Dock: LAYERS opens its pallet like Insert Block, Layer Manager layout fixes, 150 ms auto-hide hover delay

- LAYERS ribbon button runs a command that opens the Layer Manager pallet;
  the ribbon no longer keeps it highlighted.
- Layer Manager: search box stays right-aligned, the column header fills
  the row, no stray contour lines when the pallet is taller than its rows.
- Auto-hidden edges don't show the shown-group accent bar.
- Auto-hide reveal and hide wait 150 ms of rest, so passing over the
  strip doesn't flash groups open.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_013RyGiMXcsf9HTKfqDxaQGt

src/app/commands/fileops.rs

@@ -354,7 +354,9 @@ impl OpenCADStudio {
             "ORTHO" => return Some(Task::done(Message::ToggleOrtho)),
             "PARALLEL" => return Some(Task::done(Message::SetProjection(true))),
             "PERSP" => return Some(Task::done(Message::SetProjection(false))),
-            "LAYERS" => return Some(Task::done(Message::ToggleLayers)),
+            // LAYERS opens the Layer Manager pallet (its close button or
+            // the toggle message close it).
+            "LAYERS" => self.open_layers_pallet(),
 
             // SCRIPT <path> — run a command script: each non-comment
             // line is fed through the same command path the `--script` startup

src/app/dock/tests.rs

@@ -336,9 +336,19 @@ fn dock_hover_reveals_groups_only_on_an_auto_hiding_edge() {
     assert!(!app.dock_edge_expanded(DockSide::Left));
     // Hovering an icon flies its group out.
     let _ = app.on_dock(DockMsg::Hover(PanelId::Browser));
+    // ...but only once the pointer rests: the reveal waits for the delay.
+    assert!(!app.dock_edge_expanded(DockSide::Left));
+    let _ = app.on_dock(DockMsg::HoverSettled(app.dock_hover_gen));
     assert!(app.dock_edge_expanded(DockSide::Left));
     assert_eq!(app.dock_shown_group(DockSide::Left), Some(1));
+    // Leaving and coming back within the delay keeps it open.
     let _ = app.on_dock(DockMsg::HoverExit);
+    let stale = app.dock_hover_gen;
+    let _ = app.on_dock(DockMsg::HoverStay);
+    let _ = app.on_dock(DockMsg::HoverSettled(stale));
+    assert!(app.dock_edge_expanded(DockSide::Left));
+    let _ = app.on_dock(DockMsg::HoverExit);
+    let _ = app.on_dock(DockMsg::HoverSettled(app.dock_hover_gen));
     assert!(!app.dock_edge_expanded(DockSide::Left));
     // Without auto-hide, hovering does not switch groups (clicks do).
     let _ = app.on_dock(DockMsg::AutoCollapseToggle(PanelId::Properties));
@@ -539,12 +549,29 @@ fn hovering_a_strip_icon_reveals_an_auto_hiding_edge_in_the_real_view() {
         icon,
         &[iced::Event::Mouse(iced::mouse::Event::CursorMoved { position: icon })],
     );
+    let _ = app.on_dock(DockMsg::HoverSettled(app.dock_hover_gen));
     assert!(
         app.dock_edge_expanded(DockSide::Right),
         "hovering the icon reveals the auto-hiding edge"
     );
 }
 
+#[test]
+fn layers_ribbon_button_opens_the_pallet_without_staying_highlighted() {
+    let mut app = dock_app();
+    // The ribbon's LAYERS button runs the LAYERS command.
+    let click = || Message::RibbonToolClick {
+        tool_id: "LAYERS".to_string(),
+        event: crate::modules::ModuleEvent::Command("LAYERS".to_string()),
+    };
+    let _ = app.update(click());
+    assert!(app.show_layers);
+    assert_eq!(app.ribbon.active_tool(), None);
+    // Pressing it again keeps it open, like the Blocks palette's button.
+    let _ = app.update(click());
+    assert!(app.show_layers);
+}
+
 #[test]
 fn dock_double_clicks_float_and_dock_panels() {
     use crate::app::config::DockSide;

src/app/dock/update.rs

@@ -7,6 +7,24 @@ use crate::app::{Message, OpenCADStudio};
 /// so a plain click never moves anything.
 const DOCK_DRAG_THRESHOLD: f32 = 5.0;
 
+/// Resolves once the dock hover delay has passed (a sleeping helper thread;
+/// the web build has none and resolves at once).
+fn hover_delay() -> impl std::future::Future<Output = ()> {
+    #[cfg(not(target_arch = "wasm32"))]
+    let rx = {
+        let (tx, rx) = iced::futures::channel::oneshot::channel::<()>();
+        std::thread::spawn(move || {
+            std::thread::sleep(crate::ui::dock::DOCK_HOVER_DELAY);
+            let _ = tx.send(());
+        });
+        rx
+    };
+    async move {
+        #[cfg(not(target_arch = "wasm32"))]
+        let _ = rx.await;
+    }
+}
+
 impl OpenCADStudio {
     /// Dock chrome interaction (grab / pin / resize / hover / move) applied to
     /// whichever panel the message names.
@@ -126,11 +144,15 @@ impl OpenCADStudio {
             DockMsg::Hover(id) => {
                 self.dock_icon_hover = Some(id);
                 // Only an auto-hiding edge (or floating pallet) reacts to
-                // hover: it reveals the hovered pallet's group. Otherwise
-                // groups switch on click. Ignored mid-drag, when the pointer
-                // is over the preview rather than the strip.
+                // hover: after a short rest it reveals the hovered pallet's
+                // group. Otherwise groups switch on click. Ignored mid-drag,
+                // when the pointer is over the preview rather than the strip.
                 if self.dock_drag.is_none() && self.dock.auto_hides(id) {
-                    self.dock_reveal(id);
+                    if self.dock_peek == Some(id) {
+                        self.dock_hover_cancel();
+                    } else {
+                        return self.dock_hover_arm(Some(id));
+                    }
                 }
             }
             DockMsg::HoverEnd(id) => {
@@ -142,7 +164,25 @@ impl OpenCADStudio {
                 if self.dock_drag.is_none()
                     && self.dock_peek.is_some_and(|id| self.dock.auto_hides(id))
                 {
-                    self.dock_peek = None;
+                    return self.dock_hover_arm(None);
+                }
+                // Left before a pending reveal ran out: it never happens.
+                self.dock_hover_cancel();
+            }
+            DockMsg::HoverStay => {
+                if self.dock_hover_pending == Some(None) {
+                    self.dock_hover_cancel();
+                }
+            }
+            DockMsg::HoverSettled(gen) => {
+                if gen == self.dock_hover_gen && self.dock_drag.is_none() {
+                    match self.dock_hover_pending.take() {
+                        Some(Some(id)) if self.dock.auto_hides(id) => self.dock_reveal(id),
+                        Some(None) if self.dock_peek.is_some_and(|id| self.dock.auto_hides(id)) => {
+                            self.dock_peek = None;
+                        }
+                        _ => {}
+                    }
                 }
             }
             DockMsg::DragMove(point) => self.dock_drag_move(point),
@@ -329,6 +369,23 @@ impl OpenCADStudio {
 
     /// Bring `id` into view: show its group on its edge and, where it
     /// auto-hides, keep it revealed until the pointer leaves.
+    /// Arm a delayed reveal (`Some`) or hide (`None`); it applies when its
+    /// timer reports back unless a newer hover superseded it.
+    fn dock_hover_arm(&mut self, target: Option<crate::ui::dock::PanelId>) -> iced::Task<Message> {
+        self.dock_hover_gen = self.dock_hover_gen.wrapping_add(1);
+        self.dock_hover_pending = Some(target);
+        let gen = self.dock_hover_gen;
+        iced::Task::perform(hover_delay(), move |()| {
+            Message::Dock(crate::ui::dock::DockMsg::HoverSettled(gen))
+        })
+    }
+
+    /// Drop any pending delayed reveal / hide.
+    fn dock_hover_cancel(&mut self) {
+        self.dock_hover_gen = self.dock_hover_gen.wrapping_add(1);
+        self.dock_hover_pending = None;
+    }
+
     pub(crate) fn dock_reveal(&mut self, id: crate::ui::dock::PanelId) {
         self.dock.show_group_of(id);
         self.dock_peek = Some(id);
@@ -419,6 +476,29 @@ impl OpenCADStudio {
         self.dock_reveal(id);
     }
 
+    /// Open the Layer Manager pallet (LAYERS). The first time it floats over
+    /// the middle of the drawing, where the dialog it replaced used to open;
+    /// after that it opens wherever the user left it.
+    pub(crate) fn open_layers_pallet(&mut self) {
+        use crate::ui::dock::{FloatPanel, PanelId};
+        self.sync_ribbon_layers();
+        self.show_layers = true;
+        if !self.dock.is_placed(PanelId::Layers) {
+            let (ww, wh) = self.dock_workspace_size();
+            let (w, h) = self.dock_float_size(PanelId::Layers);
+            self.dock.float(FloatPanel {
+                id: PanelId::Layers,
+                x: ((ww - w) * 0.5).max(0.0),
+                y: ((wh - h) * 0.5).max(0.0),
+                w,
+                h,
+            });
+            self.save_config();
+        }
+        self.dock.raise_float(PanelId::Layers);
+        self.dock_reveal(PanelId::Layers);
+    }
+
     /// Stop revealing `id` (it closed).
     pub(crate) fn dock_unpeek(&mut self, id: crate::ui::dock::PanelId) {
         if self.dock_peek == Some(id) {

src/app/dock/view.rs

@@ -147,6 +147,7 @@ impl OpenCADStudio {
         }
         Some(
             mouse_area(row(children).height(Fill))
+                .on_enter(Message::Dock(crate::ui::dock::DockMsg::HoverStay))
                 .on_exit(Message::Dock(crate::ui::dock::DockMsg::HoverExit))
                 .into(),
         )
@@ -165,7 +166,11 @@ impl OpenCADStudio {
             DockMsg, DropTarget, DOCK_STRIP_W, STRIP_CELL_H, STRIP_DIVIDER_H, STRIP_GRIP_W,
             STRIP_PAD, STRIP_PLUS_GAP,
         };
-        let shown = self.dock_shown_group(side);
+        // Only a group actually on screen is marked as shown: on an
+        // auto-hiding edge nothing is, until a group is revealed.
+        let shown = self
+            .dock_shown_group(side)
+            .filter(|_| self.dock_edge_expanded(side));
         let movement = self.dock_drag.and_then(|d| d.movement());
         let move_target = movement.and_then(|(_, _, target)| target);
         let dragging = move_target.is_some();

src/app/mod.rs

@@ -850,6 +850,10 @@ pub(super) struct OpenCADStudio {
     /// floating frame): hovered, being dragged, or just opened. Cleared when
     /// the pointer leaves.
     pub(crate) dock_peek: Option<crate::ui::dock::PanelId>,
+    /// Reveal (`Some(pallet)`) or hide (`None`) waiting out the hover delay,
+    /// with the generation its timer carries; any newer hover supersedes it.
+    pub(crate) dock_hover_pending: Option<Option<crate::ui::dock::PanelId>>,
+    pub(crate) dock_hover_gen: u64,
     /// What the pointer is dragging in the dock (pallet, group, width,
     /// splitter, floating size, Layer Manager column).
     pub(crate) dock_drag: Option<crate::ui::dock::DockDrag>,
@@ -4291,6 +4295,8 @@ impl OpenCADStudio {
             xref_manager: Default::default(),
             dock: Default::default(),
             dock_peek: None,
+            dock_hover_pending: None,
+            dock_hover_gen: 0,
             dock_drag: None,
             dock_drag_last: None,
             dock_title_hover: None,

src/app/update/mod.rs

@@ -2552,28 +2552,12 @@ impl OpenCADStudio {
             Message::ScriptLine(line) => self.feed_script_line(&line),
 
             Message::ToggleLayers => {
-                use crate::ui::dock::PanelId;
                 if self.show_layers {
-                    return self.on_dock(crate::ui::dock::DockMsg::Close(PanelId::Layers));
+                    return self.on_dock(crate::ui::dock::DockMsg::Close(
+                        crate::ui::dock::PanelId::Layers,
+                    ));
                 }
-                self.sync_ribbon_layers();
-                self.show_layers = true;
-                if !self.dock.is_placed(PanelId::Layers) {
-                    // First use: float it over the middle of the drawing,
-                    // where the dialog used to open.
-                    let (ww, wh) = self.dock_workspace_size();
-                    let (w, h) = self.dock_float_size(PanelId::Layers);
-                    self.dock.float(crate::ui::dock::FloatPanel {
-                        id: PanelId::Layers,
-                        x: ((ww - w) * 0.5).max(0.0),
-                        y: ((wh - h) * 0.5).max(0.0),
-                        w,
-                        h,
-                    });
-                    self.save_config();
-                }
-                self.dock.raise_float(PanelId::Layers);
-                self.dock_reveal(PanelId::Layers);
+                self.open_layers_pallet();
                 Task::none()
             }
 

src/modules/draw/layers/panel.rs

@@ -1,4 +1,4 @@
-// Layers panel toggle — ribbon definition.
+// Layer Manager pallet — ribbon definition.
 
 use crate::modules::{IconKind, ModuleEvent, ToolDef};
 
@@ -7,6 +7,8 @@ pub fn tool() -> ToolDef {
         id: "LAYERS",
         label: "Layers",
         icon: IconKind::Svg(include_bytes!("../../../../assets/icons/layers/panel.svg")),
-        event: ModuleEvent::ToggleLayers,
+        // A command like the Blocks palette's: it opens the pallet, and the
+        // ribbon drops the button's highlight once it has run.
+        event: ModuleEvent::Command("LAYERS".to_string()),
     }
 }

src/ui/dock.rs

@@ -71,8 +71,16 @@ pub enum DockMsg {
     FloatRaise(PanelId),
     /// The pointer left the edge column; collapse any auto-collapsing panel.
     HoverExit,
+    /// The pointer entered the edge column again: keep its group revealed.
+    HoverStay,
+    /// The hover delay of the reveal / hide armed as generation `n` ran out.
+    HoverSettled(u64),
 }
 
+/// How long the pointer must rest before an auto-hiding group reveals or
+/// hides, so passing over the strip doesn't flash groups open.
+pub const DOCK_HOVER_DELAY: std::time::Duration = std::time::Duration::from_millis(150);
+
 /// The dockable panels the application knows about. New palettes add a variant.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
 #[serde(rename_all = "snake_case")]

src/ui/window/layers.rs

@@ -323,8 +323,9 @@ impl LayerPanel {
         self.linetype_items = items;
     }
 
-    /// The Layer Manager as a dock pallet: its title bar, then the table at
-    /// its natural width, scrolling sideways when the pallet is narrower.
+    /// The Layer Manager as a dock pallet: its title bar, the toolbar across
+    /// the pallet (search box on the right), then the table, at least as wide
+    /// as the pallet and scrolling sideways when the pallet is narrower.
     pub fn view_panel(
         &self,
         name_col_w: f32,
@@ -337,19 +338,8 @@ impl LayerPanel {
             crate::tr!("modal", "layer-manager"),
             chrome,
         );
-        let table = self.view_content(
-            name_col_w,
-            crate::ui::modal::ModalSizing {
-                width: Length::Shrink,
-                height: Length::Fill,
-            },
-        );
-        let body = scrollable(table)
-            .direction(iced::widget::scrollable::Direction::Horizontal(
-                iced::widget::scrollable::Scrollbar::new(),
-            ))
-            .width(Length::Fill)
-            .height(Length::Fill);
+        // Inside the pallet's 1 px border on either side.
+        let body = self.view_content(name_col_w, (width - 2.0).max(0.0));
         container(column![title_bar, body])
             .width(Length::Fixed(width))
             .height(Length::Fill)
@@ -365,11 +355,8 @@ impl LayerPanel {
             .into()
     }
 
-    fn view_content(
-        &self,
-        name_col_w: f32,
-        sizing: crate::ui::modal::ModalSizing,
-    ) -> Element<'_, Message> {
+    /// Toolbar and table for a pallet `inner_w` wide.
+    fn view_content(&self, name_col_w: f32, inner_w: f32) -> Element<'_, Message> {
         let has_sel = self.selected.is_some();
         let sel_is_zero = self
             .selected
@@ -396,7 +383,7 @@ impl LayerPanel {
                     Message::LayerSetCurrent,
                     can_set_current,
                 ),
-                iced::widget::Space::new().width(sizing.width),
+                iced::widget::Space::new().width(Length::Fill),
                 // Search box: filters rows by name as the user types (#343).
                 text_input(t!("Search…").as_ref(), &self.filter)
                     .on_input(Message::LayerManagerFilterChanged)
@@ -414,7 +401,7 @@ impl LayerPanel {
             )),
             ..Default::default()
         })
-        .width(sizing.width)
+        .width(Length::Fill)
         .padding([4, 8]);
 
         // ── Column header ─────────────────────────────────────────────────
@@ -452,7 +439,6 @@ impl LayerPanel {
             ),
         ]
         .spacing(4)
-        .width(sizing.width)
         .align_y(iced::Center);
 
         for vp in &self.vp_cols {
@@ -478,7 +464,7 @@ impl LayerPanel {
                 }
             })
             .padding([4, 8])
-            .width(sizing.width);
+            .width(Length::Fill);
 
         // ── Layer rows ────────────────────────────────────────────────────
         let mut rows_col = column![].spacing(0);
@@ -519,19 +505,26 @@ impl LayerPanel {
 
         let table = scrollable(rows_col)
             .id(iced::advanced::widget::Id::new(LAYER_TABLE_SCROLL_ID))
-            .height(sizing.height.min(240.0));
+            .width(Length::Fill)
+            .height(Length::Fill);
 
-        // ── Full-window frame ─────────────────────────────────────────────
-        container(column![toolbar, col_header, table].spacing(0))
-            .style(|theme: &Theme| container::Style {
-                background: Some(Background::Color(
-                    theme.palette().background.base.color
-                )),
-                ..Default::default()
-            })
-            .width(sizing.width)
-            .height(sizing.height)
-            .into()
+        // The header and table stretch to the wider of their columns and the
+        // pallet (the zero-height spacer), so the header's grey band and
+        // borders always run to the pallet's edge; a narrower pallet scrolls
+        // the table sideways while the toolbar stays put.
+        let grid = column![
+            col_header,
+            table,
+            iced::widget::Space::new().width(Length::Fixed(inner_w)).height(0),
+        ]
+        .height(Length::Fill);
+        let grid = scrollable(grid)
+            .direction(iced::widget::scrollable::Direction::Horizontal(
+                iced::widget::scrollable::Scrollbar::new(),
+            ))
+            .width(Length::Fill)
+            .height(Length::Fill);
+        column![toolbar, grid].height(Length::Fill).into()
     }
 }