AppMenuButton: Improve handling of signals

If for some reason an extension needs to destroy the AppMenu object,
currently it is not possible to do this cleanly due to these signals
remaining connected.

https://bugzilla.gnome.org/show_bug.cgi?id=698531

diff --git a/js/ui/panel.js b/js/ui/panel.js
index 5d2952cf77f486e53b55e912cf2cd4b21dcbfbc4..332be12b137b9c0b8156d7d62d60c37ebea74676 100644 (file)
--- a/js/ui/panel.js
+++ b/js/ui/panel.js
@@ -289,10 +289,10 @@ const AppMenuButton = new Lang.Class({
         this._visible = !Main.overview.visible;
         if (!this._visible)
             this.actor.hide();
-        Main.overview.connect('hiding', Lang.bind(this, function () {
+        this._overviewHidingId = Main.overview.connect('hiding', Lang.bind(this, function () {
             this.show();
         }));
-        Main.overview.connect('showing', Lang.bind(this, function () {
+        this._overviewShowingId = Main.overview.connect('showing', Lang.bind(this, function () {
             this.hide();
         }));
 
@@ -302,10 +302,12 @@ const AppMenuButton = new Lang.Class({
 
         let tracker = Shell.WindowTracker.get_default();
         let appSys = Shell.AppSystem.get_default();
-        tracker.connect('notify::focus-app', Lang.bind(this, this._focusAppChanged));
-        appSys.connect('app-state-changed', Lang.bind(this, this._onAppStateChanged));
-
-        global.window_manager.connect('switch-workspace', Lang.bind(this, this._sync));
+        this._focusAppNotifyId =
+            tracker.connect('notify::focus-app', Lang.bind(this, this._focusAppChanged));
+        this._appStateChangedSignalId =
+            appSys.connect('app-state-changed', Lang.bind(this, this._onAppStateChanged));
+        this._switchWorkspaceNotifyId =
+            global.window_manager.connect('switch-workspace', Lang.bind(this, this._sync));
 
         this._sync();
     },
@@ -643,6 +645,33 @@ const AppMenuButton = new Lang.Class({
 
         this.setMenu(menu);
         this._menuManager.addMenu(menu);
+    },
+
+    destroy: function() {
+        if (this._appStateChangedSignalId > 0) {
+            let appSys = Shell.AppSystem.get_default();
+            appSys.disconnect(this._appStateChangedSignalId);
+            this._appStateChangedSignalId = 0;
+        }
+        if (this._focusAppNotifyId > 0) {
+            let tracker = Shell.WindowTracker.get_default();
+            tracker.disconnect(this._focusAppNotifyId);
+            this._focusAppNotifyId = 0;
+        }
+        if (this._overviewHidingId > 0) {
+            Main.overview.disconnect(this._overviewHidingId);
+            this._overviewHidingId = 0;
+        }
+        if (this._overviewShowingId > 0) {
+            Main.overview.disconnect(this._overviewShowingId);
+            this._overviewShowingId = 0;
+        }
+        if (this._switchWorkspaceNotifyId > 0) {
+            global.window_manager.disconnect(this._switchWorkspaceNotifyId);
+            this._switchWorkspaceNotifyId = 0;
+        }
+
+        this.parent();
     }
 });