feat: add set_badge_count for Linux, iOS; set_badge_label for Macos; set_overlay_icon for Windows

.changes/badge_count.md

@@ -0,0 +1,5 @@
+---
+"tao": patch
+---
+
+Add **set_badge_count** for Linux; **set_badge_label** for Macos; **set_overlay_icon** for Windows

examples/overlay.rs

@@ -0,0 +1,79 @@
+// Copyright 2014-2021 The winit contributors
+// Copyright 2021-2023 Tauri Programme within The Commons Conservancy
+// SPDX-License-Identifier: Apache-2.0
+
+use std::env::current_dir;
+use tao::{
+  event::{ElementState, Event, KeyEvent, WindowEvent}, event_loop::{ControlFlow, EventLoop}, keyboard::{Key, ModifiersState}, platform::windows::IconExtWindows, window::WindowBuilder
+};
+
+#[allow(clippy::single_match)]
+fn main() {
+  env_logger::init();
+  let event_loop = EventLoop::new();
+
+  let window = WindowBuilder::new().build(&event_loop).unwrap();
+
+  let mut modifiers = ModifiersState::default();
+
+  eprintln!("Key mappings:");
+  #[cfg(windows)]
+  eprintln!("  [any key]: Show the Overlay Icon");
+  #[cfg(not(windows))]
+  eprintln!("  [1-5]: Show a Badge count");
+  eprintln!("  Ctrl+1: Clear");
+
+  event_loop.run(move |event, _, control_flow| {
+    *control_flow = ControlFlow::Wait;
+
+    match event {
+      Event::WindowEvent {
+        event: WindowEvent::CloseRequested,
+        ..
+      } => *control_flow = ControlFlow::Exit,
+      Event::WindowEvent { event, .. } => match event {
+        WindowEvent::ModifiersChanged(new_state) => {
+          modifiers = new_state;
+        }
+        WindowEvent::KeyboardInput {
+          event:
+            KeyEvent {
+              logical_key: Key::Character(key_str),
+              state: ElementState::Released,
+              ..
+            },
+          ..
+        } => {
+          #[cfg(not(windows))]
+          if modifiers.is_empty() {
+            window.set_badge_count(Some(match key_str {
+              "1" => 1,
+              "2" => 2,
+              "3" => 3,
+              "4" => 4,
+              "5" => 5,
+              _ => 20
+            }), None);
+          } else if modifiers.control_key() && key_str == "1" {
+            window.set_badge_count(None, None);
+          }
+
+          #[cfg(windows)]
+          {
+            use tao::{window::Icon, platform::windows::WindowExtWindows};
+            if modifiers.is_empty() {
+              let mut path = current_dir().unwrap();
+              path.push("./examples/icon.ico");
+
+              window.set_overlay_icon(Some(Icon::from_path(path, None).unwrap()));
+            } else if modifiers.control_key() && key_str == "1" {
+              window.set_overlay_icon(None);
+            }
+          }
+        }
+        _ => {}
+      },
+      _ => {}
+    }
+  });
+}

src/platform/macos.rs

@@ -84,6 +84,9 @@ pub trait WindowExtMacOS {
   ///
   /// <https://developer.apple.com/documentation/appkit/nswindow/1419167-titlebarappearstransparent>
   fn set_titlebar_transparent(&self, transparent: bool);
+
+  /// Sets the badge label on the taskbar
+  fn set_badge_label(&self, label: Option<String>);
 }
 
 impl WindowExtMacOS for Window {
@@ -161,6 +164,11 @@ impl WindowExtMacOS for Window {
   fn set_titlebar_transparent(&self, transparent: bool) {
     self.window.set_titlebar_transparent(transparent);
   }
+
+  #[inline]
+  fn set_badge_label(&self, label: Option<String>) {
+    self.window.set_badge_label(label);
+  }
 }
 
 /// Corresponds to `NSApplicationActivationPolicy`.

src/platform/unix.rs

@@ -78,6 +78,8 @@ pub trait WindowExtUnix {
 
   /// Whether to show the window icon in the taskbar or not.
   fn set_skip_taskbar(&self, skip: bool) -> Result<(), ExternalError>;
+
+  fn set_badge_count(&self, count: Option<i64>, desktop_filename: Option<String>);
 }
 
 impl WindowExtUnix for Window {
@@ -100,6 +102,10 @@ impl WindowExtUnix for Window {
     let window = UnixWindow::new_from_gtk_window(&event_loop_window_target.p, window)?;
     Ok(Window { window: window })
   }
+
+  fn set_badge_count(&self, count: Option<i64>, desktop_filename: Option<String>) {
+    self.window.set_badge_count(count, desktop_filename);
+  }
 }
 
 pub trait WindowBuilderExtUnix {

src/platform/windows.rs

@@ -159,6 +159,9 @@ pub trait WindowExtWindows {
   /// This sets `ICON_BIG`. A good ceiling here is 256x256.
   fn set_taskbar_icon(&self, taskbar_icon: Option<Icon>);
 
+  /// This sets the overlay icon
+  fn set_overlay_icon(&self, icon: Option<Icon>);
+
   /// Returns the current window theme.
   fn theme(&self) -> Theme;
 
@@ -238,6 +241,11 @@ impl WindowExtWindows for Window {
   fn set_rtl(&self, rtl: bool) {
     self.window.set_rtl(rtl)
   }
+
+  #[inline]
+  fn set_overlay_icon(&self, icon: Option<Icon>) {
+    self.window.set_overlay_icon(icon);
+  }
 }
 
 /// Additional methods on `WindowBuilder` that are specific to Windows.

src/platform_impl/linux/event_loop.rs

@@ -160,6 +160,16 @@ impl<T> EventLoopWindowTarget<T> {
     }
   }
 
+  #[inline]
+  pub fn set_badge_count(&self, count: Option<i64>, desktop_filename: Option<String>) {
+    if let Err(e) = self
+      .window_requests_tx
+      .send((WindowId::dummy(), WindowRequest::BadgeCount(count, desktop_filename)))
+    {
+      log::warn!("Fail to send update progress bar request: {e}");
+    }
+  }
+
   #[inline]
   pub fn set_theme(&self, theme: Option<Theme>) {
     if let Err(e) = self
@@ -432,6 +442,7 @@ impl<T: 'static> EventLoop<T> {
             };
           }
           WindowRequest::ProgressBarState(_) => unreachable!(),
+          WindowRequest::BadgeCount(_, _) => unreachable!(),
           WindowRequest::SetTheme(_) => unreachable!(),
           WindowRequest::WireUpEvents {
             transparent,
@@ -921,6 +932,9 @@ impl<T: 'static> EventLoop<T> {
           WindowRequest::ProgressBarState(state) => {
             taskbar.update(state);
           }
+          WindowRequest::BadgeCount(count, desktop_filename) => {
+            taskbar.update_count(count, desktop_filename);
+          }
           WindowRequest::SetTheme(theme) => {
             if let Some(settings) = Settings::default() {
               match theme {

src/platform_impl/linux/taskbar.rs

@@ -12,6 +12,9 @@ struct UnityLib {
   unity_launcher_entry_set_progress: unsafe extern "C" fn(entry: *const isize, value: f64) -> i32,
   unity_launcher_entry_set_progress_visible:
     unsafe extern "C" fn(entry: *const isize, value: i32) -> i32,
+  unity_launcher_entry_set_count: unsafe extern "C" fn(entry: *const isize, value: i64) -> i32,
+  unity_launcher_entry_set_count_visible:
+    unsafe extern "C" fn(entry: *const isize, value: bool) -> bool,
 }
 
 pub struct TaskbarIndicator {
@@ -120,4 +123,39 @@ impl TaskbarIndicator {
       }
     }
   }
+
+  pub fn update_count(&mut self, count: Option<i64>, desktop_filename: Option<String>) {
+    if let Some(uri) = desktop_filename {
+      self.desktop_filename = Some(uri);
+    }
+
+    self.ensure_lib_load();
+
+    if !self.is_unity_running() {
+      return;
+    }
+
+    if let Some(uri) = &self.desktop_filename {
+      self.desktop_filename_c_str = Some(CString::new(uri.as_str()).unwrap_or_default());
+    }
+
+    if self.unity_entry.is_none() {
+      self.ensure_entry_load();
+    }
+
+    if let Some(unity_lib) = &self.unity_lib {
+      if let Some(unity_entry) = &self.unity_entry {
+        // Sets count
+        if let Some(count) = count {
+          unsafe { (unity_lib.unity_launcher_entry_set_count)(*unity_entry, count) };
+          unsafe { (unity_lib.unity_launcher_entry_set_count_visible)(*unity_entry, true) };
+        }
+        // removes the count
+        else {
+          unsafe { (unity_lib.unity_launcher_entry_set_count)(*unity_entry, 0) };
+          unsafe { (unity_lib.unity_launcher_entry_set_count_visible)(*unity_entry, false) };
+        }
+      }
+    }
+  }
 }

src/platform_impl/linux/window.rs

@@ -1006,6 +1006,15 @@ impl Window {
     }
   }
 
+  pub fn set_badge_count(&self, count: Option<i64>, desktop_filename: Option<String>) {
+    if let Err(e) = self
+      .window_requests_tx
+      .send((WindowId::dummy(), WindowRequest::BadgeCount(count, desktop_filename)))
+    {
+      log::warn!("Fail to send update badge count request: {}", e);
+    }
+  }
+
   pub fn theme(&self) -> Theme {
     if let Some(theme) = *self.preferred_theme.borrow() {
       return theme;
@@ -1068,6 +1077,7 @@ pub enum WindowRequest {
   },
   SetVisibleOnAllWorkspaces(bool),
   ProgressBarState(ProgressBarState),
+  BadgeCount(Option<i64>, Option<String>),
   SetTheme(Option<Theme>),
   BackgroundColor(CssProvider, Option<RGBA>),
 }

src/platform_impl/macos/badge.rs

@@ -0,0 +1,12 @@
+use cocoa::{appkit::NSApp, base::nil, foundation::NSString};
+
+pub fn set_badge_label(label: Option<String>) {
+  unsafe {
+    let label = match label {
+      None => nil,
+      Some(label) => NSString::alloc(nil).init_str(&label)
+    };
+    let dock_tile: cocoa::base::id = msg_send![NSApp(), dockTile];
+    let _: cocoa::base::id = msg_send![dock_tile, setBadgeLabel: label];
+  }
+}

src/platform_impl/macos/event_loop.rs

@@ -38,6 +38,7 @@ use crate::{
       util::{self, IdRef},
     },
     set_progress_indicator,
+    set_badge_label
   },
   window::{ProgressBarState, Theme},
 };
@@ -125,6 +126,16 @@ impl<T: 'static> EventLoopWindowTarget<T> {
     set_progress_indicator(progress);
   }
 
+  #[inline]
+  pub fn set_badge_count(&self, count: Option<i64>, _desktop_filename: Option<String>) {
+    set_badge_label(count.map(|c| c.to_string()));
+  }
+
+  #[inline]
+  pub fn set_badge_label(&self, label: Option<String>) {
+    set_badge_label(label);
+  }
+
   #[inline]
   pub fn set_theme(&self, theme: Option<Theme>) {
     set_ns_theme(theme)

src/platform_impl/macos/mod.rs

@@ -15,6 +15,7 @@ mod keycode;
 mod monitor;
 mod observer;
 mod progress_bar;
+mod badge;
 mod util;
 mod view;
 mod window;

src/platform_impl/macos/window.rs

@@ -32,6 +32,7 @@ use crate::{
       OsError,
     },
     set_progress_indicator,
+    set_badge_label
   },
   window::{
     CursorIcon, Fullscreen, ProgressBarState, ResizeDirection, Theme, UserAttentionType,
@@ -1498,6 +1499,10 @@ impl UnownedWindow {
   pub fn set_progress_bar(&self, progress: ProgressBarState) {
     set_progress_indicator(progress);
   }
+
+  pub fn set_badge_label(&self, label: Option<String>) {
+    set_badge_label(label);
+  }
 }
 
 impl WindowExtMacOS for UnownedWindow {

src/platform_impl/windows/window.rs

@@ -1023,6 +1023,30 @@ impl Window {
     }
   }
 
+  #[inline]
+  pub fn set_overlay_icon(&self, icon: Option<Icon>) {
+    let taskbar: ITaskbarList = unsafe {
+      CoCreateInstance(&TaskbarList, None, CLSCTX_SERVER).unwrap()
+    };
+
+    let Some(Icon { inner }) = icon else {
+      unsafe {
+        taskbar
+          .SetOverlayIcon(self.window.0, None, None)
+          .unwrap();
+      }
+      return;
+    };
+
+    let icon = inner.as_raw_handle();
+
+    unsafe {
+      taskbar
+        .SetOverlayIcon(self.window.0, icon, None)
+        .unwrap();
+    }
+  }
+
   #[inline]
   pub fn set_undecorated_shadow(&self, shadow: bool) {
     let window = self.window.clone();

src/window.rs

@@ -1099,7 +1099,7 @@ impl Window {
   ///
   /// ## Platform-specific
   ///
-  /// - **Linux / macOS**: Progress bar is app-wide and not specific to this window. Only supported desktop environments with `libunity` (e.g. GNOME).
+  /// - **Linux / macOS**: Unlike windows, progress bar is app-wide and not specific to this window. Only supported desktop environments with `libunity` (e.g. GNOME).
   /// - **iOS / Android:** Unsupported.
   #[inline]
   pub fn set_progress_bar(&self, _progress: ProgressBarState) {
@@ -1115,6 +1115,31 @@ impl Window {
     self.window.set_progress_bar(_progress)
   }
 
+  /// Sets the badge count on the taskbar
+  ///
+  /// ## Implementation Details
+  /// - _desktop_filename is for linux ONLY!
+  /// 
+  /// ## Platform-specific
+  ///
+  /// - **Windows**: Windows allows to set an arbitrary .ico file. See set_overlay_icon 
+  /// - **Linux / macOS**: Badge count is app-wide and not specific to this window. Only supported desktop environments with `libunity` (e.g. GNOME).
+  /// - **iOS / Android:** Unsupported.
+  #[inline]
+  pub fn set_badge_count(&self, _count: Option<i64>, _desktop_filename: Option<String>) {
+    #[cfg(target_os = "macos")]
+    self.window.set_badge_label(_count.map(|c| c.to_string()));
+
+    #[cfg(any(
+      target_os = "linux",
+      target_os = "dragonfly",
+      target_os = "freebsd",
+      target_os = "netbsd",
+      target_os = "openbsd",
+    ))]
+    self.window.set_badge_count(_count, _desktop_filename);
+  }
+
   /// Requests user attention to the window, this has no effect if the application
   /// is already focused. How requesting for user attention manifests is platform dependent,
   /// see `UserAttentionType` for details.