places: Implement drag&drop for overview

Add drag and drop.  We need to be able to recreate the icon texture,
so instead of passing it directly into PlaceDisplay, pass
a factory function which knows how to create a new texture.

js/ui/places.js

@@ -10,32 +10,61 @@ const Lang = imports.lang;
 const Mainloop = imports.mainloop;
 const Signals = imports.signals;
 
+const DND = imports.ui.dnd;
 const Main = imports.ui.main;
 const GenericDisplay = imports.ui.genericDisplay;
 
 const PLACES_VSPACING = 8;
 const PLACES_ICON_SIZE = 16;
 
-function PlaceDisplay(name, icon, onActivate) {
+/**
-    this._init(name, icon, onActivate);
+ * An entry in the places menu.
+ * @name: String title
+ * @iconFactory: A JavaScript callback which will create an icon texture
+ * @onActivate: A JavaScript callback to launch the entry
+ */
+function PlaceDisplay(name, iconFactory, onActivate) {
+    this._init(name, iconFactory, onActivate);
 }
 
 PlaceDisplay.prototype = {
-    _init : function(name, iconTexture, onActivate) {
+    _init : function(name, iconFactory, onActivate) {
         this.actor = new Big.Box({ orientation: Big.BoxOrientation.HORIZONTAL,
                                    reactive: true,
                                    spacing: 4 });
-        this.actor.connect('button-press-event', Lang.bind(this, function (b, e) {
+        this.actor.connect('button-release-event', Lang.bind(this, function (b, e) {
             onActivate(this);
+            Main.overview.hide();
         }));
         let text = new Clutter.Text({ font_name: "Sans 14px",
                                       ellipsize: Pango.EllipsizeMode.END,
                                       color: GenericDisplay.ITEM_DISPLAY_NAME_COLOR,
                                       text: name });
         let iconBox = new Big.Box({ y_align: Big.BoxAlignment.CENTER });
-        iconBox.append(iconTexture, Big.BoxPackFlags.NONE);
+        this._icon = iconFactory();
+        iconBox.append(this._icon, Big.BoxPackFlags.NONE);
         this.actor.append(iconBox, Big.BoxPackFlags.NONE);
         this.actor.append(text, Big.BoxPackFlags.EXPAND);
+
+        this._iconFactory = iconFactory;
+        this._onActivate = onActivate;
+
+        this.actor._delegate = this;
+        let draggable = DND.makeDraggable(this.actor);
+    },
+
+    getDragActorSource: function() {
+        return this._icon;
+    },
+
+    getDragActor: function(stageX, stageY) {
+        return this._iconFactory();
+    },
+
+    //// Drag and drop methods ////
+
+    shellWorkspaceLaunch : function() {
+        this._onActivate();
     }
 };
 Signals.addSignalMethods(PlaceDisplay.prototype);
@@ -59,11 +88,13 @@ Places.prototype = {
         let homeUri = homeFile.get_uri();
         let homeLabel = Shell.util_get_label_for_uri (homeUri);
         let homeIcon = Shell.util_get_icon_for_uri (homeUri);
-        let homeTexture = Shell.TextureCache.get_default().load_gicon(homeIcon, PLACES_ICON_SIZE);
+        let home = new PlaceDisplay(homeLabel,
-        let home = new PlaceDisplay(homeLabel, homeTexture, Lang.bind(this, function() {
+            function() {
-            Main.overview.hide();
+                return Shell.TextureCache.get_default().load_gicon(homeIcon, PLACES_ICON_SIZE);
+            },
+            function() {
                 Gio.app_info_launch_default_for_uri(homeUri, Main.createAppLaunchContext());
-        }));
+            });
 
         this._menuBox.append(home.actor, Big.BoxPackFlags.NONE);
 
@@ -79,19 +110,23 @@ Places.prototype = {
         }
 
         if (networkApp != null) {
-            let networkIcon = networkApp.create_icon_texture(PLACES_ICON_SIZE);
+            let network = new PlaceDisplay(networkApp.get_name(),
-            let network = new PlaceDisplay(networkApp.get_name(), networkIcon, Lang.bind(this, function () {
+                function() {
-                Main.overview.hide();
+                    return networkApp.create_icon_texture(PLACES_ICON_SIZE);
+                },
+                function () {
                     networkApp.launch();
-            }));
+                });
             this._menuBox.append(network.actor, Big.BoxPackFlags.NONE);
         }
 
-        let connectIcon = Shell.TextureCache.get_default().load_icon_name("applications-internet", PLACES_ICON_SIZE);
+        let connect = new PlaceDisplay('Connect to...',
-        let connect = new PlaceDisplay('Connect to...', connectIcon, Lang.bind(this, function () {
+            function () {
-            Main.overview.hide();
+                return Shell.TextureCache.get_default().load_icon_name("applications-internet", PLACES_ICON_SIZE);
+            },
+            function () {
                 new Shell.Process({ args: ['nautilus-connect-server'] }).run();
-        }));
+            });
         this._menuBox.append(connect.actor, Big.BoxPackFlags.NONE);
 
         this._bookmarksPath = GLib.build_filenamev([GLib.get_home_dir(), ".gtk-bookmarks"]);
@@ -149,11 +184,14 @@ Places.prototype = {
             if (label == null)
                 continue;
             let icon = Shell.util_get_icon_for_uri(bookmark);
-            let iconTexture = Shell.TextureCache.get_default().load_gicon(icon, PLACES_ICON_SIZE);
+
-            let item = new PlaceDisplay(label, iconTexture, Lang.bind(this, function() {
+            let item = new PlaceDisplay(label,
-                Main.overview.hide();
+                function() {
+                    return Shell.TextureCache.get_default().load_gicon(icon, PLACES_ICON_SIZE);
+                },
+                function() {
                     Gio.app_info_launch_default_for_uri(bookmark, Main.createAppLaunchContext());
-            }));
+                });
             this._dirsBox.append(item.actor, Big.BoxPackFlags.NONE);
         }
     }