wip: applet workspaces

applets/cosmic-applet-workspaces/Cargo.toml

@@ -0,0 +1,23 @@
+[package]
+name = "cosmic-applet-workspaces"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+[dependencies]
+cosmic-panel-config = { git="https://github.com/pop-os/cosmic-panel/", features = ["gtk4"] }
+cascade = "1.0.0"
+gtk4 = { version = "0.4.5", features = ["v4_4"] }
+once_cell = "1.9.0"
+pretty_env_logger = "0.4"
+anyhow = "1.0.50"
+i18n-embed = { version = "0.13.4", features = ["fluent-system", "desktop-requester"] }
+i18n-embed-fl = "0.6.4"
+rust-embed = "6.3.0"
+tokio = { version = "1.16.1", features = ["sync"] }
+
+
+[build-dependencies]
+gio = "0.15.10"

applets/cosmic-applet-workspaces/build.rs

@@ -0,0 +1,7 @@
+fn main() {
+    gio::compile_resources(
+        "data/resources",
+        "data/resources/resources.gresource.xml",
+        "compiled.gresource",
+    );
+}

applets/cosmic-applet-workspaces/data/com.system76.CosmicAppletWorkspaces.desktop

@@ -0,0 +1,12 @@
+[Desktop Entry]
+Name=Cosmic Applet Power
+Comment=Write a GTK + Rust application
+Type=Application
+Exec=cosmic-applet-power
+Terminal=false
+Categories=GNOME;GTK;
+Keywords=Gnome;GTK;
+# Translators: Do NOT translate or transliterate this text (this is an icon file name)!
+Icon=com.system76.CosmicAppletPower.svg
+StartupNotify=true
+NoDisplay=true

applets/cosmic-applet-workspaces/data/icons/com.system76.CosmicAppletWorkspaces.svg

@@ -0,0 +1,60 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="128px" height="128px" viewBox="0 0 128 128" version="1.1">
+<defs>
+<filter id="alpha" filterUnits="objectBoundingBox" x="0%" y="0%" width="100%" height="100%">
+  <feColorMatrix type="matrix" in="SourceGraphic" values="0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0"/>
+</filter>
+<mask id="mask0">
+  <g filter="url(#alpha)">
+<rect x="0" y="0" width="128" height="128" style="fill:rgb(0%,0%,0%);fill-opacity:0.1;stroke:none;"/>
+  </g>
+</mask>
+<clipPath id="clip1">
+  <rect x="0" y="0" width="192" height="152"/>
+</clipPath>
+<g id="surface10632" clip-path="url(#clip1)">
+<path style="fill:none;stroke-width:0.99;stroke-linecap:butt;stroke-linejoin:miter;stroke:rgb(0%,0%,0%);stroke-opacity:1;stroke-dasharray:0.99,0.99;stroke-miterlimit:4;" d="M 123.503906 236 C 123.503906 268.863281 96.863281 295.503906 64 295.503906 C 31.136719 295.503906 4.496094 268.863281 4.496094 236 C 4.496094 203.136719 31.136719 176.496094 64 176.496094 C 96.863281 176.496094 123.503906 203.136719 123.503906 236 Z M 123.503906 236 " transform="matrix(1,0,0,1,8,-156)"/>
+</g>
+<mask id="mask1">
+  <g filter="url(#alpha)">
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+</mask>
+<clipPath id="clip2">
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+</clipPath>
+<g id="surface10635" clip-path="url(#clip2)">
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+</g>
+<mask id="mask2">
+  <g filter="url(#alpha)">
+<rect x="0" y="0" width="128" height="128" style="fill:rgb(0%,0%,0%);fill-opacity:0.1;stroke:none;"/>
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+</mask>
+<clipPath id="clip3">
+  <rect x="0" y="0" width="192" height="152"/>
+</clipPath>
+<g id="surface10638" clip-path="url(#clip3)">
+<path style="fill:none;stroke-width:0.99;stroke-linecap:butt;stroke-linejoin:miter;stroke:rgb(0%,0%,0%);stroke-opacity:1;stroke-dasharray:0.99,0.99;stroke-miterlimit:4;" d="M 20.417969 184.496094 L 107.582031 184.496094 C 111.957031 184.496094 115.503906 188.042969 115.503906 192.417969 L 115.503906 279.582031 C 115.503906 283.957031 111.957031 287.503906 107.582031 287.503906 L 20.417969 287.503906 C 16.042969 287.503906 12.496094 283.957031 12.496094 279.582031 L 12.496094 192.417969 C 12.496094 188.042969 16.042969 184.496094 20.417969 184.496094 Z M 20.417969 184.496094 " transform="matrix(1,0,0,1,8,-156)"/>
+</g>
+<mask id="mask3">
+  <g filter="url(#alpha)">
+<rect x="0" y="0" width="128" height="128" style="fill:rgb(0%,0%,0%);fill-opacity:0.1;stroke:none;"/>
+  </g>
+</mask>
+<clipPath id="clip4">
+  <rect x="0" y="0" width="192" height="152"/>
+</clipPath>
+<g id="surface10641" clip-path="url(#clip4)">
+<path style="fill:none;stroke-width:0.99;stroke-linecap:butt;stroke-linejoin:miter;stroke:rgb(0%,0%,0%);stroke-opacity:1;stroke-dasharray:0.99,0.99;stroke-miterlimit:4;" d="M 16.425781 200.496094 L 111.574219 200.496094 C 115.953125 200.496094 119.503906 204.390625 119.503906 209.195312 L 119.503906 278.804688 C 119.503906 283.609375 115.953125 287.503906 111.574219 287.503906 L 16.425781 287.503906 C 12.046875 287.503906 8.496094 283.609375 8.496094 278.804688 L 8.496094 209.195312 C 8.496094 204.390625 12.046875 200.496094 16.425781 200.496094 Z M 16.425781 200.496094 " transform="matrix(1,0,0,1,8,-156)"/>
+</g>
+</defs>
+<g id="surface10578">
+<rect x="0" y="0" width="128" height="128" style="fill:rgb(94.117647%,94.117647%,94.117647%);fill-opacity:1;stroke:none;"/>
+<use xlink:href="#surface10632" transform="matrix(1,0,0,1,-8,-16)" mask="url(#mask0)"/>
+<use xlink:href="#surface10635" transform="matrix(1,0,0,1,-8,-16)" mask="url(#mask1)"/>
+<use xlink:href="#surface10638" transform="matrix(1,0,0,1,-8,-16)" mask="url(#mask2)"/>
+<use xlink:href="#surface10641" transform="matrix(1,0,0,1,-8,-16)" mask="url(#mask3)"/>
+<path style="fill:none;stroke-width:2;stroke-linecap:butt;stroke-linejoin:miter;stroke:rgb(38.431373%,62.7451%,91.764706%);stroke-opacity:1;stroke-miterlimit:4;" d="M 0 289 L 128 289 " transform="matrix(1,0,0,1,0,-172)"/>
+</g>
+</svg>

applets/cosmic-applet-workspaces/data/resources/resources.gresource.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<gresources>
+  <gresource prefix="/com/System76/CosmicDockAppList/">
+    <!-- see https://gtk-rs.org/gtk4-rs/git/docs/gtk4/struct.Application.html#automatic-resources -->
+  </gresource>
+</gresources>

applets/cosmic-applet-workspaces/i18n.toml

@@ -0,0 +1,4 @@
+fallback_language = "en"
+
+[fluent]
+assets_dir = "i18n"

applets/cosmic-applet-workspaces/i18n/en/cosmic_applet_workspaces.ftl

@@ -0,0 +1 @@
+cosmic-app-list = Cosmic Dock App List

applets/cosmic-applet-workspaces/src/localize.rs

@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: MPL-2.0-only
+
+use i18n_embed::{
+    fluent::{fluent_language_loader, FluentLanguageLoader},
+    DefaultLocalizer, LanguageLoader, Localizer,
+};
+use once_cell::sync::Lazy;
+use rust_embed::RustEmbed;
+
+#[derive(RustEmbed)]
+#[folder = "i18n/"]
+struct Localizations;
+
+pub static LANGUAGE_LOADER: Lazy<FluentLanguageLoader> = Lazy::new(|| {
+    let loader: FluentLanguageLoader = fluent_language_loader!();
+
+    loader
+        .load_fallback_language(&Localizations)
+        .expect("Error while loading fallback language");
+
+    loader
+});
+
+#[macro_export]
+macro_rules! fl {
+    ($message_id:literal) => {{
+        i18n_embed_fl::fl!($crate::localize::LANGUAGE_LOADER, $message_id)
+    }};
+
+    ($message_id:literal, $($args:expr),*) => {{
+        i18n_embed_fl::fl!($crate::localize::LANGUAGE_LOADER, $message_id, $($args), *)
+    }};
+}
+
+// Get the `Localizer` to be used for localizing this library.
+pub fn localizer() -> Box<dyn Localizer> {
+    Box::from(DefaultLocalizer::new(&*LANGUAGE_LOADER, &Localizations))
+}

applets/cosmic-applet-workspaces/src/main.rs

@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: MPL-2.0-only
+
+use gtk4::{gdk::Display, gio::{self, ApplicationFlags}, glib, prelude::*, CssProvider, StyleContext};
+use once_cell::sync::OnceCell;
+use window::CosmicWorkspacesWindow;
+use std::sync::{Arc, Mutex};
+use tokio::sync::mpsc;
+use utils::{Event, BoxedWorkspaceList};
+
+mod window;
+mod workspace_button;
+mod workspace_list;
+mod wayland;
+mod localize;
+mod utils;
+mod workspace_object;
+
+const ID: &str = "com.system76.CosmicAppletWorkspaces";
+static TX: OnceCell<mpsc::Sender<Event>> = OnceCell::new();
+
+pub fn localize() {
+    let localizer = crate::localize::localizer();
+    let requested_languages = i18n_embed::DesktopLanguageRequester::requested_languages();
+
+    if let Err(error) = localizer.select(&requested_languages) {
+        eprintln!("Error while loading language for App List {}", error);
+    }
+}
+
+fn load_css() {
+    let provider = CssProvider::new();
+    provider.load_from_resource("/com.system76.CosmicAppletWorkspaces/style.css");
+
+    StyleContext::add_provider_for_display(
+        &Display::default().unwrap(),
+        &provider,
+        gtk4::STYLE_PROVIDER_PRIORITY_APPLICATION,
+    );
+}
+
+fn main() {
+    // Initialize logger
+    pretty_env_logger::init();
+    glib::set_application_name(ID);
+
+    localize();
+    gio::resources_register_include!("compiled.gresource").unwrap();
+
+    let app = gtk4::Application::new(Some(ID), ApplicationFlags::default());
+
+    app.connect_activate(|app| {
+        load_css();
+        let (tx, mut rx) = mpsc::channel(100);
+
+        let window = CosmicWorkspacesWindow::new(app, tx.clone());
+
+        let workspace_list = Arc::new(Mutex::new(Vec::<BoxedWorkspaceList>::new()));
+
+        TX.set(tx.clone()).unwrap();
+
+        let _ = glib::MainContext::default().spawn_local(async move {
+            while let Some(event) = rx.recv().await {
+                match event {
+                    Event::Activate(_) => {
+                        // TODO activate the selected workspace
+                    }
+                    Event::WorkspaceList => {
+                        // TODO update the model with the new workspace list
+                    }
+                }
+            }
+        });
+        window.show();
+    });
+    app.run();
+}

applets/cosmic-applet-workspaces/src/utils.rs

@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: MPL-2.0-only
+
+use std::path::PathBuf;
+
+use gtk4::glib;
+use std::future::Future;
+
+#[derive(Debug)]
+pub enum Event {
+    WorkspaceList,
+    Activate(u32),
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct Workspace {
+    pub(crate) id: u32,
+    pub(crate) active: bool,
+}
+
+#[derive(Clone, Debug, Default, glib::Boxed)]
+#[boxed_type(name = "BoxedWorkspace")]
+pub struct BoxedWorkspace(pub Option<Workspace>);
+
+#[derive(Clone, Debug, Default, glib::Boxed)]
+#[boxed_type(name = "BoxedWorkspaceList")]
+pub struct BoxedWorkspaceList(pub Vec<Workspace>);
+
+pub fn data_path() -> PathBuf {
+    let mut path = glib::user_data_dir();
+    path.push(crate::ID);
+    std::fs::create_dir_all(&path).expect("Could not create directory.");
+    path.push("data.json");
+    path
+}
+
+pub fn thread_context() -> glib::MainContext {
+    glib::MainContext::thread_default().unwrap_or_else(|| {
+        let ctx = glib::MainContext::new();
+        ctx
+    })
+}
+
+pub fn block_on<F>(future: F) -> F::Output
+where
+    F: Future,
+{
+    let ctx = thread_context();
+    ctx.with_thread_default(|| ctx.block_on(future)).unwrap()
+}

applets/cosmic-applet-workspaces/src/window/imp.rs

@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: MPL-2.0-only
+
+use gtk4::{glib, subclass::prelude::*};
+use once_cell::sync::OnceCell;
+use crate::{workspace_list::WorkspaceList};
+
+// Object holding the state
+#[derive(Default)]
+pub struct CosmicWorkspacesWindow {
+    pub(super) inner: OnceCell<WorkspaceList>,
+}
+
+// The central trait for subclassing a GObject
+#[glib::object_subclass]
+impl ObjectSubclass for CosmicWorkspacesWindow {
+    // `NAME` needs to match `class` attribute of template
+    const NAME: &'static str = "CosmicWorkspacesWindow";
+    type Type = super::CosmicWorkspacesWindow;
+    type ParentType = gtk4::ApplicationWindow;
+}
+
+// Trait shared by all GObjects
+impl ObjectImpl for CosmicWorkspacesWindow {}
+
+// Trait shared by all widgets
+impl WidgetImpl for CosmicWorkspacesWindow {}
+
+// Trait shared by all windows
+impl WindowImpl for CosmicWorkspacesWindow {}
+
+// Trait shared by all application
+impl ApplicationWindowImpl for CosmicWorkspacesWindow {}

applets/cosmic-applet-workspaces/src/window/mod.rs

@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: MPL-2.0-only
+
+use crate::{fl, utils::Event, workspace_list::WorkspaceList};
+use cascade::cascade;
+use cosmic_panel_config::config::CosmicPanelConfig;
+use gtk4::{
+    gio,
+    glib::{self, Object},
+    prelude::*,
+    subclass::prelude::*,
+};
+use tokio::sync::mpsc;
+
+mod imp;
+
+glib::wrapper! {
+    pub struct CosmicWorkspacesWindow(ObjectSubclass<imp::CosmicWorkspacesWindow>)
+        @extends gtk4::ApplicationWindow, gtk4::Window, gtk4::Widget,
+        @implements gio::ActionGroup, gio::ActionMap, gtk4::Accessible, gtk4::Buildable,
+                    gtk4::ConstraintTarget, gtk4::Native, gtk4::Root, gtk4::ShortcutManager;
+}
+
+impl CosmicWorkspacesWindow {
+    pub fn new(app: &gtk4::Application, tx: mpsc::Sender<Event>) -> Self {
+        let self_: Self = Object::new(&[("application", app)])
+            .expect("Failed to create `CosmicWorkspacesWindow`.");
+        let imp = imp::CosmicWorkspacesWindow::from_instance(&self_);
+
+        cascade! {
+            &self_;
+            ..set_width_request(1);
+            ..set_height_request(1);
+            ..set_decorated(false);
+            ..set_resizable(false);
+            ..set_title(Some(&fl!("cosmic-app-list")));
+            ..add_css_class("transparent");
+        };
+        let config = CosmicPanelConfig::load_from_env().unwrap_or_default();
+
+        let app_list = WorkspaceList::new(tx, config);
+        self_.set_child(Some(&app_list));
+        imp.inner.set(app_list).unwrap();
+
+        self_
+    }
+}

applets/cosmic-applet-workspaces/src/workspace_button/imp.rs

@@ -0,0 +1,29 @@
+use std::{rc::Rc, cell::RefCell};
+use gtk4::{Label, ToggleButton, glib, subclass::prelude::*};
+use tokio::sync::mpsc;
+use once_cell::sync::OnceCell;
+use crate::Event;
+
+// Object holding the state
+#[derive(Default)]
+pub struct WorkspaceButton {
+    pub tx: Rc<OnceCell<mpsc::Sender<Event>>>,
+    pub button: Rc<RefCell<ToggleButton>>,
+}
+
+// The central trait for subclassing a GObject
+#[glib::object_subclass]
+impl ObjectSubclass for WorkspaceButton {
+    const NAME: &'static str = "WorkspaceButton";
+    type Type = super::WorkspaceButton;
+    type ParentType = gtk4::Box;
+}
+
+// Trait shared by all GObjects
+impl ObjectImpl for WorkspaceButton {}
+
+// Trait shared by all widgets
+impl WidgetImpl for WorkspaceButton {}
+
+// Trait shared by all buttons
+impl BoxImpl for WorkspaceButton {}

applets/cosmic-applet-workspaces/src/workspace_button/mod.rs

@@ -0,0 +1,43 @@
+mod imp;
+
+use glib::Object;
+use gtk4::{glib, prelude::*, subclass::prelude::*, ToggleButton};
+use tokio::sync::mpsc;
+use crate::{Event, workspace_object::WorkspaceObject};
+
+glib::wrapper! {
+    pub struct WorkspaceButton(ObjectSubclass<imp::WorkspaceButton>)
+        @extends gtk4::Box, gtk4::Widget,
+        @implements gtk4::Accessible, gtk4::Actionable, gtk4::Buildable, gtk4::ConstraintTarget, gtk4::Orientable;
+}
+
+impl WorkspaceButton {
+    pub fn new(tx: mpsc::Sender<Event>) -> Self {
+        let self_ = Object::new(&[]).expect("Failed to create `WorkspaceButton`.");
+        let imp = imp::WorkspaceButton::from_instance(&self_);
+        imp.tx.set(tx).unwrap();
+
+        let tb = ToggleButton::with_label("");
+        self_.append(&tb);
+
+        imp.button.replace(tb);
+        
+        self_
+    }
+
+    pub fn set_workspace_object(&self, obj: &WorkspaceObject) {
+        let imp = imp::WorkspaceButton::from_instance(&self);
+        let old_button = imp.button.take();
+        self.remove(&old_button);
+
+        let id = obj.id();
+        let new_button = ToggleButton::with_label(&format!("{}", id));
+        new_button.set_active(obj.active());
+        self.append(&new_button);
+        new_button.connect_clicked(glib::clone!(@weak imp.tx as tx => move |_| {
+            let _ = tx.get().unwrap().send(Event::Activate(id));
+        }));
+
+        imp.button.replace(new_button);
+    }
+}

applets/cosmic-applet-workspaces/src/workspace_list/imp.rs

@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: MPL-2.0-only
+
+use cosmic_panel_config::config::{Anchor, CosmicPanelConfig};
+use glib::SignalHandlerId;
+use gtk4::subclass::prelude::*;
+use gtk4::{gio, glib};
+use gtk4::{Box, DragSource, DropTarget, GestureClick, ListView};
+use once_cell::sync::OnceCell;
+use std::cell::{Cell, RefCell};
+use std::rc::Rc;
+use tokio::sync::mpsc;
+
+use crate::utils::Event;
+
+#[derive(Debug, Default)]
+pub struct WorkspaceList {
+    pub list_view: OnceCell<ListView>,
+    pub model: OnceCell<gio::ListStore>,
+    pub click_controller: OnceCell<GestureClick>,
+    pub tx: OnceCell<mpsc::Sender<Event>>,
+    pub config: OnceCell<CosmicPanelConfig>
+}
+
+#[glib::object_subclass]
+impl ObjectSubclass for WorkspaceList {
+    const NAME: &'static str = "WorkspaceList";
+    type Type = super::WorkspaceList;
+    type ParentType = Box;
+}
+
+impl ObjectImpl for WorkspaceList {}
+
+impl WidgetImpl for WorkspaceList {}
+
+impl BoxImpl for WorkspaceList {}

applets/cosmic-applet-workspaces/src/workspace_list/mod.rs

@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: MPL-2.0-only
+
+use crate::utils::{Event, BoxedWorkspace};
+use crate::workspace_button::WorkspaceButton;
+use crate::workspace_object::WorkspaceObject;
+use cascade::cascade;
+use cosmic_panel_config::config::{CosmicPanelConfig};
+use gtk4::{glib, gio, prelude::*, subclass::prelude::*};
+use gtk4::ListView;
+use gtk4::Orientation;
+use gtk4::SignalListItemFactory;
+use tokio::sync::mpsc::Sender;
+
+mod imp;
+
+glib::wrapper! {
+    pub struct WorkspaceList(ObjectSubclass<imp::WorkspaceList>)
+        @extends gtk4::Widget, gtk4::Box,
+        @implements gtk4::Accessible, gtk4::Buildable, gtk4::ConstraintTarget, gtk4::Orientable;
+}
+
+impl WorkspaceList {
+    pub fn new(tx: Sender<Event>, config: CosmicPanelConfig) -> Self {
+        let self_: WorkspaceList = glib::Object::new(&[]).expect("Failed to create WorkspaceList");
+        let imp = imp::WorkspaceList::from_instance(&self_);
+        imp.tx.set(tx).unwrap();
+        imp.config.set(config).unwrap();
+        self_.layout();
+        //dnd behavior is different for each type, as well as the data in the model
+        self_.setup_model();
+        self_.setup_factory();
+        self_
+    }
+
+    pub fn model(&self) -> &gio::ListStore {
+        // Get state
+        let imp = imp::WorkspaceList::from_instance(self);
+        imp.model.get().expect("Could not get model")
+    }
+
+    fn layout(&self) {
+        let imp = imp::WorkspaceList::from_instance(self);
+        let list_view = cascade! {
+            ListView::default();
+            ..set_orientation(Orientation::Horizontal);
+            ..add_css_class("transparent");
+        };
+        self.append(&list_view);
+        imp.list_view.set(list_view).unwrap();
+    }
+
+    fn setup_model(&self) {
+        let imp = imp::WorkspaceList::from_instance(self);
+        let model = gio::ListStore::new(BoxedWorkspace::static_type());
+
+        let selection_model = gtk4::NoSelection::new(Some(&model));
+
+        // Wrap model with selection and pass it to the list view
+        let list_view = imp.list_view.get().unwrap();
+        list_view.set_model(Some(&selection_model));
+        imp.model.set(model).expect("Could not set model");
+    }
+
+    fn setup_factory(&self) {
+        let imp = imp::WorkspaceList::from_instance(self);
+        let factory = SignalListItemFactory::new();
+        let model = imp.model.get().expect("Failed to get saved app model.");
+        let tx = imp.tx.get().unwrap().clone();
+        let icon_size = imp.config.get().unwrap().get_applet_icon_size();
+        factory.connect_setup(
+            glib::clone!(@weak model => move |_, list_item| {
+                let workspace_button = WorkspaceButton::new(tx.clone());
+                list_item.set_child(Some(&workspace_button));
+            }),
+        );
+        factory.connect_bind(|_, list_item| {
+                let workspace_object = list_item
+                    .item()
+                    .expect("The item has to exist.")
+                    .downcast::<WorkspaceObject>()
+                    .expect("The item has to be a `DockObject`");
+                let workspace_button = list_item
+                    .child()
+                    .expect("The list item child needs to exist.")
+                    .downcast::<WorkspaceButton>()
+                    .expect("The list item type needs to be `DockItem`");
+                workspace_button.set_workspace_object(&workspace_object);
+            },
+        );
+        // Set the factory of the list view
+        imp.list_view.get().unwrap().set_factory(Some(&factory));
+    }
+}

applets/cosmic-applet-workspaces/src/workspace_object/imp.rs

@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: MPL-2.0-only
+
+use std::cell::Cell;
+use std::cell::RefCell;
+
+use glib::{ParamFlags, ParamSpec, Value};
+use gtk4::gdk::glib::ParamSpecBoolean;
+use gtk4::glib;
+use gtk4::glib::ParamSpecUInt;
+use gtk4::prelude::*;
+use gtk4::subclass::prelude::*;
+use once_cell::sync::Lazy;
+
+// Object holding the state
+#[derive(Default)]
+pub struct WorkspaceObject {
+    pub(crate) id: Cell<u32>,
+    pub(crate) active: Cell<bool>,
+}
+
+// The central trait for subclassing a GObject
+#[glib::object_subclass]
+impl ObjectSubclass for WorkspaceObject {
+    const NAME: &'static str = "WorkspaceObject";
+    type Type = super::WorkspaceObject;
+    type ParentType = glib::Object;
+}
+
+// Trait shared by all GObjects
+impl ObjectImpl for WorkspaceObject {
+    fn properties() -> &'static [ParamSpec] {
+        static PROPERTIES: Lazy<Vec<ParamSpec>> = Lazy::new(|| {
+            vec![
+                ParamSpecUInt::new(
+                    // Name
+                    "id",
+                    // Nickname
+                    "id",
+                    // Short description
+                    "id",
+                    // Minimum value
+                    u32::MIN,
+                    // Maximum value
+                    u32::MAX,
+                    // Default value
+                    0,
+                    // The property can be read and written to
+                    ParamFlags::READWRITE,
+                ),
+                ParamSpecBoolean::new(
+                    "active",
+                    "active",
+                    "Indicates whether workspace is active",
+                    false,
+                    ParamFlags::READWRITE,
+                ),
+                
+            ]
+        });
+        PROPERTIES.as_ref()
+    }
+
+    fn set_property(&self, _obj: &Self::Type, _id: usize, value: &Value, pspec: &ParamSpec) {
+        match pspec.name() {
+            "active" => {
+                self.active
+                    .replace(value.get().expect("Value needs to be a boolean"));
+            }
+            "id" => {
+                self.id
+                    .replace(value.get().expect("Value needs to be a boolean"));
+            }
+            _ => unimplemented!(),
+        }
+    }
+
+    fn property(&self, _obj: &Self::Type, _id: usize, pspec: &ParamSpec) -> Value {
+        match pspec.name() {
+            "id" => self.id.get().to_value(),
+            "active" => self.active.get().to_value(),
+            _ => unimplemented!(),
+        }
+    }
+}

applets/cosmic-applet-workspaces/src/workspace_object/mod.rs

@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: MPL-2.0-only
+
+use gtk4::{glib, subclass::prelude::*};
+
+mod imp;
+
+glib::wrapper! {
+    pub struct WorkspaceObject(ObjectSubclass<imp::WorkspaceObject>);
+}
+
+impl WorkspaceObject {
+    pub fn new() -> Self {
+        glib::Object::new(&[]).unwrap()
+    }
+
+    pub fn from_id_active(id: u32, active: bool) -> Self {
+        glib::Object::new(&[("id", &id), ("active", &active)]).unwrap()
+    }
+
+    pub fn id(&self) -> u32 {
+        imp::WorkspaceObject::from_instance(&self).id.get()
+    } 
+
+    pub fn active(&self) -> bool {
+        imp::WorkspaceObject::from_instance(&self).active.get()
+    } 
+}
+
+#[derive(Clone, Debug, Default, glib::Boxed)]
+#[boxed_type(name = "BoxedWorkspaceObject")]
+pub struct BoxedWorkspaceObject(pub Option<WorkspaceObject>);