[gnome-shell] workspaceThumbnail: unify restack handling

[Cosimo Cecchi <cosimoc src gnome org>]

commit 6c64c0873c64fe233f5bdffb6622cff9f4f689bf
Author: Cosimo Cecchi <cosimoc gnome org>
Date:   Thu Dec 13 11:00:30 2012 -0500

    workspaceThumbnail: unify restack handling
    
    Both WorkspacesDisplay and ThumbnailsBox need to know when windows have been
    restacked. Instead of each tracking changes on their own or trying to call
    each other, have the overview keep track and do the calculations, emitting
    a signal with the result.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=690175

 js/ui/overview.js           |   14 ++++++++++++++
 js/ui/workspaceThumbnail.js |   10 +++++++++-
 js/ui/workspacesView.js     |   18 +++---------------
 3 files changed, 26 insertions(+), 16 deletions(-)
---
diff --git a/js/ui/overview.js b/js/ui/overview.js
index 5bb8fa1..84cd48c 100644
--- a/js/ui/overview.js
+++ b/js/ui/overview.js
@@ -174,6 +174,8 @@ const Overview = new Lang.Class({
         Main.xdndHandler.connect('drag-begin', Lang.bind(this, this._onDragBegin));
         Main.xdndHandler.connect('drag-end', Lang.bind(this, this._onDragEnd));
 
+        global.screen.connect('restacked', Lang.bind(this, this._onRestacked));
+
         this._windowSwitchTimeoutId = 0;
         this._windowSwitchTimestamp = 0;
         this._lastActiveWorkspaceIndex = -1;
@@ -383,6 +385,18 @@ const Overview = new Lang.Class({
         this._coverPane.set_size(primary.width, contentHeight);
     },
 
+    _onRestacked: function() {
+        let stack = global.get_window_actors();
+        let stackIndices = {};
+
+        for (let i = 0; i < stack.length; i++) {
+            // Use the stable sequence for an integer to use as a hash key
+            stackIndices[stack[i].get_meta_window().get_stable_sequence()] = i;
+        }
+
+        this.emit('windows-restacked', stackIndices);
+    },
+
     //// Public methods ////
 
     beginItemDrag: function(source) {
diff --git a/js/ui/workspaceThumbnail.js b/js/ui/workspaceThumbnail.js
index b381dab..fd68ce5 100644
--- a/js/ui/workspaceThumbnail.js
+++ b/js/ui/workspaceThumbnail.js
@@ -745,6 +745,9 @@ const ThumbnailsBox = new Lang.Class({
         this._nWorkspacesNotifyId =
             global.screen.connect('notify::n-workspaces',
                                   Lang.bind(this, this._workspacesChanged));
+        this._syncStackingId =
+            Main.overview.connect('windows-restacked',
+                                  Lang.bind(this, this._syncStacking));
 
         this._targetScale = 0;
         this._scale = 0;
@@ -780,6 +783,11 @@ const ThumbnailsBox = new Lang.Class({
             this._nWorkspacesNotifyId = 0;
         }
 
+        if (this._syncStackingId > 0) {
+            Main.overview.disconnect(this._syncStackingId);
+            this._syncStackingId = 0;
+        }
+
         for (let w = 0; w < this._thumbnails.length; w++)
             this._thumbnails[w].destroy();
         this._thumbnails = [];
@@ -854,7 +862,7 @@ const ThumbnailsBox = new Lang.Class({
         this._queueUpdateStates();
     },
 
-    syncStacking: function(stackIndices) {
+    _syncStacking: function(overview, stackIndices) {
         for (let i = 0; i < this._thumbnails.length; i++)
             this._thumbnails[i].syncStacking(stackIndices);
     },
diff --git a/js/ui/workspacesView.js b/js/ui/workspacesView.js
index 5e66c21..4d22f35 100644
--- a/js/ui/workspacesView.js
+++ b/js/ui/workspacesView.js
@@ -577,7 +577,7 @@ const WorkspacesDisplay = new Lang.Class({
         this._updateWorkspacesViews();
 
         this._restackedNotifyId =
-            global.screen.connect('restacked',
+            Main.overview.connect('windows-restacked',
                                   Lang.bind(this, this._onRestacked));
 
         if (this._itemDragBeginId == 0)
@@ -598,8 +598,6 @@ const WorkspacesDisplay = new Lang.Class({
         if (this._windowDragEndId == 0)
             this._windowDragEndId = Main.overview.connect('window-drag-end',
                                                           Lang.bind(this, this._dragEnd));
-
-        this._onRestacked();
     },
 
     zoomFromOverview: function() {
@@ -615,7 +613,7 @@ const WorkspacesDisplay = new Lang.Class({
             this.zoomFraction = 0;
 
         if (this._restackedNotifyId > 0){
-            global.screen.disconnect(this._restackedNotifyId);
+            Main.overview.disconnect(this._restackedNotifyId);
             this._restackedNotifyId = 0;
         }
         if (this._itemDragBeginId > 0) {
@@ -877,19 +875,9 @@ const WorkspacesDisplay = new Lang.Class({
         }
     },
 
-    _onRestacked: function() {
-        let stack = global.get_window_actors();
-        let stackIndices = {};
-
-        for (let i = 0; i < stack.length; i++) {
-            // Use the stable sequence for an integer to use as a hash key
-            stackIndices[stack[i].get_meta_window().get_stable_sequence()] = i;
-        }
-
+    _onRestacked: function(overview, stackIndices) {
         for (let i = 0; i < this._workspacesViews.length; i++)
             this._workspacesViews[i].syncStacking(stackIndices);
-
-        this._thumbnailsBox.syncStacking(stackIndices);
     },
 
     _workspacesChanged: function() {