[gtk+] gtkplacesview: don't rely on widgets on headers

[Carlos Soriano Sánchez <csoriano src gnome org>]

commit 03cd8e95584e64b28e56fa2ea4bc7f27c786deed
Author: Carlos Soriano <csoriano gnome org>
Date:   Sat Aug 29 20:36:48 2015 +0200

    gtkplacesview: don't rely on widgets on headers
    
    We are showing a GtkSpinner on the networks header to provide feedback
    to the user if we are fetching networks, therefore we have to modify
    the spinner state when doing it.
    However GtkListBox doesn't give guarantees about the widgets
    set by gtk_list_box_set_header, and we could access an invalid
    widget.
    
    To avoid to access invalid widgets, bind the fetching networks
    view property to the networks header spinner active property instead
    of modifying directly the spinner in the private structure.
    
    Not having the spinner in the private structure also makes the code
    cleaner.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=754150

 gtk/gtkplacesview.c |   72 +++++++++++++++++++++++++++++++++++++++++---------
 1 files changed, 59 insertions(+), 13 deletions(-)
---
diff --git a/gtk/gtkplacesview.c b/gtk/gtkplacesview.c
index 15acceb..9c34ffb 100644
--- a/gtk/gtkplacesview.c
+++ b/gtk/gtkplacesview.c
@@ -69,7 +69,6 @@ struct _GtkPlacesViewPrivate
   GtkWidget                     *recent_servers_popover;
   GtkWidget                     *recent_servers_stack;
   GtkWidget                     *stack;
-  GtkWidget                     *network_header_spinner;
   GtkWidget                     *network_placeholder;
   GtkWidget                     *network_placeholder_label;
 
@@ -100,6 +99,11 @@ static gboolean    on_row_popup_menu                             (GtkPlacesViewR
 
 static void        populate_servers                              (GtkPlacesView *view);
 
+static gboolean    gtk_places_view_get_fetching_networks         (GtkPlacesView *view);
+
+static void        gtk_places_view_set_fetching_networks         (GtkPlacesView *view,
+                                                                  gboolean       fetching_networks);
+
 G_DEFINE_TYPE_WITH_PRIVATE (GtkPlacesView, gtk_places_view, GTK_TYPE_BOX)
 
 /* GtkPlacesView properties & signals */
@@ -107,6 +111,7 @@ enum {
   PROP_0,
   PROP_LOCAL_ONLY,
   PROP_OPEN_FLAGS,
+  PROP_FETCHING_NETWORKS,
   PROP_LOADING,
   LAST_PROP
 };
@@ -416,6 +421,10 @@ gtk_places_view_get_property (GObject    *object,
       g_value_set_boolean (value, gtk_places_view_get_loading (self));
       break;
 
+    case PROP_FETCHING_NETWORKS:
+      g_value_set_boolean (value, gtk_places_view_get_fetching_networks (self));
+      break;
+
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
     }
@@ -876,9 +885,8 @@ update_network_state (GtkPlacesView *view)
       gtk_list_box_invalidate_headers (GTK_LIST_BOX (priv->listbox));
     }
 
-  if (priv->fetching_networks)
+  if (gtk_places_view_get_fetching_networks (view))
     {
-      gtk_spinner_start (GTK_SPINNER (priv->network_header_spinner));
       /* only show a placeholder with a message if the list is empty.
        * otherwise just show the spinner in the header */
       if (!has_networks (view))
@@ -890,14 +898,12 @@ update_network_state (GtkPlacesView *view)
     }
   else if (!has_networks (view))
     {
-      gtk_spinner_stop (GTK_SPINNER (priv->network_header_spinner));
       gtk_widget_show_all (priv->network_placeholder);
       gtk_label_set_text (GTK_LABEL (priv->network_placeholder_label),
                           _("No network locations found"));
     }
   else
     {
-      gtk_spinner_stop (GTK_SPINNER (priv->network_header_spinner));
       gtk_widget_hide (priv->network_placeholder);
     }
 }
@@ -950,7 +956,7 @@ network_enumeration_next_files_finished (GObject      *source_object,
   priv = gtk_places_view_get_instance_private (view);
   error = NULL;
 
-  priv->fetching_networks = FALSE;
+  gtk_places_view_set_fetching_networks (view, FALSE);
   detected_networks = g_file_enumerator_next_files_finish (G_FILE_ENUMERATOR (source_object),
                                                            res, &error);
 
@@ -1021,7 +1027,7 @@ fetch_networks (GtkPlacesView *view)
   g_cancellable_cancel (priv->networks_fetching_cancellable);
   g_clear_object (&priv->networks_fetching_cancellable);
   priv->networks_fetching_cancellable = g_cancellable_new ();
-  priv->fetching_networks = TRUE;
+  gtk_places_view_set_fetching_networks (view, TRUE);
   update_network_state (view);
 
   g_file_enumerate_children_async (network_file,
@@ -1053,7 +1059,6 @@ update_places (GtkPlacesView *view)
   children = gtk_container_get_children (GTK_CONTAINER (priv->listbox));
   g_list_free_full (children, (GDestroyNotify) gtk_widget_destroy);
   priv->network_placeholder = NULL;
-  priv->network_header_spinner = NULL;
 
   priv->loading = TRUE;
   g_object_notify_by_pspec (G_OBJECT (view), properties[PROP_LOADING]);
@@ -1931,11 +1936,9 @@ listbox_header_func (GtkListBoxRow *row,
                      GtkListBoxRow *before,
                      gpointer       user_data)
 {
-  GtkPlacesViewPrivate *priv;
   gboolean row_is_network;
   gchar *text;
 
-  priv = gtk_places_view_get_instance_private (GTK_PLACES_VIEW (user_data));
   text = NULL;
   row_is_network = GPOINTER_TO_INT (g_object_get_data (G_OBJECT (row), "is-network"));
 
@@ -1973,18 +1976,25 @@ listbox_header_func (GtkListBoxRow *row,
       if (row_is_network)
         {
           GtkWidget *header_name;
+          GtkWidget *network_header_spinner;
 
           g_object_set (label,
                         "margin-end", 6,
                         NULL);
 
           header_name = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0);
-          priv->network_header_spinner = gtk_spinner_new ();
-          g_object_set (priv->network_header_spinner,
+          network_header_spinner = gtk_spinner_new ();
+          g_object_set (network_header_spinner,
                         "margin-end", 12,
                         NULL);
+          g_object_bind_property (GTK_PLACES_VIEW (user_data),
+                                  "fetching-networks",
+                                  network_header_spinner,
+                                  "active",
+                                  G_BINDING_SYNC_CREATE);
+
           gtk_container_add (GTK_CONTAINER (header_name), label);
-          gtk_container_add (GTK_CONTAINER (header_name), priv->network_header_spinner);
+          gtk_container_add (GTK_CONTAINER (header_name), network_header_spinner);
           gtk_container_add (GTK_CONTAINER (header), header_name);
         }
       else
@@ -2190,6 +2200,13 @@ gtk_places_view_class_init (GtkPlacesViewClass *klass)
                                 FALSE,
                                 G_PARAM_READABLE);
 
+  properties[PROP_FETCHING_NETWORKS] =
+          g_param_spec_boolean ("fetching-networks",
+                                P_("Fetching networks"),
+                                P_("Whether the view is fetching networks"),
+                                FALSE,
+                                G_PARAM_READABLE);
+
   properties[PROP_OPEN_FLAGS] =
           g_param_spec_flags ("open-flags",
                               P_("Open Flags"),
@@ -2387,6 +2404,35 @@ gtk_places_view_get_loading (GtkPlacesView *view)
   return priv->loading;
 }
 
+static gboolean
+gtk_places_view_get_fetching_networks (GtkPlacesView *view)
+{
+  GtkPlacesViewPrivate *priv;
+
+  g_return_val_if_fail (GTK_IS_PLACES_VIEW (view), FALSE);
+
+  priv = gtk_places_view_get_instance_private (view);
+
+  return priv->fetching_networks;
+}
+
+static void
+gtk_places_view_set_fetching_networks (GtkPlacesView *view,
+                                       gboolean       fetching_networks)
+{
+  GtkPlacesViewPrivate *priv;
+
+  g_return_if_fail (GTK_IS_PLACES_VIEW (view));
+
+  priv = gtk_places_view_get_instance_private (view);
+
+  if (priv->fetching_networks != fetching_networks)
+    {
+      priv->fetching_networks = fetching_networks;
+      g_object_notify_by_pspec (G_OBJECT (view), properties [PROP_FETCHING_NETWORKS]);
+    }
+}
+
 /**
  * gtk_places_view_get_local_only:
  * @view: a #GtkPlacesView