WindowManager: Explicitly override window group of shell windows

Author: leolost2605

src/ShellClients/ShellClientsManager.vala

@@ -8,7 +8,7 @@
 public class Gala.ShellClientsManager : Object, GestureTarget {
     private static ShellClientsManager instance;
 
-    public static void init (WindowManager wm) {
+    public static void init (WindowManagerGala wm) {
         if (instance != null) {
             return;
         }
@@ -20,7 +20,7 @@ public class Gala.ShellClientsManager : Object, GestureTarget {
         return instance;
     }
 
-    public WindowManager wm { get; construct; }
+    public WindowManagerGala wm { get; construct; }
 
     private NotificationsClient notifications_client;
     private ManagedClient[] protocol_clients = {};
@@ -31,7 +31,7 @@ public class Gala.ShellClientsManager : Object, GestureTarget {
     private GLib.HashTable<Meta.Window, ExtendedBehaviorWindow> positioned_windows = new GLib.HashTable<Meta.Window, ExtendedBehaviorWindow> (null, null);
     private GLib.HashTable<Meta.Window, MonitorLabelWindow> monitor_label_windows = new GLib.HashTable<Meta.Window, MonitorLabelWindow> (null, null);
 
-    private ShellClientsManager (WindowManager wm) {
+    private ShellClientsManager (WindowManagerGala wm) {
         Object (wm: wm);
     }
 
@@ -178,6 +178,8 @@ public class Gala.ShellClientsManager : Object, GestureTarget {
 
         panel_windows[window] = new PanelWindow (wm, window, anchor);
 
+        wm.override_window_group (window, DESKTOP_SHELL);
+
         InternalUtils.wait_for_window_actor_visible (window, on_panel_ready);
 
         // connect_after so we make sure the PanelWindow can destroy its barriers and struts
@@ -243,6 +245,8 @@ public class Gala.ShellClientsManager : Object, GestureTarget {
 
     public void make_modal (Meta.Window window, bool dim) requires (window in positioned_windows) {
         positioned_windows[window].make_modal (dim);
+
+        wm.override_window_group (window, MODAL);
     }
 
     public void make_monitor_label (Meta.Window window, int monitor_index) requires (!is_itself_shell_window (window)) {
@@ -253,6 +257,8 @@ public class Gala.ShellClientsManager : Object, GestureTarget {
 
         monitor_label_windows[window] = new MonitorLabelWindow (window, monitor_index);
 
+        wm.override_window_group (window, DESKTOP_SHELL);
+
         // connect_after so we make sure that any queued move is unqueued
         window.unmanaging.connect_after ((_window) => monitor_label_windows.remove (_window));
     }
@@ -297,25 +303,10 @@ public class Gala.ShellClientsManager : Object, GestureTarget {
         return positioned;
     }
 
-    private bool is_itself_system_modal (Meta.Window window) {
-        return (window in positioned_windows) && positioned_windows[window].modal;
-    }
-
-    public bool is_system_modal_window (Meta.Window window) {
-        var modal = is_itself_system_modal (window);
-        window.foreach_ancestor ((ancestor) => {
-            if (is_itself_system_modal (ancestor)) {
-                modal = true;
-            }
-
-            return !modal;
-        });
-
-        return modal;
-    }
-
-    public bool is_system_modal_dimmed (Meta.Window window) {
-        return is_itself_system_modal (window) && positioned_windows[window].dim;
+    public bool is_system_modal_dimmed (Meta.Window window) requires (
+        window in positioned_windows && positioned_windows[window].modal
+    ) {
+        return positioned_windows[window].dim;
     }
 
     //X11 only

src/WindowManager.vala

@@ -18,6 +18,11 @@
 
 namespace Gala {
     public class WindowManagerGala : Meta.Plugin, WindowManager {
+        public enum WindowGroup {
+            DESKTOP_SHELL,
+            MODAL,
+        }
+
         private const string OPEN_MULTITASKING_VIEW = "dbus-send --session --dest=org.pantheon.gala --print-reply /org/pantheon/gala org.pantheon.gala.PerformAction int32:1";
         private const string OPEN_APPLICATIONS_MENU = "io.elementary.wingpanel --toggle-indicator=app-launcher";
 
@@ -120,6 +125,8 @@ namespace Gala {
 
         private GLib.Settings behavior_settings;
 
+        private Gee.Map<Meta.Window, WindowGroup> overridden_window_group = new Gee.HashMap<Meta.Window, WindowGroup> ();
+
         construct {
 #if !HAS_MUTTER48
             info = Meta.PluginInfo () {name = "Gala", version = Config.VERSION, author = "Gala Developers",
@@ -1040,23 +1047,57 @@ namespace Gala {
             show_window_menu (window, menu, rect.x, rect.y);
         }
 
+        /**
+         * Tells the wm to place the {@link window} in the given {@link new_group} instead of the default
+         * window group as determined by the wm.
+         * The wm will also automatically place transient windows of {@link window} in the same group.
+         */
+        public void override_window_group (Meta.Window window, WindowGroup new_group) {
+            overridden_window_group[window] = new_group;
+            window.unmanaged.connect ((_window) => overridden_window_group.unset (_window));
+
+            InternalUtils.wait_for_window_actor_visible (window, (actor) => {
+                InternalUtils.clutter_actor_reparent (actor, get_window_group_actor (new_group));
+
+                // FIXME: workaround for https://github.com/elementary/dock/issues/537
+                actor.set_scale (1.0, 1.0);
+                actor.opacity = 255;
+            });
+        }
+
+        private Clutter.Actor get_window_group_actor (WindowGroup group) {
+            switch (group) {
+                case DESKTOP_SHELL: return shell_group;
+                case MODAL: return modal_group.window_group;
+                default: assert_not_reached ();
+            }
+        }
+
         private void check_shell_window (Meta.WindowActor actor) {
             unowned var window = actor.get_meta_window ();
 
-            if (ShellClientsManager.get_instance ().is_system_modal_window (window)) {
-                InternalUtils.clutter_actor_reparent (actor, modal_group.window_group);
+            if (overridden_window_group.has_key (window)) {
+                /* We are already overridden so make sure to ignore it */
                 return;
             }
 
-            if (ShellClientsManager.get_instance ().is_shell_window (window)) {
-                InternalUtils.clutter_actor_reparent (actor, shell_group);
+            /* Check if we're a transient of a window with an overridden group and if so place there */
+            window.foreach_ancestor ((ancestor) => {
+                if (overridden_window_group.has_key (ancestor)) {
+                    override_window_group (window, overridden_window_group[ancestor]);
+                    return false;
+                }
+
+                return true;
+            });
 
-                // FIXME: workaround for https://github.com/elementary/dock/issues/537
-                actor.set_scale (1.0, 1.0);
-                actor.opacity = 255;
+            if (overridden_window_group.has_key (window)) {
+                /* We found an ancestor with an overridden group so we are now being placed in the same group */
+                return;
             }
 
             if (NotificationStack.is_notification (window)) {
+                override_window_group (window, DESKTOP_SHELL);
                 notification_stack.show_notification (actor);
             }