feat: 'Toggler' animation

Cargo.toml

@@ -67,6 +67,8 @@ auto-detect-theme = ["iced_core/auto-detect-theme"]
 strict-assertions = ["iced_renderer/strict-assertions"]
 # Redraws on every runtime event, and not only when a widget requests it
 unconditional-rendering = ["iced_winit/unconditional-rendering"]
+# Enables widget animations
+animations = ["iced_widget/animations"]
 
 [dependencies]
 iced_core.workspace = true

core/src/animation.rs

@@ -101,6 +101,17 @@ where
         self.raw.transition(new_state, Instant::now());
     }
 
+    /// Instantaneously transitions the [`Animation`] from its current state to the given new state.
+    pub fn force(mut self, new_state: T) -> Self {
+        self.force_mut(new_state);
+        self
+    }
+
+    /// Instantaneously transitions the [`Animation`] from its current state to the given new state, by reference.
+    pub fn force_mut(&mut self, new_state: T) {
+        self.raw.transition_instantaneous(new_state, Instant::now());
+    }
+
     /// Returns true if the [`Animation`] is currently in progress.
     ///
     /// An [`Animation`] is in progress when it is transitioning to a different state.

core/src/theme/palette.rs

@@ -623,15 +623,17 @@ fn lighten(color: Color, amount: f32) -> Color {
     from_hsl(hsl)
 }
 
-fn deviate(color: Color, amount: f32) -> Color {
+/// Lighten dark colors and darken light ones by the specefied amount.
+pub fn deviate(color: Color, amount: f32) -> Color {
     if is_dark(color) {
         lighten(color, amount)
     } else {
         darken(color, amount)
     }
 }
 
-fn mix(a: Color, b: Color, factor: f32) -> Color {
+/// Mix with another color with the given ratio (from 0 to 1)
+pub fn mix(a: Color, b: Color, factor: f32) -> Color {
     let a_lin = Rgb::from(a).into_linear();
     let b_lin = Rgb::from(b).into_linear();
 

examples/animations/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "animations"
+version = "0.1.0"
+authors = ["LazyTanuki"]
+edition = "2021"
+publish = false
+
+[dependencies]
+iced.workspace = true
+iced.features = ["animations"]

examples/animations/README.md

@@ -0,0 +1,12 @@
+# Animations
+
+An application to showcase Iced widgets that have default animations.
+
+The __[`main`]__ file contains all the code of the example.
+
+You can run it with `cargo run`:
+```
+cargo run --package animations
+```
+
+[`main`]: src/main.rs

examples/animations/src/main.rs

@@ -0,0 +1,49 @@
+use iced::{
+    widget::{column, Toggler},
+    Element, Task, Theme,
+};
+
+pub fn main() -> iced::Result {
+    iced::application("Animated widgets", Animations::update, Animations::view)
+        .theme(Animations::theme)
+        .run()
+}
+
+#[derive(Default)]
+struct Animations {
+    toggled: bool,
+}
+
+#[derive(Debug, Clone)]
+enum Message {
+    Toggle(bool),
+}
+
+impl Animations {
+    fn update(&mut self, message: Message) -> Task<Message> {
+        match message {
+            Message::Toggle(t) => {
+                self.toggled = t;
+                Task::none()
+            }
+        }
+    }
+
+    fn view(&self) -> Element<Message> {
+        let main_text = iced::widget::text(
+            "You can find all widgets with default animations here.",
+        );
+        let toggle = Toggler::new(self.toggled)
+            .label("Toggle me!")
+            .on_toggle(Message::Toggle);
+        column![main_text, toggle]
+            .spacing(10)
+            .padding(50)
+            .max_width(800)
+            .into()
+    }
+
+    fn theme(&self) -> Theme {
+        Theme::Light
+    }
+}

widget/Cargo.toml

@@ -27,6 +27,7 @@ wgpu = ["iced_renderer/wgpu"]
 markdown = ["dep:pulldown-cmark", "dep:url"]
 highlighter = ["dep:iced_highlighter"]
 advanced = []
+animations = []
 
 [dependencies]
 iced_renderer.workspace = true