this new `xilem`,
with less functionality.
This continues ideas first explored in #235
The advantages of this new View trait are:
1) Improved support for ad-hoc views, such as views with additional
attributes.
This will be very useful for layout algorithms, and will also enable
native *good* multi-window (and potentially menus?)
2) A lack of macros, to better enable using go-to-definition and other
IDE features on the traits
Possible disadvantages:
1) There are a few more traits to enable the flexibility
2) It can be less clear what `Self::Element::Mut` is in the `rebuild`
function, because of how the resolution works
3) When implementing `View`, you need to specify the context (i.e.
`impl<State, Action> View<State, Action, [new] ViewCtx> for
Button<State, Action>`.
---------
Co-authored-by: Philipp Mildenberger <philipp@mildenberger.me>
Daniel McNab