[clutter] drag-action: Ensure that we can destroy the drag handle

[Emmanuele Bassi <ebassi src gnome org>]

commit 06ea2cf7b1d0a22985e3753e855b731cc52724a8
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Mon Aug 20 18:56:20 2012 +0100

    drag-action: Ensure that we can destroy the drag handle
    
    If the DragAction has a drag handle that gets destroyed inside the
    ::drag-end signal handler, the destruction sequence will trigger a
    callback we have in place to check if the handle is being destroyed
    mid-drag, e.g. from a ::drag-motion event.
    
    The callback on the drag handle destruction will check if we are still
    in the middle of a drag and emit the ::drag-end signal to allow cleaning
    up; the callback erroneously uses the drag handle as the argument for
    the emit_drag_end() function â instead of the actor to which the drag
    action has been attached. Also, by the time we emit the ::drag-end, we
    are not dragging the actor any more, so we shouldn't be emitted the
    ::drag-end signal twice.
    
    The fix is, thus, made of two parts:
    
      - reset the in_drag boolean before emitting the ::drag-end signal
        so that destroying the drag handle will not result in a double
        signal emission;
    
      - use the correct actor when calling emit_drag_end().
    
    https://bugzilla.gnome.org/show_bug.cgi?id=681814

 clutter/clutter-drag-action.c |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)
---
diff --git a/clutter/clutter-drag-action.c b/clutter/clutter-drag-action.c
index d686ef9..a58ec4d 100644
--- a/clutter/clutter-drag-action.c
+++ b/clutter/clutter-drag-action.c
@@ -306,6 +306,8 @@ emit_drag_end (ClutterDragAction *action,
       priv->last_motion_device = clutter_event_get_device (event);
     }
 
+  priv->in_drag = FALSE;
+
   /* we might not have emitted ::drag-begin yet */
   if (!priv->emit_delayed_press)
     g_signal_emit (action, drag_signals[DRAG_END], 0,
@@ -334,8 +336,6 @@ emit_drag_end (ClutterDragAction *action,
     }
 
   priv->sequence = NULL;
-
-  priv->in_drag = FALSE;
 }
 
 static gboolean
@@ -1062,12 +1062,14 @@ clutter_drag_action_get_drag_threshold (ClutterDragAction *action,
 }
 
 static void
-on_drag_handle_destroy (ClutterActor      *actor,
+on_drag_handle_destroy (ClutterActor      *handle,
                         ClutterDragAction *action)
 {
   ClutterDragActionPrivate *priv = action->priv;
+  ClutterActor *actor;
 
   /* make sure we reset the state */
+  actor = clutter_actor_meta_get_actor (CLUTTER_ACTOR_META (action));
   if (priv->in_drag)
     emit_drag_end (action, actor, NULL);