[gnome-shell] overviewControls: fade view selector and thumbnails slider on DnD

[Cosimo Cecchi <cosimoc src gnome org>]

commit 1db6d15677221ee05050b32bd2802c8cfad68023
Author: Cosimo Cecchi <cosimoc gnome org>
Date:   Sun Feb 17 23:45:24 2013 -0500

    overviewControls: fade view selector and thumbnails slider on DnD
    
    When an item is dragged from a page that is not the windows one, the
    only possible target is the dash, so fade out the rest.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=686984

 js/ui/overviewControls.js |   15 +++++++++++++++
 js/ui/viewSelector.js     |   16 ++++++++++++++++
 2 files changed, 31 insertions(+), 0 deletions(-)
---
diff --git a/js/ui/overviewControls.js b/js/ui/overviewControls.js
index ccd6543..e03b572 100644
--- a/js/ui/overviewControls.js
+++ b/js/ui/overviewControls.js
@@ -341,6 +341,21 @@ const ControlsManager = new Lang.Class({
         this._viewSelector = viewSelector;
         this._viewSelector.connect('page-changed', Lang.bind(this, this._setVisibility));
         this._viewSelector.connect('page-empty', Lang.bind(this, this._onPageEmpty));
+
+        Main.overview.connect('item-drag-begin', Lang.bind(this,
+            function() {
+                let activePage = this._viewSelector.getActivePage();
+                if (activePage != ViewSelector.ViewPage.WINDOWS)
+                    this._viewSelector.fadeHalf();
+            }));
+        Main.overview.connect('item-drag-end', Lang.bind(this,
+            function() {
+                this._viewSelector.fadeIn();
+            }));
+        Main.overview.connect('item-drag-cancelled', Lang.bind(this,
+            function() {
+                this._viewSelector.fadeIn();
+            }));
     },
 
     _setVisibility: function() {
diff --git a/js/ui/viewSelector.js b/js/ui/viewSelector.js
index 4e1f1df..386150f 100644
--- a/js/ui/viewSelector.js
+++ b/js/ui/viewSelector.js
@@ -502,6 +502,22 @@ const ViewSelector = new Lang.Class({
             return ViewPage.APPS;
         else
             return ViewPage.SEARCH;
+    },
+
+    fadeIn: function() {
+        let actor = this._activePage;
+        Tweener.addTween(actor, { opacity: 255,
+                                  time: OverviewControls.SIDE_CONTROLS_ANIMATION_TIME / 2,
+                                  transition: 'easeInQuad'
+                                });
+    },
+
+    fadeHalf: function() {
+        let actor = this._activePage;
+        Tweener.addTween(actor, { opacity: 128,
+                                  time: OverviewControls.SIDE_CONTROLS_ANIMATION_TIME / 2,
+                                  transition: 'easeOutQuad'
+                                });
     }
 });
 Signals.addSignalMethods(ViewSelector.prototype);