[gnome-boxes] Enable key navigation

[Alexander Larsson <alexl src gnome org>]

commit cb2467845972328302dc004c12b424f9542537a6
Author: Alexander Larsson <alexl redhat com>
Date:   Thu Sep 27 19:50:25 2012 +0200

    Enable key navigation
    
    We derive from GtkClutterEmbed and remove focusability and key event
    handling. This means that to Gtk+ it looks like a dumb container
    which never gets any key events. This makes Gtk+ keynav work just
    like in any other container, although it means there will never
    be any Clutter key events. Thats fine though, as we just use
    Clutter as a rendering layer.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=684988

 src/Makefile.am         |    1 +
 src/app.vala            |    4 ++--
 src/clutter-widget.vala |   25 +++++++++++++++++++++++++
 3 files changed, 28 insertions(+), 2 deletions(-)
---
diff --git a/src/Makefile.am b/src/Makefile.am
index 46ee57e..d61310c 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -77,6 +77,7 @@ EXTRA_DIST += $(libcommon_a_DEPENDENCIES) $(libcommon_a_VALASOURCES)
 bin_PROGRAMS = gnome-boxes
 
 gnome_boxes_SOURCES =				\
+	clutter-widget.vala			\
 	app.vala				\
 	collection-view.vala			\
 	collection.vala				\
diff --git a/src/app.vala b/src/app.vala
index 7c58d0c..6324f39 100644
--- a/src/app.vala
+++ b/src/app.vala
@@ -23,7 +23,7 @@ private class Boxes.App: Boxes.UI {
     }
     private bool maximized { get { return WindowState.MAXIMIZED in window.get_window ().get_state (); } }
     public Gtk.Notebook notebook;
-    public GtkClutter.Embed embed;
+    public ClutterWidget embed;
     public Clutter.Stage stage;
     public Clutter.BinLayout stage_bin;
     public Clutter.Actor overlay_bin_actor;
@@ -407,7 +407,7 @@ private class Boxes.App: Boxes.UI {
         notebook.show_border = false;
         notebook.show_tabs = false;
         window.add (notebook);
-        embed = new GtkClutter.Embed ();
+        embed = new ClutterWidget ();
         notebook.append_page (embed, null);
 
         display_page = new DisplayPage ();
diff --git a/src/clutter-widget.vala b/src/clutter-widget.vala
new file mode 100644
index 0000000..5404cab
--- /dev/null
+++ b/src/clutter-widget.vala
@@ -0,0 +1,25 @@
+// This file is part of GNOME Boxes. License: LGPLv2+
+using Gtk;
+using Clutter;
+
+/* We overide all keyboard handling of GtkClutter.Embed, as it interfers
+   with the key event propagation and thus focus navigation in gtk+.
+   We also make the embed itself non-focusable, as we want to treat it
+   like a container of Gtk+ widget rather than an edge widget which gets
+   keyboard events.
+   This means we will never get any Clutter key events, but that is
+   fine, as all our keyboard input is into GtkClutterActors, and clutter
+   is just used as a nice way of animating and rendering Gtk+ widgets
+   and some non-active graphical things.
+*/
+private class Boxes.ClutterWidget: GtkClutter.Embed {
+    public ClutterWidget () {
+		set_can_focus (false);
+    }
+	public override bool key_press_event (Gdk.EventKey event) {
+		return false;
+	}
+	public override bool key_release_event (Gdk.EventKey event) {
+		return false;
+	}
+}