refactor: icon styling and headerbar icon styling

Headerbar icons are transparent when their window is not focused, but otherwise share the same style as icons with selection. This updates the icon styles to match figma when selected.

src/app/core.rs

@@ -6,6 +6,7 @@ use std::collections::HashMap;
 use crate::config::CosmicTk;
 use cosmic_config::CosmicConfigEntry;
 use cosmic_theme::ThemeMode;
+use iced::window;
 use iced_core::window::Id;
 use palette::Srgba;
 
@@ -57,6 +58,9 @@ pub struct Core {
     /// Scaling factor used by the application
     scale_factor: f32,
 
+    /// Window focus state
+    pub(super) focused_window: Option<window::Id>,
+
     pub(super) theme_sub_counter: u64,
     /// Last known system theme
     pub(super) system_theme: Theme,
@@ -136,6 +140,7 @@ impl Default for Core {
                 height: 0,
                 width: 0,
             },
+            focused_window: None,
             #[cfg(feature = "applet")]
             applet: crate::applet::Context::default(),
             #[cfg(feature = "single-instance")]
@@ -285,6 +290,12 @@ impl Core {
         )
     }
 
+    /// Get the current focused window if it exists
+    #[must_use]
+    pub fn focused_window(&self) -> Option<window::Id> {
+        self.focused_window.clone()
+    }
+
     /// Whether the application should use a dark theme, according to the system
     #[must_use]
     pub fn system_is_dark(&self) -> bool {

src/app/cosmic.rs

@@ -78,6 +78,10 @@ pub enum Message {
     ShowWindowMenu,
     #[cfg(feature = "xdg-portal")]
     DesktopSettings(crate::theme::portal::Desktop),
+    /// Window focus changed
+    Focus(window::Id),
+    /// Window focus lost
+    Unfocus(window::Id),
 }
 
 #[derive(Default)]
@@ -159,6 +163,10 @@ where
                 iced::Event::Window(id, window::Event::Closed) => {
                     return Some(Message::SurfaceClosed(id))
                 }
+                iced::Event::Window(id, window::Event::Focused) => return Some(Message::Focus(id)),
+                iced::Event::Window(id, window::Event::Unfocused) => {
+                    return Some(Message::Unfocus(id))
+                }
                 #[cfg(feature = "wayland")]
                 iced::Event::PlatformSpecific(PlatformSpecific::Wayland(event)) => match event {
                     wayland::Event::Window(WindowEvent::State(state), _surface, id) => {
@@ -557,6 +565,22 @@ impl<T: Application> Cosmic<T> {
             Message::ToolkitConfig(config) => {
                 self.app.core_mut().toolkit_config = config;
             }
+
+            Message::Focus(f) => {
+                self.app.core_mut().focused_window = Some(f);
+            }
+
+            Message::Unfocus(id) => {
+                let core = self.app.core_mut();
+                if core
+                    .focused_window
+                    .as_ref()
+                    .map(|cur| *cur == id)
+                    .unwrap_or_default()
+                {
+                    core.focused_window = None;
+                }
+            }
         }
 
         iced::Command::none()

src/app/mod.rs

@@ -642,6 +642,10 @@ impl<App: Application> ApplicationExt for App {
     fn view_main(&self) -> Element<Message<Self::Message>> {
         let core = self.core();
         let is_condensed = core.is_condensed();
+        let focused = core
+            .focused_window()
+            .map(|i| i == self.main_window_id())
+            .unwrap_or_default();
 
         let content_row = crate::widget::row::with_children({
             let mut widgets = Vec::with_capacity(2);
@@ -686,7 +690,7 @@ impl<App: Application> ApplicationExt for App {
             .push_maybe(if core.window.show_headerbar {
                 Some({
                     let mut header = crate::widget::header_bar()
-                        .window_id(self.main_window_id())
+                        .focused(focused)
                         .title(&core.window.header_title)
                         .on_drag(Message::Cosmic(cosmic::Message::Drag))
                         .on_close(Message::Cosmic(cosmic::Message::Close))