[evolution] EProxyEditor: Add an "Open Desktop Settings" button.

[Matthew Barnes <mbarnes src gnome org>]

commit 5dfbe39758fc1c4fd5fb2ab95689e8e82a5c34e9
Author: Matthew Barnes <mbarnes redhat com>
Date:   Fri Oct 25 16:33:31 2013 -0400

    EProxyEditor: Add an "Open Desktop Settings" button.
    
    Shown for the "Defer to Desktop Settings" choice if gnome-control-center
    is available.  The button opens gnome-control-center's "Network" panel,
    but unfortunately the "Network proxy" item cannot be selected from the
    command line.

 e-util/e-proxy-editor.c |   70 +++++++++++++++++++++++++++++++++++++++-------
 1 files changed, 59 insertions(+), 11 deletions(-)
---
diff --git a/e-util/e-proxy-editor.c b/e-util/e-proxy-editor.c
index 9ddea51..59afed1 100644
--- a/e-util/e-proxy-editor.c
+++ b/e-util/e-proxy-editor.c
@@ -52,6 +52,8 @@ struct _EProxyEditorPrivate {
        GtkWidget *socks_port_spin_button;
        GtkWidget *ignore_hosts_entry;
        GtkWidget *autoconfig_url_entry;
+
+       gchar *gcc_program_path;
 };
 
 enum {
@@ -147,6 +149,26 @@ proxy_editor_focus_out_event_cb (GtkWidget *widget,
        return FALSE;  /* propagate the event */
 }
 
+static void
+proxy_editor_open_desktop_settings_cb (GtkButton *button,
+                                       EProxyEditor *editor)
+{
+       gchar *command_line;
+       GError *local_error = NULL;
+
+       g_return_if_fail (editor->priv->gcc_program_path != NULL);
+
+       command_line = g_strdup_printf (
+               "%s network", editor->priv->gcc_program_path);
+       g_spawn_command_line_async (command_line, &local_error);
+       g_free (command_line);
+
+       if (local_error != NULL) {
+               g_warning ("%s: %s", G_STRFUNC, local_error->message);
+               g_error_free (local_error);
+       }
+}
+
 static gboolean
 proxy_editor_active_id_to_visible (GBinding *binding,
                                    const GValue *source_value,
@@ -240,6 +262,19 @@ proxy_editor_dispose (GObject *object)
 }
 
 static void
+proxy_editor_finalize (GObject *object)
+{
+       EProxyEditorPrivate *priv;
+
+       priv = E_PROXY_EDITOR_GET_PRIVATE (object);
+
+       g_free (priv->gcc_program_path);
+
+       /* Chain up to parent's finalize() method. */
+       G_OBJECT_CLASS (e_proxy_editor_parent_class)->finalize (object);
+}
+
+static void
 proxy_editor_constructed (GObject *object)
 {
        EProxyEditor *editor;
@@ -298,17 +333,26 @@ proxy_editor_constructed (GObject *object)
                GTK_COMBO_BOX_TEXT (editor->priv->method_combo_box),
                enum_value->value_nick, _("Defer to Desktop Settings"));
 
-       widget = gtk_alignment_new (0.5, 0.5, 1.0, 1.0);
-       gtk_grid_attach (GTK_GRID (editor), widget, 0, ++row, 2, 1);
-
-       g_object_bind_property_full (
-               editor->priv->method_combo_box, "active-id",
-               widget, "visible",
-               G_BINDING_DEFAULT,
-               proxy_editor_active_id_to_visible,
-               NULL,
-               (gpointer) enum_value->value_nick,
-               (GDestroyNotify) NULL);
+       if (editor->priv->gcc_program_path != NULL) {
+               widget = gtk_button_new_with_mnemonic (
+                       _("_Open Desktop Settings"));
+               gtk_widget_set_halign (widget, GTK_ALIGN_START);
+               gtk_grid_attach (GTK_GRID (editor), widget, 1, ++row, 2, 1);
+
+               g_signal_connect (
+                       widget, "clicked",
+                       G_CALLBACK (proxy_editor_open_desktop_settings_cb),
+                       editor);
+
+               g_object_bind_property_full (
+                       editor->priv->method_combo_box, "active-id",
+                       widget, "visible",
+                       G_BINDING_DEFAULT,
+                       proxy_editor_active_id_to_visible,
+                       NULL,
+                       (gpointer) enum_value->value_nick,
+                       (GDestroyNotify) NULL);
+       }
 
        /*** Manual ***/
 
@@ -535,6 +579,7 @@ e_proxy_editor_class_init (EProxyEditorClass *class)
        object_class->set_property = proxy_editor_set_property;
        object_class->get_property = proxy_editor_get_property;
        object_class->dispose = proxy_editor_dispose;
+       object_class->finalize = proxy_editor_finalize;
        object_class->constructed = proxy_editor_constructed;
 
        g_object_class_install_property (
@@ -565,6 +610,9 @@ static void
 e_proxy_editor_init (EProxyEditor *editor)
 {
        editor->priv = E_PROXY_EDITOR_GET_PRIVATE (editor);
+
+       editor->priv->gcc_program_path =
+               g_find_program_in_path ("gnome-control-center");
 }
 
 /**