status line: Custom widget for mouse input handling

cosmic-applet-status-line/Cargo.toml

@@ -4,6 +4,7 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+delegate = "0.9"
 libcosmic = { git = "https://github.com/pop-os/libcosmic/", branch = "master", default-features = false, features = ["tokio", "wayland", "applet"] }
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"

cosmic-applet-status-line/src/bar_widget.rs

@@ -0,0 +1,142 @@
+use cosmic::{
+    iced::{Length, Point, Rectangle},
+    iced_native::{
+        clipboard::Clipboard,
+        event::{self, Event},
+        layout::{Layout, Limits, Node},
+        mouse,
+        renderer::Style,
+        touch,
+        widget::{self, operation::Operation, Tree, Widget},
+        Shell,
+    },
+};
+
+use crate::protocol::ClickEvent;
+
+const BTN_LEFT: u32 = 0x110;
+const BTN_RIGHT: u32 = 0x111;
+const BTN_MIDDLE: u32 = 0x112;
+
+/// Wraps a `Row` widget, handling mouse input
+pub struct BarWidget<'a, Msg> {
+    pub row: widget::Row<'a, Msg, cosmic::Renderer>,
+    pub name_instance: Vec<(Option<&'a str>, Option<&'a str>)>,
+    pub on_press: fn(ClickEvent) -> Msg,
+}
+
+impl<'a, Msg> Widget<Msg, cosmic::Renderer> for BarWidget<'a, Msg> {
+    delegate::delegate! {
+        to self.row {
+            fn children(&self) -> Vec<Tree>;
+            fn diff(&self, tree: &mut Tree);
+            fn layout(&self, renderer: &cosmic::Renderer, limits: &Limits) -> Node;
+            fn operate(
+                &self,
+                tree: &mut Tree,
+                layout: Layout<'_>,
+                operation: &mut dyn Operation<Msg>,
+            );
+            fn draw(
+                &self,
+                state: &Tree,
+                renderer: &mut cosmic::Renderer,
+                theme: &cosmic::Theme,
+                style: &Style,
+                layout: Layout,
+                cursor_position: Point,
+                viewport: &Rectangle,
+            );
+        }
+    }
+
+    fn width(&self) -> Length {
+        Widget::width(&self.row)
+    }
+
+    fn height(&self) -> Length {
+        Widget::height(&self.row)
+    }
+
+    fn on_event(
+        &mut self,
+        tree: &mut Tree,
+        event: Event,
+        layout: Layout<'_>,
+        cursor_position: Point,
+        renderer: &cosmic::Renderer,
+        clipboard: &mut dyn Clipboard,
+        shell: &mut Shell<'_, Msg>,
+    ) -> event::Status {
+        if self.update(&event, layout, cursor_position, shell) == event::Status::Captured {
+            return event::Status::Captured;
+        }
+        self.row.on_event(
+            tree,
+            event,
+            layout,
+            cursor_position,
+            renderer,
+            clipboard,
+            shell,
+        )
+    }
+}
+
+impl<'a, Msg> From<BarWidget<'a, Msg>> for cosmic::Element<'a, Msg>
+where
+    Msg: 'a,
+{
+    fn from(widget: BarWidget<'a, Msg>) -> cosmic::Element<'a, Msg> {
+        cosmic::Element::new(widget)
+    }
+}
+
+impl<'a, Msg> BarWidget<'a, Msg> {
+    fn update(
+        &mut self,
+        event: &Event,
+        layout: Layout<'_>,
+        cursor_position: Point,
+        shell: &mut Shell<'_, Msg>,
+    ) -> event::Status {
+        let (button, event_code) = match event {
+            Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left)) => (1, BTN_LEFT),
+            Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Middle)) => (2, BTN_MIDDLE),
+            Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Right)) => (3, BTN_RIGHT),
+            Event::Touch(touch::Event::FingerPressed { .. }) => (1, BTN_LEFT),
+            _ => {
+                return event::Status::Ignored;
+            }
+        };
+
+        let Some((n, bounds)) = layout.children().map(|x| x.bounds()).enumerate().find(|(_, bounds)| bounds.contains(cursor_position)) else {
+            return event::Status::Ignored;
+        };
+
+        let (name, instance) = self.name_instance.get(n).cloned().unwrap_or((None, None));
+
+        // TODO coordinate space? int conversion?
+        let x = cursor_position.x as u32;
+        let y = cursor_position.y as u32;
+        let relative_x = (cursor_position.x - bounds.x) as u32;
+        let relative_y = (cursor_position.y - bounds.y) as u32;
+        let width = bounds.width as u32;
+        let height = bounds.height as u32;
+
+        shell.publish((self.on_press)(ClickEvent {
+            name: name.map(str::to_owned),
+            instance: instance.map(str::to_owned),
+            x,
+            y,
+            button,
+            event: event_code,
+            relative_x,
+            relative_y,
+            width,
+            height,
+        }));
+
+        event::Status::Captured
+    }
+}

cosmic-applet-status-line/src/main.rs

@@ -8,11 +8,14 @@ use cosmic::{
     iced_style::application,
 };
 
+mod bar_widget;
+use bar_widget::BarWidget;
 mod protocol;
 
 #[derive(Debug)]
 enum Msg {
     Protocol(protocol::StatusLine),
+    ClickEvent(protocol::ClickEvent),
     CloseRequest,
 }
 
@@ -56,13 +59,35 @@ impl iced::Application for App {
                 println!("{:?}", status_line);
                 self.status_line = status_line;
             }
+            Msg::ClickEvent(click_event) => {
+                println!("{:?}", click_event);
+                if self.status_line.click_events {
+                    // TODO: pass click event to backend
+                }
+            }
             Msg::CloseRequest => {}
         }
         iced::Command::none()
     }
 
     fn view(&self, _id: window::Id) -> cosmic::Element<Msg> {
-        iced::widget::row(self.status_line.blocks.iter().map(block_view).collect()).into()
+        let (block_views, name_instance): (Vec<_>, Vec<_>) = self
+            .status_line
+            .blocks
+            .iter()
+            .map(|block| {
+                (
+                    block_view(block),
+                    (block.name.as_deref(), block.instance.as_deref()),
+                )
+            })
+            .unzip();
+        BarWidget {
+            row: iced::widget::row(block_views),
+            name_instance,
+            on_press: Msg::ClickEvent,
+        }
+        .into()
     }
 }
 

cosmic-applet-status-line/src/protocol/mod.rs

@@ -10,8 +10,8 @@ use std::{
 use tokio::sync::mpsc;
 
 mod serialization;
-pub use serialization::Block;
 use serialization::Header;
+pub use serialization::{Block, ClickEvent};
 
 #[derive(Debug, Default)]
 pub struct StatusLine {

cosmic-applet-status-line/src/protocol/serialization.rs

@@ -128,15 +128,15 @@ pub struct Block {
 }
 
 #[derive(Clone, Debug, serde::Serialize)]
-struct ClickEvent {
-    name: Option<String>,
-    instance: Option<String>,
-    x: u32,
-    y: u32,
-    button: u32,
-    event: u32,
-    relative_x: u32,
-    relative_y: u32,
-    width: u32,
-    height: u32,
+pub struct ClickEvent {
+    pub name: Option<String>,
+    pub instance: Option<String>,
+    pub x: u32,
+    pub y: u32,
+    pub button: u32,
+    pub event: u32,
+    pub relative_x: u32,
+    pub relative_y: u32,
+    pub width: u32,
+    pub height: u32,
 }