Add AdaptState view

Co-authored-by: Philipp Mildenberger <philipp@mildenberger.me>

crates/xilem_core/src/view/adapt.rs

@@ -160,3 +160,75 @@ macro_rules! generate_adapt_view {
  }
  };
 }
+
+#[macro_export]
+macro_rules! generate_adapt_state_view {
+ ($viewtrait:ident, $cx:ty, $changeflags:ty) => {
+ /// A view that wraps a child view and modifies the state that callbacks have access to.
+ pub struct AdaptState<
+ ParentT,
+ ChildT,
+ V,
+ F: Fn(&mut ParentT) -> &mut ChildT = fn(&mut ParentT) -> &mut ChildT,
+ > {
+ f: F,
+ child: V,
+ phantom: std::marker::PhantomData<fn() -> (ParentT, ChildT)>,
+ }
+
+ impl<ParentT, ChildT, V, F: Fn(&mut ParentT) -> &mut ChildT + Send>
+ AdaptState<ParentT, ChildT, V, F>
+ {
+ pub fn new(f: F, child: V) -> Self {
+ Self {
+ f,
+ child,
+ phantom: Default::default(),
+ }
+ }
+ }
+
+ impl<
+ ParentT,
+ ChildT,
+ A,
+ V: $viewtrait<ChildT, A>,
+ F: Fn(&mut ParentT) -> &mut ChildT + Send,
+ > $viewtrait<ParentT, A> for AdaptState<ParentT, ChildT, V, F>
+ {
+ type State = V::State;
+ type Element = V::Element;
+
+ fn build(&self, cx: &mut $cx) -> ($crate::Id, Self::State, Self::Element) {
+ self.child.build(cx)
+ }
+
+ fn rebuild(
+ &self,
+ cx: &mut $cx,
+ prev: &Self,
+ id: &mut $crate::Id,
+ state: &mut Self::State,
+ element: &mut Self::Element,
+ ) -> $changeflags {
+ self.child.rebuild(cx, &prev.child, id, state, element)
+ }
+
+ fn message(
+ &self,
+ id_path: &[$crate::Id],
+ state: &mut Self::State,
+ message: Box<dyn std::any::Any>,
+ app_state: &mut ParentT,
+ ) -> $crate::MessageResult<A> {
+ self.child
+ .message(id_path, state, message, (self.f)(app_state))
+ }
+ }
+
+ impl<ParentT, ChildT, V, F: Fn(&mut ParentT) -> &mut ChildT> ViewMarker
+ for AdaptState<ParentT, ChildT, V, F>
+ {
+ }
+ };
+}

crates/xilem_html/src/lib.rs

@@ -27,7 +27,9 @@ pub use element::{element, Element, ElementState};
 #[cfg(feature = "typed")]
 pub use event::events;
 pub use event::{on_event, Action, Event, OnEvent, OnEventState, OptionalAction};
-pub use view::{Adapt, AdaptThunk, AnyView, Either, Pod, View, ViewMarker, ViewSequence};
+pub use view::{
+ Adapt, AdaptState, AdaptThunk, AnyView, Either, Pod, View, ViewMarker, ViewSequence,
+};
 #[cfg(feature = "typed")]
 pub use view_ext::ViewExt;
 

crates/xilem_html/src/view.rs

@@ -102,6 +102,7 @@ xilem_core::generate_viewsequence_trait! {ViewSequence, View, ViewMarker, DomNod
 xilem_core::generate_anyview_trait! {AnyView, View, ViewMarker, Cx, ChangeFlags, AnyNode, BoxedView;}
 xilem_core::generate_memoize_view! {Memoize, MemoizeState, View, ViewMarker, Cx, ChangeFlags, s, memoize}
 xilem_core::generate_adapt_view! {View, Cx, ChangeFlags}
+xilem_core::generate_adapt_state_view! {View, Cx, ChangeFlags}
 
 /// This view container can switch between two views.
 ///

src/view/mod.rs

@@ -28,4 +28,4 @@ pub use xilem_core::{Id, IdPath, VecSplice};
 pub use button::button;
 pub use linear_layout::{h_stack, v_stack, LinearLayout};
 pub use list::{list, List};
-pub use view::{Adapt, Cx, Memoize, View, ViewMarker, ViewSequence};
+pub use view::{Adapt, AdaptState, Cx, Memoize, View, ViewMarker, ViewSequence};

src/view/view.rs

@@ -28,6 +28,7 @@ xilem_core::generate_viewsequence_trait! {ViewSequence, View, ViewMarker, Widget
 xilem_core::generate_anyview_trait! {AnyView, View, ViewMarker, Cx, ChangeFlags, AnyWidget, BoxedView; + Send}
 xilem_core::generate_memoize_view! {Memoize, MemoizeState, View, ViewMarker, Cx, ChangeFlags, s, memoize}
 xilem_core::generate_adapt_view! {View, Cx, ChangeFlags}
+xilem_core::generate_adapt_state_view! {View, Cx, ChangeFlags}
 
 #[derive(Clone)]
 pub struct Cx {