Making all easing functions themable

CHANGELOG.md

@@ -7,6 +7,24 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 <!-- markdownlint-disable no-duplicate-heading -->
 
+## Unreleased
+
+### Fixed
+
+- `Collapse`, `OverlayLayer`, and `Progress` all honor the theme components
+  `EasingIn` and `EasingOut` rather than hard-coded easing functions.
+
+### Added
+
+- `ComponentProbe<T>` is a new widget that allows reading a
+  `ComponentDefinition` value from the theme at runtime through a
+  `Dynamic<T::ComponentType>`. For example, a `ComponentProbe<TextSize>` will
+  provide access to a `Dynamic<Dimension>`. Previously this required creating a
+  custom widget to access the runtime theme information.
+
+  `ContextFreeComponent::probe()` and `ContextFreeComponent::probe_wrapping()`
+  provide an easy interface for creating probes from components.
+
 ## v0.4.0 (2024-08-20)
 
 ### Breaking Changes

src/styles.rs

@@ -25,7 +25,9 @@ use crate::context::{Trackable, WidgetContext};
 use crate::names::Name;
 use crate::utils::Lazy;
 use crate::value::{Dynamic, IntoValue, Source, Value};
+use crate::widget::MakeWidget;
 use crate::widgets::input::CowString;
+use crate::widgets::ComponentProbe;
 
 #[macro_use]
 pub mod components;
@@ -1135,6 +1137,25 @@ pub trait ComponentDefinition: NamedComponent {
     fn default_value(&self, context: &WidgetContext<'_>) -> Self::ComponentType;
 }
 
+/// A [`ComponentDefinition`] that can provide a default value without access to
+/// a runtime context.
+pub trait ContextFreeComponent: ComponentDefinition {
+    /// Returns the default value for this component.
+    fn default(&self) -> Self::ComponentType;
+
+    /// Returns a new probe that provides access to the runtime value of this
+    /// component.
+    fn probe(self) -> ComponentProbe<Self> {
+        ComponentProbe::default_for(self)
+    }
+
+    /// Returns a new probe wrapping `child` that provides access to the runtime
+    /// value of this component.
+    fn probe_wrapping(self, child: impl MakeWidget) -> ComponentProbe<Self> {
+        ComponentProbe::default_wrapping(self, child)
+    }
+}
+
 /// Describes whether a type should invalidate a widget.
 pub trait RequireInvalidation {
     /// Cushy tracks two different states:

src/styles/components.rs

@@ -62,6 +62,8 @@ macro_rules! define_components {
 
                 define_components!($type, $($($default)*)?);
             }
+
+            define_components!(default $component $type, $($($default)*)?);
         };
 
     )*)*};
@@ -90,6 +92,29 @@ macro_rules! define_components {
     ($type:ty, $($expr:tt)+) => {
         define_components!($type, |_context| $($expr)*);
     };
+    (default $component:ident $type:ty, . $($path:tt)*) => {
+
+    };
+    (default $component:ident $type:ty, |$context:ident| $($expr:tt)*) => {
+    };
+    (default $component:ident $type:ty, @$path:path) => {
+    };
+    (default $component:ident $type:ty, contrasting!($bg:ident, $($fg:ident),+ $(,)?)) => {
+    };
+    (default $component:ident $type:ty, ) => {
+        impl $crate::styles::ContextFreeComponent for $component {
+            fn default(&self) -> Self::ComponentType {
+                <$type>::default()
+            }
+        }
+    };
+    (default $component:ident $type:ty, $($expr:tt)+) => {
+        impl $crate::styles::ContextFreeComponent for $component {
+            fn default(&self) -> Self::ComponentType {
+                $($expr)*
+            }
+        }
+    };
 }
 
 define_components! {
@@ -204,7 +229,7 @@ define_components! {
         LayoutOrder(VisualOrder, "visual_order", VisualOrder::left_to_right())
         /// The set of controls to allow focusing via tab key and initial focus
         /// selection.
-        AutoFocusableControls(FocusableWidgets, "focus", FocusableWidgets::default())
+        AutoFocusableControls(FocusableWidgets, "focus")
         /// A [`Color`] to be used as the background color of a widget.
         WidgetBackground(Color, "widget_backgrond_color", Color::CLEAR_WHITE)
         /// A [`Color`] to be used to accent a widget.

src/widgets.rs

@@ -6,6 +6,7 @@ mod canvas;
 pub mod checkbox;
 mod collapse;
 pub mod color;
+mod component_probe;
 pub mod container;
 mod custom;
 mod data;
@@ -40,6 +41,7 @@ pub use self::button::Button;
 pub use self::canvas::Canvas;
 pub use self::checkbox::Checkbox;
 pub use self::collapse::Collapse;
+pub use self::component_probe::ComponentProbe;
 pub use self::container::Container;
 pub use self::custom::Custom;
 pub use self::data::Data;

src/widgets/collapse.rs

@@ -3,9 +3,9 @@ use std::time::Duration;
 use figures::units::Px;
 use figures::{Size, Zero};
 
-use crate::animation::easings::{EaseInQuadradic, EaseOutQuadradic};
-use crate::animation::{AnimationHandle, AnimationTarget, EasingFunction, Spawn};
+use crate::animation::{AnimationHandle, AnimationTarget, Spawn};
 use crate::context::LayoutContext;
+use crate::styles::components::{EasingIn, EasingOut};
 use crate::value::{Dynamic, IntoDynamic, Source};
 use crate::widget::{MakeWidget, WidgetRef, WrappedLayout, WrapperWidget};
 use crate::ConstraintLimit;
@@ -53,9 +53,9 @@ impl Collapse {
 
     fn note_child_size(&mut self, size: Px, context: &mut LayoutContext<'_, '_, '_, '_>) {
         let (easing, target) = if self.collapse.get_tracking_invalidate(context) {
-            (EasingFunction::from(EaseOutQuadradic), Px::ZERO)
+            (context.get(&EasingOut), Px::ZERO)
         } else {
-            (EasingFunction::from(EaseInQuadradic), size)
+            (context.get(&EasingIn), size)
         };
         match &self.collapse_animation {
             Some(state) if state.target == target => {}

src/widgets/component_probe.rs

@@ -0,0 +1,96 @@
+use std::fmt::Debug;
+
+use super::Space;
+use crate::styles::{ComponentDefinition, ContextFreeComponent};
+use crate::value::{Destination, Dynamic};
+use crate::widget::{MakeWidget, WidgetRef, WrapperWidget};
+
+/// A widget that provides access to a [`ComponentDefinition`]'s value through a
+/// [`Dynamic`].
+///
+/// This widget enables access to runtime values provided by the theme without
+/// creating a custom widget. After creating a probe, [`value()`](Self::value)
+/// can be used to observe and use the value.
+///
+/// The theme information retrieved will be the effective theme at the location
+/// the probe is inserted in the widget hierarchy.
+#[derive(Debug)]
+pub struct ComponentProbe<Component>
+where
+    Component: ComponentDefinition,
+{
+    component: Component,
+    probed: Dynamic<Component::ComponentType>,
+    child: WidgetRef,
+}
+
+impl<Component> ComponentProbe<Component>
+where
+    Component: ComponentDefinition,
+{
+    /// Returns a new probe that provides access to the runtime value of
+    /// `Component`.
+    ///
+    /// The initial contents of the dynamic will be `initial_value`.
+    pub fn new(component: Component, initial_value: Component::ComponentType) -> Self {
+        Self::new_wrapping(component, initial_value, Space::clear())
+    }
+
+    /// Returns a new probe wrapping `child` that provides access to the runtime
+    /// value of this component.
+    ///
+    /// The initial contents of the dynamic will be `initial_value`.
+    pub fn new_wrapping(
+        component: Component,
+        initial_value: Component::ComponentType,
+        child: impl MakeWidget,
+    ) -> Self {
+        Self {
+            component,
+            probed: Dynamic::new(initial_value),
+            child: WidgetRef::new(child),
+        }
+    }
+
+    /// Returns a new probe that provides access to the runtime value of
+    /// `Component`.
+    pub fn default_for(component: Component) -> Self
+    where
+        Component: ContextFreeComponent,
+    {
+        let default = component.default();
+        Self::new(component, default)
+    }
+
+    /// Returns a new probe wrapping `child` that provides access to the runtime
+    /// value of this component.
+    pub fn default_wrapping(component: Component, child: impl MakeWidget) -> Self
+    where
+        Component: ContextFreeComponent,
+    {
+        let default = component.default();
+        Self::new_wrapping(component, default, child)
+    }
+
+    /// Returns the dynamic that contains the component's current value.
+    ///
+    /// This dynamic's contents will be updated whenever this probe is
+    /// invalidated.
+    pub const fn value(&self) -> &Dynamic<Component::ComponentType> {
+        &self.probed
+    }
+}
+
+impl<Component> WrapperWidget for ComponentProbe<Component>
+where
+    Component: ComponentDefinition + Debug + Send + 'static,
+    Component::ComponentType: PartialEq + Debug + Send + 'static,
+{
+    fn child_mut(&mut self) -> &mut crate::widget::WidgetRef {
+        &mut self.child
+    }
+
+    fn redraw_foreground(&mut self, context: &mut crate::context::GraphicsContext<'_, '_, '_, '_>) {
+        self.probed.set(context.get(&self.component));
+    }
+}

src/widgets/layers.rs

@@ -6,14 +6,15 @@ use std::time::Duration;
 
 use alot::{LotId, OrderedLots};
 use cushy::widget::{RootBehavior, WidgetInstance};
+use easing_function::EasingFunction;
 use figures::units::{Lp, Px, UPx};
 use figures::{IntoSigned, IntoUnsigned, Point, Rect, Size, Zero};
 use intentional::Assert;
 use parking_lot::Mutex;
 
-use crate::animation::easings::EaseOutQuadradic;
 use crate::animation::{AnimationHandle, AnimationTarget, IntoAnimate, Spawn, ZeroToOne};
 use crate::context::{AsEventContext, EventContext, GraphicsContext, LayoutContext, Trackable};
+use crate::styles::components::EasingIn;
 use crate::value::{Destination, Dynamic, DynamicGuard, IntoValue, Source, Value};
 use crate::widget::{
     Callback, MakeWidget, MountedChildren, MountedWidget, Widget, WidgetId, WidgetList, WidgetRef,
@@ -139,6 +140,7 @@ impl Widget for Layers {
 #[derive(Debug, Clone, Default)]
 pub struct OverlayLayer {
     state: Dynamic<OverlayState>,
+    easing: Dynamic<EasingFunction>,
 }
 
 impl OverlayLayer {
@@ -189,6 +191,7 @@ impl OverlayLayer {
 
 impl Widget for OverlayLayer {
     fn redraw(&mut self, context: &mut GraphicsContext<'_, '_, '_, '_>) {
+        self.easing.set(context.get(&EasingIn));
         let state = self.state.lock();
 
         for child in &state.overlays {
@@ -691,7 +694,7 @@ impl OverlayBuilder<'_> {
             .opacity
             .transition_to(ZeroToOne::ONE)
             .over(Duration::from_millis(250))
-            .with_easing(EaseOutQuadradic)
+            .with_easing(self.overlay.easing.get())
             .launch();
     }
 }

src/widgets/progress.rs

@@ -3,15 +3,17 @@
 use std::ops::RangeInclusive;
 use std::time::Duration;
 
+use easing_function::EasingFunction;
 use figures::units::Px;
 use figures::{Angle, Point, Ranged, ScreenScale, Size, Zero};
 use kludgine::shapes::{Path, StrokeOptions};
 use kludgine::Color;
 
-use crate::animation::easings::{EaseInQuadradic, EaseOutQuadradic};
 use crate::animation::{
     AnimationHandle, AnimationTarget, IntoAnimate, PercentBetween, Spawn, ZeroToOne,
 };
+use crate::styles::components::{EasingIn, EasingOut};
+use crate::styles::ContextFreeComponent;
 use crate::value::{Destination, Dynamic, IntoReadOnly, IntoReader, MapEach, ReadOnly, Source};
 use crate::widget::{MakeWidget, MakeWidgetWithTag, Widget, WidgetInstance};
 use crate::widgets::slider::{InactiveTrackColor, Slidable, TrackColor, TrackSize};
@@ -91,29 +93,41 @@ impl MakeWidgetWithTag for ProgressBar {
             )
         };
 
+        let ease_in_probe = EasingIn.probe_wrapping(slider);
+        let ease_in = ease_in_probe.value().clone();
+        let ease_out_probe = EasingOut.probe_wrapping(ease_in_probe);
+        let ease_out = ease_out_probe.value().clone();
         update_progress_bar(
             self.progress.get(),
             &mut indeterminant_animation,
             &start,
             &end,
             degree_offset.as_ref(),
+            &ease_in,
+            &ease_out,
         );
 
         match self.progress {
             ReadOnly::Reader(progress) => {
-                let callback = progress.for_each(move |progress| {
-                    update_progress_bar(
-                        *progress,
-                        &mut indeterminant_animation,
-                        &start,
-                        &end,
-                        degree_offset.as_ref(),
-                    );
+                let callback = progress.for_each({
+                    let ease_in = ease_in.clone();
+                    let ease_out = ease_out.clone();
+                    move |progress| {
+                        update_progress_bar(
+                            *progress,
+                            &mut indeterminant_animation,
+                            &start,
+                            &end,
+                            degree_offset.as_ref(),
+                            &ease_in,
+                            &ease_out,
+                        );
+                    }
                 });
-                Data::new_wrapping((callback, progress), slider).make_widget()
+                Data::new_wrapping((callback, progress), ease_out_probe).make_widget()
             }
             ReadOnly::Constant(_) => {
-                Data::new_wrapping(indeterminant_animation, slider).make_widget()
+                Data::new_wrapping(indeterminant_animation, ease_out_probe).make_widget()
             }
         }
     }
@@ -131,10 +145,14 @@ fn update_progress_bar(
     start: &Dynamic<ZeroToOne>,
     end: &Dynamic<ZeroToOne>,
     degree_offset: Option<&Dynamic<Angle>>,
+    ease_in: &Dynamic<EasingFunction>,
+    ease_out: &Dynamic<EasingFunction>,
 ) {
     match progress {
         Progress::Indeterminant => {
             if indeterminant_animation.is_none() {
+                let ease_in = ease_in.get();
+                let ease_out = ease_out.get();
                 *indeterminant_animation = Some(IndeterminantAnimations {
                     _primary: (
                         start
@@ -145,25 +163,25 @@ fn update_progress_bar(
                                 start
                                     .transition_to(ZeroToOne::new(0.33))
                                     .over(Duration::from_millis(500))
-                                    .with_easing(EaseInQuadradic),
+                                    .with_easing(ease_in.clone()),
                             )
                             .and_then(
                                 start
                                     .transition_to(ZeroToOne::new(1.0))
                                     .over(Duration::from_millis(500))
-                                    .with_easing(EaseOutQuadradic),
+                                    .with_easing(ease_out.clone()),
                             ),
                         end.transition_to(ZeroToOne::ZERO)
                             .immediately()
                             .and_then(
                                 end.transition_to(ZeroToOne::new(0.75))
                                     .over(Duration::from_millis(500))
-                                    .with_easing(EaseInQuadradic),
+                                    .with_easing(ease_in),
                             )
                             .and_then(
                                 end.transition_to(ZeroToOne::ONE)
                                     .over(Duration::from_millis(250))
-                                    .with_easing(EaseOutQuadradic),
+                                    .with_easing(ease_out.clone()),
                             ),
                     )
                         .cycle()