[pitivi] Fix crash when trying to configure an effect which as not readable properties

[Edward Hervey <edwardrv src gnome org>]

commit 5fb4da99ce4c2e161e008323f8f44275303deb17
Author: Thibault Saunier <tsaunier gnome org>
Date:   Fri Sep 3 20:40:33 2010 +0200

    Fix crash when trying to configure an effect which as not readable properties

 pitivi/effects.py                 |    3 ++-
 pitivi/formatters/etree.py        |   11 ++++++-----
 pitivi/ui/effectsconfiguration.py |    3 ++-
 pitivi/ui/gstwidget.py            |    4 ++++
 4 files changed, 14 insertions(+), 7 deletions(-)
---
diff --git a/pitivi/effects.py b/pitivi/effects.py
index 6a04d3a..d8c4c3e 100644
--- a/pitivi/effects.py
+++ b/pitivi/effects.py
@@ -332,7 +332,8 @@ class EffectGstElementPropertyChangeTracker:
             gst_element.connect('notify::' + prop.name,
                                 self._propertyChangedCb,
                                 gst_element)
-            properties[prop.name] = gst_element.get_property(prop.name)
+            if prop.flags & gobject.PARAM_READABLE:
+                properties[prop.name] = gst_element.get_property(prop.name)
         self._tracked_effects[gst_element] = properties
 
     def _propertyChangedCb(self, gst_element, pspec, unused):
diff --git a/pitivi/formatters/etree.py b/pitivi/formatters/etree.py
index f9fbbf5..eabc377 100644
--- a/pitivi/formatters/etree.py
+++ b/pitivi/formatters/etree.py
@@ -360,11 +360,12 @@ class ElementTreeFormatter(Formatter):
         for prop in properties:
             type_name = str(gobject.type_name(prop.value_type.fundamental))
             #FIXME we just take the int equivalent to the GEnum, how should it be handled?
-            if type_name == "GEnum":
-                value = str(effect.get_property(prop.name).__int__())
-            else:
-                value = str(effect.get_property(prop.name))
-            effect_properties.attrib[prop.name] = '(' + type_name + ')' + value
+            if prop.flags & gobject.PARAM_READABLE:
+                if type_name == "GEnum":
+                    value = str(effect.get_property(prop.name).__int__())
+                else:
+                    value = str(effect.get_property(prop.name))
+                effect_properties.attrib[prop.name] = '(' + type_name + ')' + value
         effect_element.append(effect_properties)
 
 
diff --git a/pitivi/ui/effectsconfiguration.py b/pitivi/ui/effectsconfiguration.py
index 3e48940..1d7628a 100644
--- a/pitivi/ui/effectsconfiguration.py
+++ b/pitivi/ui/effectsconfiguration.py
@@ -65,7 +65,8 @@ class EffectsPropertiesHandling:
         self._current_effect_setting_ui = effect_set_ui
         element = self._current_effect_setting_ui.element
         for prop in gobject.list_properties(element):
-            self._current_element_values[prop.name] = element.get_property(prop.name)
+            if prop.flags & gobject.PARAM_READABLE:
+                self._current_element_values[prop.name] = element.get_property(prop.name)
 
         return self.cache_dict[effect]
 
diff --git a/pitivi/ui/gstwidget.py b/pitivi/ui/gstwidget.py
index d4ee244..1aa6880 100644
--- a/pitivi/ui/gstwidget.py
+++ b/pitivi/ui/gstwidget.py
@@ -111,6 +111,10 @@ class GstElementSettingsWidget(gtk.VBox, Loggable):
         table.set_border_width(5)
         y = 0
         for prop in props:
+            if not prop.flags & gobject.PARAM_WRITABLE\
+              or not prop.flags & gobject.PARAM_READABLE:
+                continue
+
             label = gtk.Label(prop.nick+":")
             label.set_alignment(0.0, 0.5)
             table.attach(label, 0, 1, y, y+1, xoptions=gtk.FILL, yoptions=gtk.FILL)