not destroying the Live Mode window on logout

(part of #1940)

campcaster/src/products/gLiveSupport/src/LiveModeWindow.h

@@ -361,6 +361,18 @@ class LiveModeWindow : public GuiWindow
          */
         void
         refreshPlaylist(Ptr<Playlist>::Ref  playlist)           throw ();
+
+        /**
+         *  Report whether the window is non-empty.
+         *
+         *  @return true if there is at least one Playable item in the window.
+         */
+        bool
+        isNotEmpty(void)                                        throw ()
+        {
+            return (treeModel->children().size() != 0);
+        }
+
 };
 
 /* ================================================= external data structures */

campcaster/src/products/gLiveSupport/src/MasterPanelWindow.cxx

@@ -678,7 +678,7 @@ MasterPanelWindow :: showAnonymousUI(void)                          throw ()
         if (liveModeWindow->is_visible()) {
             liveModeWindow->hide();
         }
-        liveModeWindow.reset();
+        // the Live Mode window is not destroyed at logout, unlike the others
     }
     if (uploadFileWindow.get()) {
         if (uploadFileWindow->is_visible()) {
@@ -755,6 +755,10 @@ MasterPanelWindow :: showLoggedInUI(void)                           throw ()
     }
     
     setSchedulerAvailable(gLiveSupport->isSchedulerAvailable());
+    
+    if (liveModeWindow && liveModeWindow->isNotEmpty()) {
+        liveModeWindow->present();
+    }
 }