Convert Renderer::Theme to generic Widget type

runtime/src/multi_window/program.rs

@@ -12,6 +12,9 @@ pub trait Program: Sized {
     /// The type of __messages__ your [`Program`] will produce.
     type Message: std::fmt::Debug + Send;
 
+    /// The theme used to draw the [`Program`].
+    type Theme;
+
     /// Handles a __message__ and updates the state of the [`Program`].
     ///
     /// This is where you define your __update logic__. All the __messages__,
@@ -28,5 +31,5 @@ pub trait Program: Sized {
     fn view(
         &self,
         window: window::Id,
-    ) -> Element<'_, Self::Message, Self::Renderer>;
+    ) -> Element<'_, Self::Message, Self::Theme, Self::Renderer>;
 }

runtime/src/multi_window/state.rs

@@ -92,7 +92,7 @@ where
         bounds: Size,
         cursor: mouse::Cursor,
         renderer: &mut P::Renderer,
-        theme: &<P::Renderer as iced_core::Renderer>::Theme,
+        theme: &P::Theme,
         style: &renderer::Style,
         clipboard: &mut dyn Clipboard,
         debug: &mut Debug,
@@ -252,7 +252,7 @@ fn build_user_interfaces<'a, P: Program>(
     renderer: &mut P::Renderer,
     size: Size,
     debug: &mut Debug,
-) -> Vec<UserInterface<'a, P::Message, P::Renderer>> {
+) -> Vec<UserInterface<'a, P::Message, P::Theme, P::Renderer>> {
     caches
         .drain(..)
         .map(|cache| {
@@ -267,7 +267,7 @@ fn build_user_interface<'a, P: Program>(
     renderer: &mut P::Renderer,
     size: Size,
     debug: &mut Debug,
-) -> UserInterface<'a, P::Message, P::Renderer> {
+) -> UserInterface<'a, P::Message, P::Theme, P::Renderer> {
     debug.view_started();
     let view = program.view();
     debug.view_finished();

runtime/src/overlay/nested.rs

@@ -10,16 +10,18 @@ use crate::core::{
 
 /// An overlay container that displays nested overlays
 #[allow(missing_debug_implementations)]
-pub struct Nested<'a, Message, Renderer> {
-    overlay: overlay::Element<'a, Message, Renderer>,
+pub struct Nested<'a, Message, Theme, Renderer> {
+    overlay: overlay::Element<'a, Message, Theme, Renderer>,
 }
 
-impl<'a, Message, Renderer> Nested<'a, Message, Renderer>
+impl<'a, Message, Theme, Renderer> Nested<'a, Message, Theme, Renderer>
 where
     Renderer: renderer::Renderer,
 {
     /// Creates a nested overlay from the provided [`overlay::Element`]
-    pub fn new(element: overlay::Element<'a, Message, Renderer>) -> Self {
+    pub fn new(
+        element: overlay::Element<'a, Message, Theme, Renderer>,
+    ) -> Self {
         Self { overlay: element }
     }
 
@@ -38,8 +40,8 @@ where
         _position: Point,
         translation: Vector,
     ) -> layout::Node {
-        fn recurse<Message, Renderer>(
-            element: &mut overlay::Element<'_, Message, Renderer>,
+        fn recurse<Message, Theme, Renderer>(
+            element: &mut overlay::Element<'_, Message, Theme, Renderer>,
             renderer: &Renderer,
             bounds: Size,
             translation: Vector,
@@ -71,16 +73,16 @@ where
     pub fn draw(
         &mut self,
         renderer: &mut Renderer,
-        theme: &<Renderer as renderer::Renderer>::Theme,
+        theme: &Theme,
         style: &renderer::Style,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
     ) {
-        fn recurse<Message, Renderer>(
-            element: &mut overlay::Element<'_, Message, Renderer>,
+        fn recurse<Message, Theme, Renderer>(
+            element: &mut overlay::Element<'_, Message, Theme, Renderer>,
             layout: Layout<'_>,
             renderer: &mut Renderer,
-            theme: &<Renderer as renderer::Renderer>::Theme,
+            theme: &Theme,
             style: &renderer::Style,
             cursor: mouse::Cursor,
         ) where
@@ -144,8 +146,8 @@ where
         renderer: &Renderer,
         operation: &mut dyn widget::Operation<Message>,
     ) {
-        fn recurse<Message, Renderer>(
-            element: &mut overlay::Element<'_, Message, Renderer>,
+        fn recurse<Message, Theme, Renderer>(
+            element: &mut overlay::Element<'_, Message, Theme, Renderer>,
             layout: Layout<'_>,
             renderer: &Renderer,
             operation: &mut dyn widget::Operation<Message>,
@@ -178,8 +180,8 @@ where
         clipboard: &mut dyn Clipboard,
         shell: &mut Shell<'_, Message>,
     ) -> event::Status {
-        fn recurse<Message, Renderer>(
-            element: &mut overlay::Element<'_, Message, Renderer>,
+        fn recurse<Message, Theme, Renderer>(
+            element: &mut overlay::Element<'_, Message, Theme, Renderer>,
             layout: Layout<'_>,
             event: Event,
             cursor: mouse::Cursor,
@@ -267,8 +269,8 @@ where
         viewport: &Rectangle,
         renderer: &Renderer,
     ) -> mouse::Interaction {
-        fn recurse<Message, Renderer>(
-            element: &mut overlay::Element<'_, Message, Renderer>,
+        fn recurse<Message, Theme, Renderer>(
+            element: &mut overlay::Element<'_, Message, Theme, Renderer>,
             layout: Layout<'_>,
             cursor: mouse::Cursor,
             viewport: &Rectangle,
@@ -318,8 +320,8 @@ where
         renderer: &Renderer,
         cursor_position: Point,
     ) -> bool {
-        fn recurse<Message, Renderer>(
-            element: &mut overlay::Element<'_, Message, Renderer>,
+        fn recurse<Message, Theme, Renderer>(
+            element: &mut overlay::Element<'_, Message, Theme, Renderer>,
             layout: Layout<'_>,
             renderer: &Renderer,
             cursor_position: Point,

runtime/src/program.rs

@@ -13,6 +13,9 @@ pub trait Program: Sized {
     /// The graphics backend to use to draw the [`Program`].
     type Renderer: Renderer + text::Renderer;
 
+    /// The theme used to draw the [`Program`].
+    type Theme;
+
     /// The type of __messages__ your [`Program`] will produce.
     type Message: std::fmt::Debug + Send;
 
@@ -29,5 +32,5 @@ pub trait Program: Sized {
     /// Returns the widgets to display in the [`Program`].
     ///
     /// These widgets can produce __messages__ based on user interaction.
-    fn view(&self) -> Element<'_, Self::Message, Self::Renderer>;
+    fn view(&self) -> Element<'_, Self::Message, Self::Theme, Self::Renderer>;
 }

runtime/src/program/state.rs

@@ -91,7 +91,7 @@ where
         bounds: Size,
         cursor: mouse::Cursor,
         renderer: &mut P::Renderer,
-        theme: &<P::Renderer as iced_core::Renderer>::Theme,
+        theme: &P::Theme,
         style: &renderer::Style,
         clipboard: &mut dyn Clipboard,
         debug: &mut Debug,
@@ -219,7 +219,7 @@ fn build_user_interface<'a, P: Program>(
     renderer: &mut P::Renderer,
     size: Size,
     debug: &mut Debug,
-) -> UserInterface<'a, P::Message, P::Renderer> {
+) -> UserInterface<'a, P::Message, P::Theme, P::Renderer> {
     debug.view_started();
     let view = program.view();
     debug.view_finished();

runtime/src/user_interface.rs

@@ -23,15 +23,15 @@ use crate::overlay;
 ///
 /// [`integration`]: https://github.com/iced-rs/iced/tree/0.10/examples/integration
 #[allow(missing_debug_implementations)]
-pub struct UserInterface<'a, Message, Renderer> {
-    root: Element<'a, Message, Renderer>,
+pub struct UserInterface<'a, Message, Theme, Renderer> {
+    root: Element<'a, Message, Theme, Renderer>,
     base: layout::Node,
     state: widget::Tree,
     overlay: Option<layout::Node>,
     bounds: Size,
 }
 
-impl<'a, Message, Renderer> UserInterface<'a, Message, Renderer>
+impl<'a, Message, Theme, Renderer> UserInterface<'a, Message, Theme, Renderer>
 where
     Renderer: crate::core::Renderer,
 {
@@ -54,7 +54,7 @@ where
     /// #
     /// # impl Counter {
     /// #     pub fn new() -> Self { Counter }
-    /// #     pub fn view(&self) -> iced_core::Element<(), Renderer> { unimplemented!() }
+    /// #     pub fn view(&self) -> iced_core::Element<(), (), Renderer> { unimplemented!() }
     /// #     pub fn update(&mut self, _: ()) {}
     /// # }
     /// use iced_runtime::core::Size;
@@ -86,7 +86,7 @@ where
     ///     cache = user_interface.into_cache();
     /// }
     /// ```
-    pub fn build<E: Into<Element<'a, Message, Renderer>>>(
+    pub fn build<E: Into<Element<'a, Message, Theme, Renderer>>>(
         root: E,
         bounds: Size,
         cache: Cache,
@@ -130,7 +130,7 @@ where
     /// #
     /// # impl Counter {
     /// #     pub fn new() -> Self { Counter }
-    /// #     pub fn view(&self) -> iced_core::Element<(), Renderer> { unimplemented!() }
+    /// #     pub fn view(&self) -> iced_core::Element<(), (), Renderer> { unimplemented!() }
     /// #     pub fn update(&mut self, _: ()) {}
     /// # }
     /// use iced_runtime::core::clipboard;
@@ -384,7 +384,7 @@ where
     /// #
     /// # impl Counter {
     /// #     pub fn new() -> Self { Counter }
-    /// #     pub fn view(&self) -> Element<(), Renderer> { unimplemented!() }
+    /// #     pub fn view(&self) -> Element<(), (), Renderer> { unimplemented!() }
     /// #     pub fn update(&mut self, _: ()) {}
     /// # }
     /// use iced_runtime::core::clipboard;
@@ -439,7 +439,7 @@ where
     pub fn draw(
         &mut self,
         renderer: &mut Renderer,
-        theme: &Renderer::Theme,
+        theme: &Theme,
         style: &renderer::Style,
         cursor: mouse::Cursor,
     ) -> mouse::Interaction {