Merge branch 'master' into feature/test-recorder

src/daemon.rs

@@ -7,6 +7,7 @@ use crate::theme;
 use crate::window;
 use crate::{
     Element, Executor, Font, Preset, Result, Settings, Subscription, Task,
+    Theme,
 };
 
 use iced_debug as debug;
@@ -24,14 +25,14 @@ use std::borrow::Cow;
 ///
 /// [`exit`]: crate::exit
 pub fn daemon<State, Message, Theme, Renderer>(
-    boot: impl application::Boot<State, Message>,
-    update: impl application::Update<State, Message>,
-    view: impl for<'a> View<'a, State, Message, Theme, Renderer>,
+    boot: impl application::BootFn<State, Message>,
+    update: impl application::UpdateFn<State, Message>,
+    view: impl for<'a> ViewFn<'a, State, Message, Theme, Renderer>,
 ) -> Daemon<impl Program<State = State, Message = Message, Theme = Theme>>
 where
     State: 'static,
     Message: Send + 'static,
-    Theme: Default + theme::Base,
+    Theme: theme::Base,
     Renderer: program::Renderer,
 {
     use std::marker::PhantomData;
@@ -50,11 +51,11 @@ where
         for Instance<State, Message, Theme, Renderer, Boot, Update, View>
     where
         Message: Send + 'static,
-        Theme: Default + theme::Base,
+        Theme: theme::Base,
         Renderer: program::Renderer,
-        Boot: application::Boot<State, Message>,
-        Update: application::Update<State, Message>,
-        View: for<'a> self::View<'a, State, Message, Theme, Renderer>,
+        Boot: application::BootFn<State, Message>,
+        Update: application::UpdateFn<State, Message>,
+        View: for<'a> self::ViewFn<'a, State, Message, Theme, Renderer>,
     {
         type State = State;
         type Message = Message;
@@ -183,10 +184,10 @@ impl<P: Program> Daemon<P> {
         self
     }
 
-    /// Sets the [`Title`] of the [`Daemon`].
+    /// Sets the title of the [`Daemon`].
     pub fn title(
         self,
-        title: impl Title<P::State>,
+        title: impl TitleFn<P::State>,
     ) -> Daemon<
         impl Program<State = P::State, Message = P::Message, Theme = P::Theme>,
     > {
@@ -216,12 +217,14 @@ impl<P: Program> Daemon<P> {
     /// Sets the theme logic of the [`Daemon`].
     pub fn theme(
         self,
-        f: impl Fn(&P::State, window::Id) -> P::Theme,
+        f: impl ThemeFn<P::State, P::Theme>,
     ) -> Daemon<
         impl Program<State = P::State, Message = P::Message, Theme = P::Theme>,
     > {
         Daemon {
-            raw: program::with_theme(self.raw, f),
+            raw: program::with_theme(self.raw, move |state, window| {
+                f.theme(state, window)
+            }),
             settings: self.settings,
             presets: self.presets,
         }
@@ -244,7 +247,7 @@ impl<P: Program> Daemon<P> {
     /// Sets the scale factor of the [`Daemon`].
     pub fn scale_factor(
         self,
-        f: impl Fn(&P::State, window::Id) -> f64,
+        f: impl Fn(&P::State, window::Id) -> f32,
     ) -> Daemon<
         impl Program<State = P::State, Message = P::Message, Theme = P::Theme>,
     > {
@@ -338,7 +341,7 @@ impl<P: Program> Program for Daemon<P> {
         &self,
         state: &Self::State,
         window: iced_core::window::Id,
-    ) -> Self::Theme {
+    ) -> Option<Self::Theme> {
         debug::hot(|| self.raw.theme(state, window))
     }
 
@@ -346,7 +349,7 @@ impl<P: Program> Program for Daemon<P> {
         debug::hot(|| self.raw.style(state, theme))
     }
 
-    fn scale_factor(&self, state: &Self::State, window: window::Id) -> f64 {
+    fn scale_factor(&self, state: &Self::State, window: window::Id) -> f32 {
         debug::hot(|| self.raw.scale_factor(state, window))
     }
 
@@ -361,18 +364,18 @@ impl<P: Program> Program for Daemon<P> {
 /// any closure `Fn(&State, window::Id) -> String`.
 ///
 /// This trait allows the [`daemon`] builder to take any of them.
-pub trait Title<State> {
+pub trait TitleFn<State> {
     /// Produces the title of the [`Daemon`].
     fn title(&self, state: &State, window: window::Id) -> String;
 }
 
-impl<State> Title<State> for &'static str {
+impl<State> TitleFn<State> for &'static str {
     fn title(&self, _state: &State, _window: window::Id) -> String {
         self.to_string()
     }
 }
 
-impl<T, State> Title<State> for T
+impl<T, State> TitleFn<State> for T
 where
     T: Fn(&State, window::Id) -> String,
 {
@@ -385,7 +388,7 @@ where
 ///
 /// This trait allows the [`daemon`] builder to take any closure that
 /// returns any `Into<Element<'_, Message>>`.
-pub trait View<'a, State, Message, Theme, Renderer> {
+pub trait ViewFn<'a, State, Message, Theme, Renderer> {
     /// Produces the widget of the [`Daemon`].
     fn view(
         &self,
@@ -395,7 +398,7 @@ pub trait View<'a, State, Message, Theme, Renderer> {
 }
 
 impl<'a, T, State, Message, Theme, Renderer, Widget>
-    View<'a, State, Message, Theme, Renderer> for T
+    ViewFn<'a, State, Message, Theme, Renderer> for T
 where
     T: Fn(&'a State, window::Id) -> Widget,
     State: 'static,
@@ -409,3 +412,35 @@ where
         self(state, window).into()
     }
 }
+
+/// The theme logic of some [`Daemon`].
+///
+/// Any implementors of this trait can be provided as an argument to
+/// [`Daemon::theme`].
+///
+/// `iced` provides two implementors:
+/// - the built-in [`Theme`] itself
+/// - and any `Fn(&State, window::Id) -> impl Into<Option<Theme>>`.
+pub trait ThemeFn<State, Theme> {
+    /// Returns the theme of the [`Daemon`] for the current state and window.
+    ///
+    /// If `None` is returned, `iced` will try to use a theme that
+    /// matches the system color scheme.
+    fn theme(&self, state: &State, window: window::Id) -> Option<Theme>;
+}
+
+impl<State> ThemeFn<State, Theme> for Theme {
+    fn theme(&self, _state: &State, _window: window::Id) -> Option<Theme> {
+        Some(self.clone())
+    }
+}
+
+impl<F, T, State, Theme> ThemeFn<State, Theme> for F
+where
+    F: Fn(&State, window::Id) -> T,
+    T: Into<Option<Theme>>,
+{
+    fn theme(&self, state: &State, window: window::Id) -> Option<Theme> {
+        (self)(state, window).into()
+    }
+}