improv: operation and select for directional navigation

core/src/widget/operation.rs

@@ -9,7 +9,7 @@ pub use scrollable::Scrollable;
 pub use text_input::TextInput;
 
 use crate::widget::Id;
-use crate::{Rectangle, Vector};
+use crate::{Rectangle, Vector, window};
 
 use std::any::Any;
 use std::fmt;
@@ -75,6 +75,9 @@ pub trait Operation<T = ()>: Send {
     fn finish(&self) -> Outcome<T> {
         Outcome::None
     }
+
+    /// Track the active window id being processed if relevant to the operation
+    fn set_window_id(&mut self, _id: window::Id) {}
 }
 
 impl<T, O> Operation<O> for Box<T>
@@ -140,6 +143,10 @@ where
     fn finish(&self) -> Outcome<O> {
         self.as_ref().finish()
     }
+
+    fn set_window_id(&mut self, id: window::Id) {
+        self.as_mut().set_window_id(id);
+    }
 }
 
 /// The result of an [`Operation`].
@@ -243,6 +250,10 @@ where
         fn finish(&self) -> Outcome<O> {
             Outcome::None
         }
+
+        fn set_window_id(&mut self, id: window::Id) {
+            self.operation.set_window_id(id);
+        }
     }
 
     BlackBox { operation }
@@ -410,6 +421,10 @@ where
                 })),
             }
         }
+
+        fn set_window_id(&mut self, id: window::Id) {
+            self.operation.set_window_id(id);
+        }
     }
 
     Map {
@@ -515,6 +530,10 @@ where
                 }
             }
         }
+
+        fn set_window_id(&mut self, id: window::Id) {
+            self.operation.set_window_id(id);
+        }
     }
 
     Chain {
@@ -566,6 +585,10 @@ pub fn scoped<T: 'static>(
                 outcome => outcome,
             }
         }
+
+        fn set_window_id(&mut self, id: window::Id) {
+            self.operation.set_window_id(id);
+        }
     }
 
     ScopedOperation {

runtime/src/widget/selector.rs

@@ -1,6 +1,6 @@
 //! Find and query widgets in your applications.
 pub use iced_selector::{
-    Bounded, Candidate, Selector, Target, Text, id, is_focused,
+    Bounded, Candidate, Selector, Target, Text, focus, id, is_focused,
 };
 
 use crate::Task;

selector/src/find.rs

@@ -1,3 +1,5 @@
+use iced_core::window;
+
 use crate::Selector;
 use crate::core::widget::operation::{
     Focusable, Outcome, Scrollable, TextInput,
@@ -100,6 +102,10 @@ where
     fn finish(&self) -> Self::Output {
         self.outputs.clone()
     }
+
+    fn set_window_id(&mut self, id: window::Id) {
+        self.selector.set_window_id(id);
+    }
 }
 
 pub trait Strategy {
@@ -110,6 +116,8 @@ pub trait Strategy {
     fn is_done(&self) -> bool;
 
     fn finish(&self) -> Self::Output;
+
+    fn set_window_id(&mut self, _id: window::Id) {}
 }
 
 #[derive(Debug)]
@@ -273,4 +281,8 @@ where
     fn finish(&self) -> Outcome<S::Output> {
         Outcome::Some(self.strategy.finish())
     }
+
+    fn set_window_id(&mut self, id: window::Id) {
+        self.strategy.set_window_id(id);
+    }
 }

selector/src/lib.rs

@@ -1,5 +1,6 @@
 //! Select data from the widget tree.
 use iced_core as core;
+use iced_core::window;
 
 mod find;
 mod target;
@@ -48,6 +49,8 @@ pub trait Selector {
     {
         FindAll::new(find::All::new(self))
     }
+
+    fn set_window_id(&mut self, _id: window::Id) {}
 }
 
 impl Selector for &str {
@@ -171,3 +174,40 @@ pub fn is_focused() -> impl Selector<Output = Target> {
 
     IsFocused
 }
+
+/// Returns a [`Selector`] that matches widgets that are focusable.
+pub fn focus() -> impl Selector<Output = (bool, Target, window::Id)> {
+    struct Focus {
+        cur_window_id: window::Id,
+    }
+
+    impl Selector for Focus {
+        type Output = (bool, Target, window::Id);
+
+        fn select(&mut self, candidate: Candidate<'_>) -> Option<Self::Output> {
+            if let Candidate::Focusable { state, .. } = candidate {
+                Some((
+                    state.is_focused(),
+                    Target::from(candidate),
+                    self.cur_window_id,
+                ))
+            } else if matches!(candidate, Candidate::Scrollable { .. }) {
+                Some((false, Target::from(candidate), self.cur_window_id))
+            } else {
+                None
+            }
+        }
+
+        fn description(&self) -> String {
+            "is focusable and focused".to_owned()
+        }
+
+        fn set_window_id(&mut self, id: iced_core::window::Id) {
+            self.cur_window_id = id;
+        }
+    }
+
+    Focus {
+        cur_window_id: window::Id::NONE,
+    }
+}

widget/src/button.rs

@@ -267,6 +267,7 @@ struct State {
     is_hovered: bool,
     is_pressed: bool,
     is_focused: bool,
+    needs_redraw: bool,
 }
 
 impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
@@ -368,6 +369,12 @@ where
             viewport,
         );
 
+        let state = tree.state.downcast_mut::<State>();
+        if state.needs_redraw {
+            state.needs_redraw = false;
+            shell.request_redraw();
+        }
+
         if shell.is_event_captured() {
             return;
         }
@@ -777,11 +784,11 @@ impl Default for Style {
 ///
 /// impl Catalog for MyTheme {
 ///     type Class<'a> = ButtonClass;
-///     
+///
 ///     fn default<'a>() -> Self::Class<'a> {
 ///         ButtonClass::default()
 ///     }
-///     
+///
 ///
 ///     fn style(&self, class: &Self::Class<'_>, status: Status) -> Style {
 ///         let mut style = Style::default();
@@ -1000,10 +1007,12 @@ impl operation::Focusable for State {
     }
 
     fn focus(&mut self) {
+        self.needs_redraw |= !self.is_focused;
         self.is_focused = true;
     }
 
     fn unfocus(&mut self) {
+        self.needs_redraw |= self.is_focused;
         self.is_focused = false;
     }
 }

widget/src/scrollable.rs

@@ -676,14 +676,6 @@ where
         let translation =
             state.translation(self.direction, bounds, content_bounds);
 
-        operation.scrollable(
-            Some(&self.id),
-            bounds,
-            content_bounds,
-            translation,
-            state,
-        );
-
         operation.traverse(&mut |operation| {
             self.content.as_widget_mut().operate(
                 &mut tree.children[0],
@@ -696,6 +688,14 @@ where
                 operation,
             );
         });
+        // XXX must be done after traversing to perform DFS
+        operation.scrollable(
+            Some(&self.id),
+            bounds,
+            content_bounds,
+            translation,
+            state,
+        );
     }
 
     fn update(

winit/src/lib.rs

@@ -2519,6 +2519,8 @@ where
             while let Some(mut operation) = current_operation.take() {
                 for (id, ui) in interfaces.iter_mut() {
                     if let Some(window) = window_manager.get_mut(*id) {
+                        operation.as_mut().set_window_id(*id);
+
                         ui.operate(&window.renderer, operation.as_mut());
                     }
                 }