[pitivi] elements: Fix Video transition selection

[Thibault Saunier <tsaunier src gnome org>]

commit f5fd56e096926332b3a616f8d43c24ea6ef83164
Author: Thibault Saunier <tsaunier gnome org>
Date:   Wed May 6 16:09:10 2015 +0200

    elements: Fix Video transition selection
    
    Selecting a video transition should lead to the transition
    tab selection to be selected in the clip property pan.
    
    Rework a bit how we detect a transition is being selected,
    relying on the Selected object to emit "selecting-changed"
    instead if the GtkWidget flags.
    
    Also make audio only transitions insensitive.
    
    FIXES: http://phabricator.freedesktop.org/T53

 pitivi/timeline/elements.py |   39 ++++++++++++++++++---------------------
 pitivi/transitions.py       |    2 +-
 2 files changed, 19 insertions(+), 22 deletions(-)
---
diff --git a/pitivi/timeline/elements.py b/pitivi/timeline/elements.py
index f1da320..6192027 100644
--- a/pitivi/timeline/elements.py
+++ b/pitivi/timeline/elements.py
@@ -813,7 +813,7 @@ class TitleClip(SourceClip):
     __gtype_name__ = "PitiviTitleClip"
 
     def _childAdded(self, clip, child):
-        super(Title, self)._childAdded(clip, child)
+        super(TitleClip, self)._childAdded(clip, child)
 
         if isinstance(child, GES.Source):
             if child.get_track_type() == GES.TrackType.VIDEO:
@@ -828,16 +828,19 @@ class TransitionClip(Clip):
     __gtype_name__ = "PitiviTransitionClip"
 
     def __init__(self, layer, bClip):
+        self.__has_video = False
+
         super(TransitionClip, self).__init__(layer, bClip)
+
+        if self.__has_video:
+            self.z_order = 1
+        else:
+            self.z_order = 0
+            self.set_sensitive(False)
+
         self.get_style_context().add_class("TransitionClip")
-        self.z_order = 0
 
-        for child in bClip.get_children(True):
-            child.selected = timelineUtils.Selected()
         self.bClip.connect("child-added", self._childAddedCb)
-        self.selected = False
-        self.connect("state-flags-changed", self._selectedChangedCb)
-        self.connect("button-press-event", self._pressEventCb)
 
         # In the case of TransitionClips, we are the only container
         self._elements_container = self
@@ -845,29 +848,23 @@ class TransitionClip(Clip):
                                 str(bClip.props.vtype.value_nick))
 
     def _childAdded(self, clip, child):
-        if isinstance(child, GES.VideoTransition):
-            self.z_order += 1
-
         super(TransitionClip, self)._childAdded(clip, child)
 
+        if isinstance(child, GES.VideoTransition):
+            self.__has_video = True
+            child.selected.connect("selected-changed", self._selectedChangedCb, child)
+
     def do_draw(self, cr):
         Clip.do_draw(self, cr)
 
-    def _selectedChangedCb(self, unused_widget, flags):
-        if not [c for c in self.bClip.get_children(True) if isinstance(c, GES.VideoTransition)]:
-            return
-
-        if flags & Gtk.StateFlags.SELECTED:
-            self.timeline.parent.app.gui.trans_list.activate(self.bClip)
+    def _selectedChangedCb(self, unused_child, selected, child):
+        if selected:
+            self.timeline.parent.app.gui.trans_list.activate(child)
             self.selected = True
-        elif self.selected:
+        else:
             self.selected = False
             self.timeline.parent.app.gui.trans_list.deactivate()
 
-    def _pressEventCb(self, unused_action, unused_widget):
-        selection = {self.bClip}
-        self.timeline.selection.setSelection(selection, timelineUtils.SELECT)
-        return True
 
 GES_TYPE_UI_TYPE = {
     GES.UriClip.__gtype__: UriClip,
diff --git a/pitivi/transitions.py b/pitivi/transitions.py
index ec4fe23..eb5a39a 100644
--- a/pitivi/transitions.py
+++ b/pitivi/transitions.py
@@ -288,7 +288,7 @@ class TransitionsListWidget(Gtk.Box, Loggable):
         self.element.connect("notify::border", self._borderChangedCb)
         self.element.connect("notify::invert", self._invertChangedCb)
         self.element.connect("notify::type", self._transitionTypeChangedCb)
-        transition_asset = element.get_asset()
+        transition_asset = element.get_parent().get_asset()
         if transition_asset.get_id() == "crossfade":
             self.props_widgets.set_sensitive(False)
         else: