[gnome-builder] messages: use signal group for signal

[Christian Hergert <chergert src gnome org>]

commit 287919935a3338ccf101cffae6485b0554db8951
Author: Christian Hergert <chergert redhat com>
Date:   Tue Jan 9 15:42:00 2018 -0800

    messages: use signal group for signal
    
    This just helps protect against multiple calls to set the context or a
    NULL value for the context.

 src/plugins/messages/gbp-messages-panel.c |   32 ++++++++++++++++++++++------
 1 files changed, 25 insertions(+), 7 deletions(-)
---
diff --git a/src/plugins/messages/gbp-messages-panel.c b/src/plugins/messages/gbp-messages-panel.c
index fbfa7fa..49c9454 100644
--- a/src/plugins/messages/gbp-messages-panel.c
+++ b/src/plugins/messages/gbp-messages-panel.c
@@ -26,6 +26,8 @@ struct _GbpMessagesPanel
 {
   DzlDockWidget parent_instance;
 
+  DzlSignalGroup *signals;
+
   GtkScrollbar *scrollbar;
   IdeTerminal  *terminal;
 };
@@ -65,16 +67,22 @@ gbp_messages_panel_set_context (GtkWidget  *widget,
   g_assert (GBP_IS_MESSAGES_PANEL (self));
   g_assert (!context || IDE_IS_CONTEXT (context));
 
+  dzl_signal_group_set_target (self->signals, context);
+
 #if 0
-  g_timeout_add (1000, do_log, context);
+  if (context != NULL)
+    g_timeout_add (1000, do_log, context);
 #endif
+}
 
-  if (context != NULL)
-    g_signal_connect_object (context,
-                             "log",
-                             G_CALLBACK (gbp_messages_panel_log_cb),
-                             self,
-                             G_CONNECT_SWAPPED);
+static void
+gbp_messages_panel_destroy (GtkWidget *widget)
+{
+  GbpMessagesPanel *self = (GbpMessagesPanel *)widget;
+
+  g_clear_object (&self->signals);
+
+  GTK_WIDGET_CLASS (gbp_messages_panel_parent_class)->destroy (widget);
 }
 
 static void
@@ -82,6 +90,8 @@ gbp_messages_panel_class_init (GbpMessagesPanelClass *klass)
 {
   GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
 
+  widget_class->destroy = gbp_messages_panel_destroy;
+
   gtk_widget_class_set_template_from_resource (widget_class,
                                                
"/org/gnome/builder/plugins/messages-plugin/gbp-messages-panel.ui");
   gtk_widget_class_bind_template_child (widget_class, GbpMessagesPanel, scrollbar);
@@ -99,4 +109,12 @@ gbp_messages_panel_init (GbpMessagesPanel *self)
 
   vadj = gtk_scrollable_get_vadjustment (GTK_SCROLLABLE (self->terminal));
   gtk_range_set_adjustment (GTK_RANGE (self->scrollbar), vadj);
+
+  self->signals = dzl_signal_group_new (IDE_TYPE_CONTEXT);
+
+  dzl_signal_group_connect_object (self->signals,
+                                   "log",
+                                   G_CALLBACK (gbp_messages_panel_log_cb),
+                                   self,
+                                   G_CONNECT_SWAPPED);
 }