windowManager: Block dynamic workspace updates while showing the popup

Pause dynamic workspace management while workspaceSwitcherPopup
is shown so as to eliminate infinite creation and destruction of
workspaces, thus preventing stuttering while trying to move a
window to last workspace.
Add _isWorkspacePrepended flag to make sure only a single workspace
is prepended at a time thus preventing the possibility of prepending
infinite workspaces while dynamic workspace management is on pause.
Prepend a new workspace by creating a new workspace instead of only
shifting the windows to next workspace so that the workspaceSwitcherPopup
may appear in sync with what's happening behind the scene and display
correct number of workspaces.

https://bugzilla.gnome.org/show_bug.cgi?id=712778

diff --git a/js/ui/windowManager.js b/js/ui/windowManager.js
index bdde74637238f1f91513124f74c5370e176f2208..01d510736f86a4488fe46ebe7736a599845215e4 100644 (file)
--- a/js/ui/windowManager.js
+++ b/js/ui/windowManager.js
@@ -197,6 +197,8 @@ const WorkspaceTracker = new Lang.Class({
         this._workspaces = [];
         this._checkWorkspacesId = 0;
 
+        this._pauseWorkspaceCheck = false;
+
         let tracker = Shell.WindowTracker.get_default();
         tracker.connect('startup-sequence-changed', Lang.bind(this, this._queueCheckWorkspaces));
 
@@ -220,6 +222,14 @@ const WorkspaceTracker = new Lang.Class({
         return new Gio.Settings({ schema_id: 'org.gnome.mutter' });
     },
 
+    blockUpdates: function() {
+        this._pauseWorkspaceCheck = true;
+    },
+
+    unblockUpdates: function() {
+        this._pauseWorkspaceCheck = false;
+    },
+
     _checkWorkspaces: function() {
         let i;
         let emptyWorkspaces = [];
@@ -229,6 +239,10 @@ const WorkspaceTracker = new Lang.Class({
             return false;
         }
 
+        // Update workspaces only if Dynamic Workspace Management has not been paused by some other function
+        if (this._pauseWorkspaceCheck)
+            return true;
+
         for (i = 0; i < this._workspaces.length; i++) {
             let lastRemoved = this._workspaces[i]._lastRemovedWindow;
             if ((lastRemoved &&
@@ -627,6 +641,8 @@ const WindowManager = new Lang.Class({
 
         this._allowedKeybindings = {};
 
+        this._isWorkspacePrepended = false;
+
         this._switchData = null;
         this._shellwm.connect('kill-switch-workspace', Lang.bind(this, this._switchWorkspaceDone));
         this._shellwm.connect('kill-window-effects', Lang.bind(this, function (shellwm, actor) {
@@ -915,6 +931,8 @@ const WindowManager = new Lang.Class({
         if (!Meta.prefs_get_dynamic_workspaces())
             return;
 
+        global.screen.append_new_workspace(false, global.get_current_time());
+
         let windows = global.get_window_actors().map(function(winActor) {
             return winActor.meta_window;
         });
@@ -1642,8 +1660,10 @@ const WindowManager = new Lang.Class({
         } else if (isNaN(target)) {
             // Prepend a new workspace dynamically
             if (screen.get_active_workspace_index() == 0 &&
-                action == 'move' && target == 'up')
+                action == 'move' && target == 'up' && this._isWorkspacePrepended == false) {
                 this.insertWorkspace(0);
+                this._isWorkspacePrepended = true;
+            }
 
             direction = Meta.MotionDirection[target.toUpperCase()];
             newWs = screen.get_active_workspace().get_neighbor(direction);
@@ -1668,9 +1688,12 @@ const WindowManager = new Lang.Class({
 
         if (!Main.overview.visible) {
             if (this._workspaceSwitcherPopup == null) {
+                this._workspaceTracker.blockUpdates();
                 this._workspaceSwitcherPopup = new WorkspaceSwitcherPopup.WorkspaceSwitcherPopup();
                 this._workspaceSwitcherPopup.connect('destroy', Lang.bind(this, function() {
+                    this._workspaceTracker.unblockUpdates();
                     this._workspaceSwitcherPopup = null;
+                    this._isWorkspacePrepended = false;
                 }));
             }
             this._workspaceSwitcherPopup.display(direction, newWs.index());