Implement support for keeping shellclients in the multitasking view

lib/DragDropAction.vala

@@ -55,6 +55,15 @@ namespace Gala {
          */
         public signal void destination_crossed (Clutter.Actor destination, bool hovered);
 
+        /**
+         * Emitted on the source when we are hovering over a destination.
+         *
+         * @param destination The destination actor that we are hovering over
+         * @param x           The x coordinate relative to the destination actor
+         * @param y           The y coordinate relative to the destination actor
+         */
+        public signal void destination_motion (Clutter.Actor destination, float x, float y);
+
         /**
          * The source has been clicked, but the movement was not larger than
          * the drag threshold. Useful if the source is also activatable.
@@ -341,7 +350,7 @@ namespace Gala {
                         last_y = y;
 
                         var stage = actor.get_stage ();
-                        var actor = stage.get_actor_at_pos (Clutter.PickMode.REACTIVE, (int) x, (int) y);
+                        var actor = stage.get_actor_at_pos (NONE, (int) x, (int) y);
                         DragDropAction action = null;
                         // if we're allowed to bubble and this actor is not a destination, check its parents
                         if (actor != null && (action = get_drag_drop_action (actor)) == null && allow_bubbling) {
@@ -352,8 +361,12 @@ namespace Gala {
                         }
 
                         // didn't change, no need to do anything
-                        if (actor == hovered)
+                        if (actor == hovered) {
+                            if (hovered != null) {
+                                destination_motion (hovered, x - hovered.x, y - hovered.y);
+                            }
                             return Clutter.EVENT_STOP;
+                        }
 
                         if (action == null) {
                             // apparently we left ours if we had one before
@@ -436,12 +449,12 @@ namespace Gala {
         }
 
         private void finish () {
+            drag_end (hovered);
+
             // make sure they reset the style or whatever they changed when hovered
             emit_crossed (hovered, false);
 
             cleanup ();
-
-            drag_end (hovered);
         }
 
         private void cleanup () {

lib/WindowManager.vala

@@ -139,13 +139,20 @@ namespace Gala {
         public abstract Meta.BackgroundGroup background_group { get; protected set; }
 
         /**
-         * Enters the modal mode, which means that all events are directed to the stage instead
-         * of the windows. This is the only way to receive keyboard events besides shortcut listeners.
+         * Enters the modal mode, which will block keybindings and gestures. See {@link ModalProxy} for
+         * how to allow certain gestures and keybindings.
+         * If {@link grab} is true all events will be redirected to the given {@link Clutter.Actor}.
+         * If {@link grab} is false other actors and shell windows may still receive events.
+         * Normal windows will never receive keyboard focus though they will still receive pointer events
+         * if {@link grab} is false and their {@link Meta.WindowActor} is visible.
+         *
+         * @param actor The actor to grab events for
+         * @param grab Whether to grab all events onto the actor
          *
          * @return a {@link ModalProxy} which is needed to end the modal mode again and provides some
          *         some basic control on the behavior of the window manager while it is in modal mode.
          */
-        public abstract ModalProxy push_modal (Clutter.Actor actor);
+        public abstract ModalProxy push_modal (Clutter.Actor actor, bool grab);
 
         /**
          * May exit the modal mode again, unless another component has called {@link push_modal}

plugins/pip/SelectionArea.vala

@@ -126,7 +126,7 @@ public class Gala.Plugins.PIP.SelectionArea : CanvasActor {
         wm.get_display ().set_cursor (Meta.Cursor.CROSSHAIR);
         grab_key_focus ();
 
-        modal_proxy = wm.push_modal (this);
+        modal_proxy = wm.push_modal (this, true);
     }
 
     private void get_selection_rectangle (out int x, out int y, out int width, out int height) {

po/POTFILES

@@ -82,18 +82,14 @@ src/ShellClients/NotificationsClient.vala
 src/ShellClients/PanelWindow.vala
 src/ShellClients/ShellClientsManager.vala
 src/Widgets/DwellClickTimer.vala
-src/Widgets/MultitaskingView/IconGroup.vala
-src/Widgets/MultitaskingView/IconGroupContainer.vala
 src/Widgets/MultitaskingView/MonitorClone.vala
 src/Widgets/MultitaskingView/MultitaskingView.vala
 src/Widgets/MultitaskingView/StaticWindowClone.vala
 src/Widgets/MultitaskingView/StaticWindowContainer.vala
 src/Widgets/MultitaskingView/Tooltip.vala
 src/Widgets/MultitaskingView/WindowClone.vala
 src/Widgets/MultitaskingView/WindowCloneContainer.vala
-src/Widgets/MultitaskingView/WindowIconActor.vala
 src/Widgets/MultitaskingView/WorkspaceClone.vala
-src/Widgets/MultitaskingView/WorkspaceInsertThumb.vala
 src/Widgets/MultitaskingView/WorkspaceRow.vala
 src/Widgets/PixelPicker.vala
 src/Widgets/PointerLocator.vala

protocol/pantheon-desktop-shell-v1.xml

@@ -98,6 +98,12 @@
 
       <arg name="hide_mode" type="uint" enum="hide_mode" summary="hide mode"/>
     </request>
+
+    <request name="request_visible_in_multitasking_view">
+      <description summary="request visible in multitasking view">
+        Tell the shell that the panel would like to be visible in the multitasking view.
+      </description>
+    </request>
   </interface>
 
   <interface name="io_elementary_pantheon_widget_v1" version="1">

protocol/pantheon-desktop-shell.vapi

@@ -41,6 +41,7 @@ namespace Pantheon.Desktop {
         public Focus focus;
         public SetSize set_size;
         public SetHideMode set_hide_mode;
+        public RequestVisibleInMultitaskingView request_visible_in_multitasking_view;
     }
 
     [CCode (cheader_filename = "pantheon-desktop-shell-server-protocol.h", cname = "struct io_elementary_pantheon_widget_v1_interface")]
@@ -75,6 +76,8 @@ namespace Pantheon.Desktop {
     [CCode (has_target = false, has_typedef = false)]
     public delegate void SetHideMode (Wl.Client client, Wl.Resource resource, [CCode (type = "uint32_t")] HideMode hide_mode);
     [CCode (has_target = false, has_typedef = false)]
+    public delegate void RequestVisibleInMultitaskingView (Wl.Client client, Wl.Resource resource);
+    [CCode (has_target = false, has_typedef = false)]
     public delegate void SetKeepAbove (Wl.Client client, Wl.Resource resource);
     [CCode (has_target = false, has_typedef = false)]
     public delegate void MakeCentered (Wl.Client client, Wl.Resource resource);

src/DBus.vala

@@ -14,6 +14,19 @@ public class Gala.DBus {
     public static void init (WindowManagerGala _wm, NotificationsManager notifications_manager, ScreenshotManager screenshot_manager) {
         wm = _wm;
 
+        Bus.own_name (
+            SESSION, "io.elementary.gala", NONE,
+            (connection) => {
+                try {
+                    connection.register_object ("/io/elementary/gala", WindowDragProvider.get_instance ());
+                } catch (Error e) {
+                    warning (e.message);
+                }
+            },
+            () => {},
+            () => critical ("Could not acquire name")
+        );
+
         Bus.own_name (BusType.SESSION, "org.pantheon.gala", BusNameOwnerFlags.NONE,
             (connection) => {
                 if (instance == null)

src/DesktopIntegration.vala

@@ -143,19 +143,31 @@ public class Gala.DesktopIntegration : GLib.Object {
         return (owned) returned_windows;
     }
 
-    public void focus_window (uint64 uid) throws GLib.DBusError, GLib.IOError {
+    private Meta.Window find_window_by_uid (uint64 uid) throws IOError {
         var apps = Gala.AppSystem.get_default ().get_running_apps ();
         foreach (unowned var app in apps) {
             foreach (weak Meta.Window window in app.get_windows ()) {
                 if (window.get_id () == uid) {
-                    if (window.has_focus ()) {
-                        notify_already_focused (window);
-                    } else {
-                        window.get_workspace ().activate_with_focus (window, wm.get_display ().get_current_time ());
-                    }
+                    return window;
                 }
             }
         }
+
+        throw new IOError.NOT_FOUND ("Window with UID " + uid.to_string () + " not found");
+    }
+
+    public void focus_window (uint64 uid) throws GLib.DBusError, GLib.IOError {
+        var window = find_window_by_uid (uid);
+        if (window.has_focus ()) {
+            notify_already_focused (window);
+        } else {
+            window.get_workspace ().activate_with_focus (window, wm.get_display ().get_current_time ());
+        }
+    }
+
+    public void move_window_to_workspace (uint64 uid, int index) throws DBusError, IOError {
+        var window = find_window_by_uid (uid);
+        window.change_workspace_by_index (index, false);
     }
 
     public void activate_workspace (int index) throws GLib.DBusError, GLib.IOError {

src/InternalUtils.vala

@@ -9,6 +9,7 @@ namespace Gala {
     public enum InputArea {
         NONE,
         FULLSCREEN,
+        MULTITASKING_VIEW,
         DEFAULT
     }
 
@@ -32,6 +33,36 @@ namespace Gala {
                     rects = {rect};
                     break;
 
+                case InputArea.MULTITASKING_VIEW:
+                    var shell_client_rect = ShellClientsManager.get_instance ().get_shell_client_rect ();
+
+                    int width, height;
+                    display.get_size (out width, out height);
+
+                    if (shell_client_rect != null) {
+                        X.Xrectangle left_rect = {0, 0, (ushort) shell_client_rect.x, (ushort) height};
+                        X.Xrectangle right_rect = {
+                            (short) (shell_client_rect.x + shell_client_rect.width), 0,
+                            (ushort) (width - shell_client_rect.x - shell_client_rect.width), (ushort) height
+                        };
+                        X.Xrectangle top_rect = {
+                            (short) shell_client_rect.x, 0,
+                            (ushort) shell_client_rect.width, (ushort) shell_client_rect.y
+                        };
+                        X.Xrectangle bottom_rect = {
+                            (short) shell_client_rect.x,
+                            (short) (shell_client_rect.y + shell_client_rect.height),
+                            (ushort) shell_client_rect.width,
+                            (ushort) (height - shell_client_rect.y - shell_client_rect.height)
+                        };
+                        rects = {left_rect, right_rect, top_rect, bottom_rect};
+                    } else {
+                        X.Xrectangle rect = {0, 0, (ushort)width, (ushort)height};
+                        rects = {rect};
+                    }
+
+                    break;
+
                 case InputArea.DEFAULT:
                     // add plugin's requested areas
                     foreach (var rect in PluginManager.get_default ().get_regions ()) {
@@ -159,5 +190,40 @@ namespace Gala {
             var is_in_fullscreen = display.get_monitor_in_fullscreen (primary_monitor);
             return !Meta.Util.is_wayland_compositor () && is_in_fullscreen;
         }
+
+        /**
+         * Returns the most recently used "normal" window (as gotten via {@link get_window_is_normal}) in the given workspace.
+         * If there is a not normal but more recent window (e.g. a menu/tooltip) any_window will be set to that window otherwise
+         * it will be set to the same window that is returned.
+         */
+        public static Meta.Window? get_mru_window (Meta.Workspace workspace, out Meta.Window? any_window = null) {
+            any_window = null;
+
+            var list = workspace.list_windows ();
+
+            if (list.is_empty ()) {
+                return null;
+            }
+
+            list.sort ((a, b) => {
+                return (int) b.get_user_time () - (int) a.get_user_time ();
+            });
+
+            foreach (var window in list) {
+                if (!ShellClientsManager.get_instance ().is_positioned_window (window)) {
+                    if (any_window == null) {
+                        any_window = window;
+                    }
+
+                    if (!Utils.get_window_is_normal (window)) {
+                        continue;
+                    }
+
+                    return window;
+                }
+            }
+
+            return null;
+        }
     }
 }

src/PantheonShell.vala

@@ -39,6 +39,7 @@ namespace Gala {
             focus_panel,
             set_size,
             set_hide_mode,
+            request_visible_in_multitasking_view,
         };
 
         wayland_pantheon_widget_interface = {
@@ -292,6 +293,23 @@ namespace Gala {
         ShellClientsManager.get_instance ().set_hide_mode (window, hide_mode);
     }
 
+    internal static void request_visible_in_multitasking_view (Wl.Client client, Wl.Resource resource) {
+        unowned PanelSurface? panel_surface = resource.get_user_data<PanelSurface> ();
+        if (panel_surface.wayland_surface == null) {
+            warning ("Window tried to set visible in multitasking view but wayland surface is null.");
+            return;
+        }
+
+        Meta.Window? window;
+        panel_surface.wayland_surface.get ("window", out window, null);
+        if (window == null) {
+            warning ("Window tried to set visible in multitasking view but wayland surface had no associated window.");
+            return;
+        }
+
+        ShellClientsManager.get_instance ().request_visible_in_multitasking_view (window);
+    }
+
     internal static void set_keep_above (Wl.Client client, Wl.Resource resource) {
         unowned ExtendedBehaviorSurface? eb_surface = resource.get_user_data<ExtendedBehaviorSurface> ();
         if (eb_surface.wayland_surface == null) {

src/ShellClients/HideTracker.vala

@@ -153,7 +153,12 @@ public class Gala.HideTracker : Object {
         focus_maximized_overlap = false;
         fullscreen_overlap = display.get_monitor_in_fullscreen (panel.window.get_monitor ());
 
-        foreach (var window in display.get_workspace_manager ().get_active_workspace ().list_windows ()) {
+        unowned var active_workspace = display.get_workspace_manager ().get_active_workspace ();
+
+        Meta.Window? normal_mru_window, any_mru_window;
+        normal_mru_window = InternalUtils.get_mru_window (active_workspace, out any_mru_window);
+
+        foreach (var window in active_workspace.list_windows ()) {
             if (window == panel.window) {
                 continue;
             }
@@ -173,7 +178,7 @@ public class Gala.HideTracker : Object {
 
             overlap = true;
 
-            if (window != display.focus_window) {
+            if (window != normal_mru_window && window != any_mru_window) {
                 continue;
             }
 

src/ShellClients/PanelWindow.vala

@@ -61,6 +61,11 @@ public class Gala.PanelWindow : ShellWindow, RootTarget {
         hide_tracker.show.connect (show);
     }
 
+    public void request_visible_in_multitasking_view () {
+        visible_in_multitasking_view = true;
+        actor.add_action (new DragDropAction (DESTINATION, "multitaskingview-window"));
+    }
+
     private void hide () {
         gesture_controller.goto (1);
     }

src/ShellClients/ShellClientsManager.vala

@@ -185,6 +185,15 @@ public class Gala.ShellClientsManager : Object, GestureTarget {
         panel_windows[window].hide_mode = hide_mode;
     }
 
+    public void request_visible_in_multitasking_view (Meta.Window window) {
+        if (!(window in panel_windows)) {
+            warning ("Set anchor for window before visible in mutltiasking view.");
+            return;
+        }
+
+        panel_windows[window].request_visible_in_multitasking_view ();
+    }
+
     public void make_centered (Meta.Window window) requires (!is_itself_positioned (window)) {
         positioned_windows[window] = new ShellWindow (window, CENTER);
 
@@ -290,6 +299,10 @@ public class Gala.ShellClientsManager : Object, GestureTarget {
                     }
                     break;
 
+                case "visible-in-multitasking-view":
+                    request_visible_in_multitasking_view (window);
+                    break;
+
                 case "centered":
                     make_centered (window);
                     break;
@@ -309,4 +322,13 @@ public class Gala.ShellClientsManager : Object, GestureTarget {
     requires (window in panel_windows) {
         panel_windows[window].restore_previous_x11_region = true;
     }
+
+    public Mtk.Rectangle? get_shell_client_rect () {
+        foreach (var client in panel_windows.get_values ()) {
+            if (client.visible_in_multitasking_view) {
+                return client.get_custom_window_rect ();
+            }
+        }
+        return null;
+    }
 }