[glade/gbinding] Deal with binding sourc properties becoming disabled or insensitive

[Denis Washington <denisw src gnome org>]

commit d147a97285440dd6f25a977792e70640bd0dd8bf
Author: Denis Washington <denisw src gnome org>
Date:   Sun Aug 7 18:02:14 2011 +0200

    Deal with binding sourc properties becoming disabled or insensitive
    
    Now, when the binding source of a property is disabled, the property
    is reset to its default value and unbound. Enabling the source again
    rebinds the property. Such "dead" property bindings are not saved
    and thus only persist as long as Glade is opened. I hope this behavior
    is in line in what users would expect; if not, it's easy to change.

 gladeui/glade-property.c |   67 +++++++++++++++++++++++++++++++++++++--------
 1 files changed, 55 insertions(+), 12 deletions(-)
---
diff --git a/gladeui/glade-property.c b/gladeui/glade-property.c
index 860f62f..76606ce 100644
--- a/gladeui/glade-property.c
+++ b/gladeui/glade-property.c
@@ -108,12 +108,10 @@ struct _GladePropertyPrivate {
                                         * GladeProperty's value is bound to
                                         */
 
-  gboolean            binding_source_valid;  /* TRUE if the property's binding source is
-                                              * valid, that is, if the binding source widget
-                                              * is part of the project (we cannot just
-                                              * set binding_source to NULL if the source widget
-                                              * is removed as we want to support undo)
-                                              */
+  /* Binding source validility flags */
+  gboolean            binding_source_alive;
+  gboolean            binding_source_enabled;
+  gboolean            binding_source_sensitive;
 
   gchar              *binding_transform_func;  /* the transformation function for
                                                 * the property's binding
@@ -124,6 +122,16 @@ struct _GladePropertyPrivate {
                                          * source (if it is bound)
                                          */
 
+  gulong              binding_enabled_handler;  /* Signal handler to keeep
+                                                 * binding_source_enabled
+                                                 * updated
+                                                 */
+
+  gulong              binding_sensitive_handler;  /* Signal handler to keeep
+                                                   * binding_source_sensitive
+                                                   * updated
+                                                   */
+
   gulong              binding_widget_remove_handler;  /* Signal handler to update
                                                        * binding_source_valid when the
                                                        * binding source widget is removed
@@ -648,9 +656,10 @@ glade_property_init (GladeProperty * property)
   property->priv->enabled = TRUE;
   property->priv->sensitive = TRUE;
   property->priv->binding_source = NULL;
-  property->priv->binding_source_valid = TRUE;  
   property->priv->binding_transform_func = NULL;
   property->priv->binding_handler = 0;
+  property->priv->binding_enabled_handler = 0;
+  property->priv->binding_sensitive_handler = 0;
   property->priv->binding_widget_remove_handler = 0;
   property->priv->binding_widget_add_handler = 0;  
   property->priv->i18n_translatable = TRUE;
@@ -1754,7 +1763,9 @@ glade_property_get_binding_source (GladeProperty *property)
 {
   g_return_val_if_fail (GLADE_IS_PROPERTY (property), NULL);
 
-  if (property->priv->binding_source_valid)
+  if (property->priv->binding_source_alive &&
+      property->priv->binding_source_enabled &&
+      property->priv->binding_source_sensitive)
     return property->priv->binding_source;
   else
     return NULL;
@@ -1778,7 +1789,7 @@ glade_property_binding_source_widget_cb (GladeProject *project,
 
   if (widget == glade_property_get_widget (priv->binding_source))
     {
-      priv->binding_source_valid = !priv->binding_source_valid;
+      priv->binding_source_alive = !priv->binding_source_alive;
       g_object_notify_by_pspec (G_OBJECT (property),
                                 properties[PROP_BINDING_SOURCE]);
     }
@@ -1798,6 +1809,10 @@ glade_property_remove_binding_source (GladeProperty *property)
 
   if (property->priv->binding_handler > 0)
     g_signal_handler_disconnect (old_source, property->priv->binding_handler);
+  if (property->priv->binding_enabled_handler > 0)
+    g_signal_handler_disconnect (old_source, property->priv->binding_enabled_handler);
+  if (property->priv->binding_sensitive_handler > 0)
+    g_signal_handler_disconnect (old_source, property->priv->binding_sensitive_handler);
 
   /* The property's widget might be currently finalized and have
    * its project set to NULL, so prefer to query the binding source
@@ -1830,6 +1845,16 @@ glade_property_remove_binding_source (GladeProperty *property)
 }
 
 static void
+glade_property_binding_source_valid_notify_cb (GladeProperty *source,
+                                               GParamSpec    *pspec,
+                                               GladeProperty *property)
+{
+  /* Rebind if the source property's "enabled" or
+     "sensitive" state changes */
+  glade_property_set_binding_source (property, source);
+}
+
+static void
 glade_property_binding_source_value_changed_cb (GladeProperty *prop,
                                                 GValue        *old_value,
                                                 GValue        *new_value,
@@ -1862,6 +1887,16 @@ glade_property_set_binding_source (GladeProperty *property,
                          (GWeakNotify) glade_property_binding_source_weak_notify_cb,
                          property);
 
+      property->priv->binding_enabled_handler =
+        g_signal_connect (binding_source, "notify::enabled",
+                          G_CALLBACK (glade_property_binding_source_valid_notify_cb),
+                          property);
+
+      property->priv->binding_sensitive_handler =
+        g_signal_connect (binding_source, "notify::sensitive",
+                          G_CALLBACK (glade_property_binding_source_valid_notify_cb),
+                          property);
+
       /* To be called when the binding source widget is deleted */
       closure =
         g_cclosure_new (G_CALLBACK (glade_property_binding_source_widget_cb),
@@ -1879,14 +1914,18 @@ glade_property_set_binding_source (GladeProperty *property,
       property->priv->binding_widget_add_handler =
         g_signal_connect_closure (project, "add-widget", closure, FALSE);
 
-      property->priv->binding_source_valid = TRUE;
+      property->priv->binding_source_alive = TRUE;
+      property->priv->binding_source_enabled = glade_property_get_enabled (binding_source);
+      property->priv->binding_source_sensitive = glade_property_get_sensitive (binding_source);
 
       /* Synchronize the source and target property values if there
        * is no transformation function; if there is, the best thing we
        * can do is to reset the target property to the default value
        * (the source and target property types might not be compatible)
        */
-      if (glade_property_get_binding_transform_func (property))
+      if (glade_property_get_binding_transform_func (property) ||
+          !property->priv->binding_source_enabled ||
+          !property->priv->binding_source_sensitive)
         glade_property_reset (property);
       else
         {
@@ -1902,6 +1941,8 @@ glade_property_set_binding_source (GladeProperty *property,
   else
     {
       property->priv->binding_handler = 0;
+      property->priv->binding_enabled_handler = 0;
+      property->priv->binding_sensitive_handler = 0;
       property->priv->binding_widget_remove_handler = 0;
       property->priv->binding_widget_add_handler = 0;
     }
@@ -1916,7 +1957,9 @@ glade_property_get_binding_transform_func (GladeProperty *property)
 {
   g_return_val_if_fail (GLADE_IS_PROPERTY (property), NULL);
 
-  if (property->priv->binding_source_valid)
+  if (property->priv->binding_source_alive &&
+      property->priv->binding_source_enabled &&
+      property->priv->binding_source_sensitive)
     return property->priv->binding_transform_func;
   else
     return NULL;