Merge lp:~tombeckmann/gala/workspace-appears-focused-crash into lp:gala

[Tom Beckmann]

This solves the meta_window_appears_focused crashes happening during workspace switch by making sure a clone is destroied when its source is removed.

[Tom Beckmann (tombeckmann)]

Relevant bug: https://bugs.launchpad.net/gala/+bug/1119551

[lp:~tombeckmann/gala/workspace-appears-focused-crash]

309. By Tom Beckmann on 2013-03-23

Delete the clones list in watch_windows

310. By Tom Beckmann on 2013-03-23

Add info about the window if watch_window is called when it should not be called

311. By Tom Beckmann on 2013-03-23

Add a warning about the closed window

[Rico Tzschichholz (ricotz)]

review: Approve

=== modified file 'src/Plugin.vala'
--- src/Plugin.vala	2013-03-20 16:04:50 +0000
+++ src/Plugin.vala	2013-03-23 15:25:23 +0000
@@ -665,6 +665,25 @@
 		Clutter.Actor? out_group;
 		Clutter.Actor? moving_window_container;
 		
+		void watch_window (Meta.Workspace workspace, Meta.Window window)
+		{
+			if (clones == null) {
+				critical ("watch_window called on '%s' while not switching workspaces", window.get_title ());
+				return;
+			}
+
+			warning ("Dock window '%s' closed while switching workspaces", window.get_title ());
+			
+			// finding the correct window here is not so easy
+			// and for those default 400ms we can live with
+			// some windows disappearing which in fact should never
+			// happen unless a dock crashes
+			foreach (var clone in clones) {
+				clone.destroy ();
+			}
+			clones = null;
+		}
+		
 		public override void switch_workspace (int from, int to, MotionDirection direction)
 		{
 			if (!AnimationSettings.get_default ().enable_animations || AnimationSettings.get_default ().workspace_switch_duration == 0) {
@@ -744,6 +763,14 @@
 				}
 			}
 			
+			// monitor the workspaces to see whether a window was removed
+			// in which case we need to stop the clones from drawing
+			// we monitor every workspace here because finding the ones a
+			// particular dock belongs to did not seem reliable enough
+			foreach (var workspace in screen.get_workspaces ()) {
+				workspace.window_removed.connect (watch_window);
+			}
+			
 			in_group.set_position (-x2, -y2);
 			group.set_child_above_sibling (in_group, null);
 			if (moving_window_container != null)
@@ -784,10 +811,16 @@
 					clutter_actor_reparent (window, par.nth_data (i));
 			}
 			
-			clones.foreach ((clone) => {
-				clone.destroy ();
-			});
-			clones = null;
+			foreach (var workspace in screen.get_workspaces ()) {
+				workspace.window_removed.disconnect (watch_window);
+			}
+			
+			if (clones != null) {
+				foreach (var clone in clones) {
+					clone.destroy ();
+				}
+				clones = null;
+			}
 			
 			win = null;
 			par = null;