dock: Add version to DockArea to allow us check the persisted state is need to update.

crates/app/src/story_workspace.rs

@@ -21,6 +21,11 @@ use workspace::TitleBar;
 
 use crate::app_state::AppState;
 
+const MAIN_DOCK_AREA: DockAreaTab = DockAreaTab {
+    id: "main-dock",
+    version: 3,
+};
+
 #[derive(Clone, PartialEq, Eq, Deserialize)]
 struct SelectLocale(SharedString);
 
@@ -43,14 +48,20 @@ pub struct StoryWorkspace {
     _save_layout_task: Option<Task<()>>,
 }
 
+struct DockAreaTab {
+    id: &'static str,
+    version: usize,
+}
+
 impl StoryWorkspace {
     pub fn new(_app_state: Arc<AppState>, cx: &mut ViewContext<Self>) -> Self {
         cx.observe_window_appearance(|_, cx| {
             Theme::sync_system_appearance(cx);
         })
         .detach();
 
-        let dock_area = cx.new_view(|cx| DockArea::new("main-dock", cx));
+        let dock_area =
+            cx.new_view(|cx| DockArea::new(MAIN_DOCK_AREA.id, Some(MAIN_DOCK_AREA.version), cx));
         let weak_dock_area = dock_area.downgrade();
 
         match Self::load_layout(dock_area.clone(), cx) {
@@ -59,25 +70,7 @@ impl StoryWorkspace {
             }
             Err(err) => {
                 eprintln!("load layout error: {:?}", err);
-                let dock_item = Self::init_default_layout(&weak_dock_area, cx);
-
-                let left_panels: Vec<Arc<dyn PanelView>> =
-                    vec![Arc::new(StoryContainer::panel::<ListStory>(cx))];
-
-                let bottom_panels: Vec<Arc<dyn PanelView>> = vec![
-                    Arc::new(StoryContainer::panel::<TooltipStory>(cx)),
-                    Arc::new(StoryContainer::panel::<IconStory>(cx)),
-                ];
-
-                let right_panels: Vec<Arc<dyn PanelView>> =
-                    vec![Arc::new(StoryContainer::panel::<ImageStory>(cx))];
-
-                _ = dock_area.update(cx, |view, cx| {
-                    view.set_root(dock_item, cx);
-                    view.set_left_dock(left_panels, Some(px(350.)), cx);
-                    view.set_bottom_dock(bottom_panels, Some(px(200.)), cx);
-                    view.set_right_dock(right_panels, Some(px(320.)), cx);
-                });
+                Self::reset_default_layout(weak_dock_area, cx);
             }
         };
 
@@ -166,22 +159,63 @@ impl StoryWorkspace {
         let json = std::fs::read_to_string(fname)?;
         let state = serde_json::from_str::<DockAreaState>(&json)?;
 
+        // Check if the saved layout version is different from the current version
+        // Notify the user and ask if they want to reset the layout to default.
+        if state.version != Some(MAIN_DOCK_AREA.version) {
+            let answer = cx.prompt(PromptLevel::Info, "The default main layout has been updated.\nDo you want to reset the layout to default?", None,
+                &["Yes", "No"]);
+
+            let weak_dock_area = dock_area.downgrade();
+            cx.spawn(|mut cx| async move {
+                if answer.await == Ok(0) {
+                    _ = cx.update(|cx| {
+                        Self::reset_default_layout(weak_dock_area, cx);
+                    });
+                }
+            })
+            .detach();
+        }
+
         dock_area.update(cx, |dock_area, cx| {
             dock_area.load(state, cx).context("load layout")?;
 
             Ok::<(), anyhow::Error>(())
         })
     }
 
+    fn reset_default_layout(dock_area: WeakView<DockArea>, cx: &mut WindowContext) {
+        let dock_item = Self::init_default_layout(&dock_area, cx);
+        let left_panels: Vec<Arc<dyn PanelView>> =
+            vec![Arc::new(StoryContainer::panel::<ListStory>(cx))];
+
+        let bottom_panels: Vec<Arc<dyn PanelView>> = vec![
+            Arc::new(StoryContainer::panel::<TooltipStory>(cx)),
+            Arc::new(StoryContainer::panel::<IconStory>(cx)),
+        ];
+
+        let right_panels: Vec<Arc<dyn PanelView>> =
+            vec![Arc::new(StoryContainer::panel::<ImageStory>(cx))];
+
+        _ = dock_area.update(cx, |view, cx| {
+            view.set_version(MAIN_DOCK_AREA.version, cx);
+            view.set_root(dock_item, cx);
+            view.set_left_dock(left_panels, Some(px(350.)), cx);
+            view.set_bottom_dock(bottom_panels, Some(px(200.)), cx);
+            view.set_right_dock(right_panels, Some(px(320.)), cx);
+
+            Self::save_state(&view.dump(cx)).unwrap();
+        });
+    }
+
     fn init_default_layout(dock_area: &WeakView<DockArea>, cx: &mut WindowContext) -> DockItem {
         DockItem::split_with_sizes(
             Axis::Vertical,
             vec![DockItem::tabs(
                 vec![
                     Arc::new(StoryContainer::panel::<ButtonStory>(cx)),
                     Arc::new(StoryContainer::panel::<InputStory>(cx)),
-                    Arc::new(StoryContainer::panel::<TextStory>(cx)),
                     Arc::new(StoryContainer::panel::<DropdownStory>(cx)),
+                    Arc::new(StoryContainer::panel::<TextStory>(cx)),
                     Arc::new(StoryContainer::panel::<ModalStory>(cx)),
                     Arc::new(StoryContainer::panel::<PopupStory>(cx)),
                     Arc::new(StoryContainer::panel::<SwitchStory>(cx)),
@@ -191,10 +225,10 @@ impl StoryWorkspace {
                     Arc::new(StoryContainer::panel::<IconStory>(cx)),
                     Arc::new(StoryContainer::panel::<TooltipStory>(cx)),
                     Arc::new(StoryContainer::panel::<ProgressStory>(cx)),
+                    Arc::new(StoryContainer::panel::<WebViewStory>(cx)),
                     Arc::new(StoryContainer::panel::<CalendarStory>(cx)),
                     Arc::new(StoryContainer::panel::<ResizableStory>(cx)),
                     Arc::new(StoryContainer::panel::<ScrollableStory>(cx)),
-                    Arc::new(StoryContainer::panel::<WebViewStory>(cx)),
                 ],
                 None,
                 &dock_area,

crates/story/src/lib.rs

@@ -52,14 +52,16 @@ use ui::{
     v_flex, ContextModal,
 };
 
+const PANEL_NAME: &str = "StoryContainer";
+
 pub fn init(cx: &mut AppContext) {
     input_story::init(cx);
     dropdown_story::init(cx);
     popup_story::init(cx);
 
-    register_panel(cx, "StoryContainer", |_, info, cx| {
+    register_panel(cx, PANEL_NAME, |_, _, info, cx| {
         let story_state = match info {
-            DockItemInfo::Panel(value) => StoryState::from_value(value),
+            DockItemInfo::Panel(value) => StoryState::from_value(value.clone()),
             _ => {
                 unreachable!("Invalid DockItemInfo: {:?}", info)
             }
@@ -292,7 +294,7 @@ impl Panel for StoryContainer {
     }
 
     fn dump(&self, _cx: &AppContext) -> DockItemState {
-        let mut state = DockItemState::new(self.panel_name());
+        let mut state = DockItemState::new(self);
         let story_state = StoryState {
             story_klass: self.story_klass.clone().unwrap(),
         };

crates/ui/src/dock/invalid_panel.rs

@@ -28,7 +28,7 @@ impl Panel for InvalidPanel {
     }
 
     fn dump(&self, _cx: &AppContext) -> super::DockItemState {
-        let mut state = DockItemState::new(&self.name);
+        let mut state = DockItemState::new(self);
         state.info = self.info.clone();
         state
     }

crates/ui/src/dock/mod.rs

@@ -35,6 +35,8 @@ pub enum DockEvent {
 /// The main area of the dock.
 pub struct DockArea {
     id: SharedString,
+    /// The version is used to special the default layout, this is like the `panel_version` in `trait Panel`.
+    version: Option<usize>,
     pub(crate) bounds: Bounds<Pixels>,
 
     /// The center view of the dockarea.
@@ -181,7 +183,11 @@ impl DockItem {
 }
 
 impl DockArea {
-    pub fn new(id: impl Into<SharedString>, cx: &mut ViewContext<Self>) -> Self {
+    pub fn new(
+        id: impl Into<SharedString>,
+        version: Option<usize>,
+        cx: &mut ViewContext<Self>,
+    ) -> Self {
         let stack_panel = cx.new_view(|cx| StackPanel::new(Axis::Horizontal, cx));
         let dock_item = DockItem::Split {
             axis: Axis::Horizontal,
@@ -192,6 +198,7 @@ impl DockArea {
 
         Self {
             id: id.into(),
+            version,
             bounds: Bounds::default(),
             items: dock_item,
             zoom_view: None,
@@ -201,6 +208,12 @@ impl DockArea {
         }
     }
 
+    /// Set version of the dock area.
+    pub fn set_version(&mut self, version: usize, cx: &mut ViewContext<Self>) {
+        self.version = Some(version);
+        cx.notify();
+    }
+
     /// The the DockItem as the root of the dock area.
     ///
     /// This is used to render at the Center of the DockArea.
@@ -299,6 +312,7 @@ impl DockArea {
     ///
     /// See also [DockeArea::dump].
     pub fn load(&mut self, state: DockAreaState, cx: &mut ViewContext<Self>) -> Result<()> {
+        self.version = state.version;
         let weak_self = cx.view().downgrade();
 
         if let Some(left_dock) = state.left_dock {
@@ -348,6 +362,7 @@ impl DockArea {
             .map(|dock| DockState::new(dock.clone(), cx));
 
         DockAreaState {
+            version: self.version,
             center,
             left_dock,
             right_dock,

crates/ui/src/dock/panel.rs

@@ -60,33 +60,28 @@ pub trait Panel: EventEmitter<PanelEvent> + FocusableView {
 
     /// Dump the panel, used to serialize the panel.
     fn dump(&self, _cx: &AppContext) -> DockItemState {
-        DockItemState::new(self.panel_name())
+        DockItemState::new(self)
     }
 }
 
 pub trait PanelView: 'static + Send + Sync {
     fn panel_name(&self, _cx: &WindowContext) -> &'static str;
     fn title(&self, _cx: &WindowContext) -> AnyElement;
-
     fn title_style(&self, _cx: &WindowContext) -> Option<TitleStyle>;
-
     fn closeable(&self, cx: &WindowContext) -> bool;
     fn zoomable(&self, cx: &WindowContext) -> bool;
     fn collapsible(&self, cx: &WindowContext) -> bool;
-
     fn popup_menu(&self, menu: PopupMenu, cx: &WindowContext) -> PopupMenu;
-
     fn view(&self) -> AnyView;
-
     fn focus_handle(&self, cx: &AppContext) -> FocusHandle;
-
     fn dump(&self, cx: &AppContext) -> DockItemState;
 }
 
 impl<T: Panel> PanelView for View<T> {
     fn panel_name(&self, cx: &WindowContext) -> &'static str {
         self.read(cx).panel_name()
     }
+
     fn title(&self, cx: &WindowContext) -> AnyElement {
         self.read(cx).title(cx)
     }
@@ -145,7 +140,14 @@ impl PartialEq for dyn PanelView {
 pub struct PanelRegistry {
     pub(super) items: HashMap<
         String,
-        Arc<dyn Fn(WeakView<DockArea>, DockItemInfo, &mut WindowContext) -> Box<dyn PanelView>>,
+        Arc<
+            dyn Fn(
+                WeakView<DockArea>,
+                &DockItemState,
+                &DockItemInfo,
+                &mut WindowContext,
+            ) -> Box<dyn PanelView>,
+        >,
     >,
 }
 impl PanelRegistry {
@@ -160,7 +162,13 @@ impl Global for PanelRegistry {}
 /// Register the Panel init by panel_name to global registry.
 pub fn register_panel<F>(cx: &mut AppContext, panel_name: &str, deserialize: F)
 where
-    F: Fn(WeakView<DockArea>, DockItemInfo, &mut WindowContext) -> Box<dyn PanelView> + 'static,
+    F: Fn(
+            WeakView<DockArea>,
+            &DockItemState,
+            &DockItemInfo,
+            &mut WindowContext,
+        ) -> Box<dyn PanelView>
+        + 'static,
 {
     if let None = cx.try_global::<PanelRegistry>() {
         cx.set_global(PanelRegistry::new());

crates/ui/src/dock/stack_panel.rs

@@ -38,7 +38,7 @@ impl Panel for StackPanel {
 
     fn dump(&self, cx: &AppContext) -> DockItemState {
         let sizes = self.panel_group.read(cx).sizes();
-        let mut state = DockItemState::new(self.panel_name());
+        let mut state = DockItemState::new(self);
         for panel in &self.panels {
             state.add_child(panel.dump(cx));
             state.info = DockItemInfo::stack(sizes.clone(), self.axis);

crates/ui/src/dock/state.rs

@@ -4,13 +4,18 @@ use itertools::Itertools as _;
 use serde::{Deserialize, Serialize};
 
 use super::{
-    invalid_panel::InvalidPanel, Dock, DockArea, DockItem, DockPlacement, PanelRegistry, PanelView,
-    TabPanel,
+    invalid_panel::InvalidPanel, Dock, DockArea, DockItem, DockPlacement, Panel, PanelRegistry,
+    PanelView, TabPanel,
 };
 
 /// Used to serialize and deserialize the DockArea
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
 pub struct DockAreaState {
+    /// The version is used to mark this persisted state is compatible with the current version
+    /// For example, some times we many totally changed the structure of the Panel,
+    /// then we can compare the version to decide whether we can use the state or ignore.
+    #[serde(default)]
+    pub version: Option<usize>,
     pub center: DockItemState,
     pub left_dock: Option<DockState>,
     pub right_dock: Option<DockState>,
@@ -138,9 +143,9 @@ impl Default for DockItemState {
 }
 
 impl DockItemState {
-    pub fn new(panel_name: &str) -> Self {
+    pub fn new<P: Panel>(panel: &P) -> Self {
         Self {
-            panel_name: panel_name.to_string(),
+            panel_name: panel.panel_name().to_string(),
             ..Default::default()
         }
     }
@@ -192,7 +197,7 @@ impl DockItemState {
                     .get(&self.panel_name)
                     .cloned()
                 {
-                    f(dock_area.clone(), info.clone(), cx)
+                    f(dock_area.clone(), self, &info, cx)
                 } else {
                     // Show an invalid panel if the panel is not registered.
                     Box::new(
@@ -215,6 +220,7 @@ mod tests {
     fn test_deserialize_item_state() {
         let json = include_str!("../../tests/fixtures/layout.json");
         let state: DockAreaState = serde_json::from_str(json).unwrap();
+        assert_eq!(state.version, None);
         assert_eq!(state.center.panel_name, "StackPanel");
         assert_eq!(state.center.children.len(), 2);
         assert_eq!(state.center.children[0].panel_name, "TabPanel");

crates/ui/src/dock/tab_panel.rs

@@ -122,7 +122,7 @@ impl Panel for TabPanel {
     }
 
     fn dump(&self, cx: &AppContext) -> DockItemState {
-        let mut state = DockItemState::new(self.panel_name());
+        let mut state = DockItemState::new(self);
         for panel in self.panels.iter() {
             state.add_child(panel.dump(cx));
             state.info = DockItemInfo::tabs(self.active_ix);