map: defer adjustment changes to next frame

This helps ensure that we are not handling changes to GtkAdjustment that
happen during the LAYOUT phase of the frame clock.

Instead we defer it to the next frame as it's too late to affect any sort
of allocations on this frame.

1 files changed, 38 insertions, 3 deletions

diff --git a/gtksourceview/gtksourcemap.c b/gtksourceview/gtksourcemap.c
index 708eb338..26043cfe 100644
--- a/gtksourceview/gtksourcemap.c
+++ b/gtksourceview/gtksourcemap.c
@@ -202,6 +202,11 @@ typedef struct
 	/* Signals connected indirectly to the buffer */
 	gulong buffer_notify_style_scheme_handler;
 
+	/* Tick callback to queue work until the next frame to
+	 * avoid doing changes during LAYOUT phase.
+	 */
+	guint update_id;
+
 	/* Denotes if we are in a grab from button press */
 	guint in_press : 1;
 
@@ -519,6 +524,37 @@ update_child_vadjustment (GtkSourceMap *map)
 	}
 
 	gtk_adjustment_set_value (child_vadj, new_value);
+
+	gtk_widget_queue_allocate (GTK_WIDGET (map));
+}
+
+static gboolean
+gtk_source_map_do_update (GtkWidget     *widget,
+                          GdkFrameClock *frame_clock,
+			  gpointer       user_data)
+{
+	GtkSourceMap *map = GTK_SOURCE_MAP (widget);
+	GtkSourceMapPrivate *priv = gtk_source_map_get_instance_private (map);
+
+	priv->update_id = 0;
+	update_child_vadjustment (map);
+	return G_SOURCE_REMOVE;
+}
+
+static void
+gtk_source_map_queue_update (GtkSourceMap *map)
+{
+	GtkSourceMapPrivate *priv = gtk_source_map_get_instance_private (map);
+
+	g_assert (GTK_SOURCE_IS_MAP (map));
+
+	if (priv->update_id == 0)
+	{
+		priv->update_id =
+			gtk_widget_add_tick_callback (GTK_WIDGET (map),
+			                              gtk_source_map_do_update,
+			                              NULL, NULL);
+	}
 }
 
 static void
@@ -531,8 +567,7 @@ view_vadj_value_changed (GtkSourceMap  *map,
 	if (value != priv->last_vadj_value)
 	{
 		priv->last_vadj_value = value;
-		update_child_vadjustment (map);
-		gtk_widget_queue_allocate (GTK_WIDGET (map));
+		gtk_source_map_queue_update (map);
 	}
 }
 
@@ -547,7 +582,7 @@ view_vadj_notify_upper (GtkSourceMap  *map,
 	if (upper != priv->last_vadj_upper)
 	{
 		priv->last_vadj_upper = upper;
-		gtk_widget_queue_allocate (GTK_WIDGET (map));
+		gtk_source_map_queue_update (map);
 	}
 }