Implement Operation::finish for action::widget::Map

native/src/widget/action.rs

@@ -3,6 +3,8 @@ use crate::widget::Id;
 
 use iced_futures::MaybeSend;
 
+use std::rc::Rc;
+
 /// An operation to be performed on the widget tree.
 #[allow(missing_debug_implementations)]
 pub struct Action<T>(Box<dyn Operation<T>>);
@@ -24,7 +26,7 @@ impl<T> Action<T> {
     {
         Action(Box::new(Map {
             operation: self.0,
-            f: Box::new(f),
+            f: Rc::new(f),
         }))
     }
 
@@ -37,7 +39,7 @@ impl<T> Action<T> {
 #[allow(missing_debug_implementations)]
 struct Map<A, B> {
     operation: Box<dyn Operation<A>>,
-    f: Box<dyn Fn(A) -> B>,
+    f: Rc<dyn Fn(A) -> B>,
 }
 
 impl<A, B> Operation<B> for Map<A, B>
@@ -50,38 +52,44 @@ where
         id: Option<&Id>,
         operate_on_children: &mut dyn FnMut(&mut dyn Operation<B>),
     ) {
-        struct MapRef<'a, A, B> {
+        struct MapRef<'a, A> {
             operation: &'a mut dyn Operation<A>,
-            f: &'a dyn Fn(A) -> B,
         }
 
-        impl<'a, A, B> Operation<B> for MapRef<'a, A, B> {
+        impl<'a, A, B> Operation<B> for MapRef<'a, A> {
             fn container(
                 &mut self,
                 id: Option<&Id>,
                 operate_on_children: &mut dyn FnMut(&mut dyn Operation<B>),
             ) {
-                let Self { operation, f } = self;
+                let Self { operation, .. } = self;
 
                 operation.container(id, &mut |operation| {
-                    operate_on_children(&mut MapRef { operation, f });
+                    operate_on_children(&mut MapRef { operation });
                 });
             }
 
-            fn scrollable(&mut self, state: &mut dyn Scrollable, id: Option<&Id>) {
+            fn scrollable(
+                &mut self,
+                state: &mut dyn Scrollable,
+                id: Option<&Id>,
+            ) {
                 self.operation.scrollable(state, id);
             }
 
-            fn focusable(&mut self, state: &mut dyn Focusable, id: Option<&Id>) {
+            fn focusable(
+                &mut self,
+                state: &mut dyn Focusable,
+                id: Option<&Id>,
+            ) {
                 self.operation.focusable(state, id);
             }
         }
 
-        let Self { operation, f } = self;
+        let Self { operation, .. } = self;
 
         MapRef {
             operation: operation.as_mut(),
-            f,
         }
         .container(id, operate_on_children);
     }
@@ -109,4 +117,19 @@ where
     ) {
         self.operation.text_input(state, id);
     }
+
+    fn finish(&self) -> operation::Outcome<B> {
+        match self.operation.finish() {
+            operation::Outcome::None => operation::Outcome::None,
+            operation::Outcome::Some(output) => {
+                operation::Outcome::Some((self.f)(output))
+            }
+            operation::Outcome::Chain(next) => {
+                operation::Outcome::Chain(Box::new(Map {
+                    operation: next,
+                    f: self.f.clone(),
+                }))
+            }
+        }
+    }
 }