diff --git a/lib/sp-visualizer-row.c b/lib/sp-visualizer-row.c
index c6018884..155b0e59 100644
--- a/lib/sp-visualizer-row.c
+++ b/lib/sp-visualizer-row.c
@@ -18,7 +18,13 @@
 
 #include "sp-visualizer-row.h"
 
-G_DEFINE_ABSTRACT_TYPE (SpVisualizerRow, sp_visualizer_row, GTK_TYPE_LIST_BOX_ROW)
+typedef struct
+{
+  gint64 begin_time;
+  gint64 end_time;
+} SpVisualizerRowPrivate;
+
+G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (SpVisualizerRow, sp_visualizer_row, GTK_TYPE_LIST_BOX_ROW)
 
 static void
 sp_visualizer_row_class_init (SpVisualizerRowClass *klass)
@@ -39,3 +45,44 @@ sp_visualizer_row_set_reader (SpVisualizerRow *self,
   if (SP_VISUALIZER_ROW_GET_CLASS (self)->set_reader)
     SP_VISUALIZER_ROW_GET_CLASS (self)->set_reader (self, reader);
 }
+
+void
+sp_visualizer_row_set_time_range (SpVisualizerRow *self,
+                                  gint64           begin_time,
+                                  gint64           end_time)
+{
+  SpVisualizerRowPrivate *priv = sp_visualizer_row_get_instance_private (self);
+
+  g_return_if_fail (SP_IS_VISUALIZER_ROW (self));
+
+  if (begin_time > end_time)
+    {
+      gint64 tmp = begin_time;
+      begin_time = end_time;
+      end_time = tmp;
+    }
+
+  priv->begin_time = begin_time;
+  priv->end_time = end_time;
+
+  if (SP_VISUALIZER_ROW_GET_CLASS (self)->set_time_range)
+    SP_VISUALIZER_ROW_GET_CLASS (self)->set_time_range (self, begin_time, end_time);
+}
+
+void
+sp_visualizer_row_get_time_range (SpVisualizerRow *self,
+                                  gint64          *begin_time,
+                                  gint64          *end_time)
+{
+  SpVisualizerRowPrivate *priv = sp_visualizer_row_get_instance_private (self);
+
+  g_return_if_fail (SP_IS_VISUALIZER_ROW (self));
+  g_return_if_fail (begin_time != NULL);
+  g_return_if_fail (end_time != NULL);
+
+  if (begin_time != NULL)
+    *begin_time = priv->begin_time;
+
+  if (end_time != NULL)
+    *end_time = priv->end_time;
+}
diff --git a/lib/sp-visualizer-row.h b/lib/sp-visualizer-row.h
index fb01565c..49c828fc 100644
--- a/lib/sp-visualizer-row.h
+++ b/lib/sp-visualizer-row.h
@@ -43,6 +43,21 @@ struct _SpVisualizerRowClass
   void (*set_reader) (SpVisualizerRow *self,
                       SpCaptureReader *reader);
 
+  /**
+   * SpVisualizerRow::set_time_range:
+   * @self: A #SpVisualizerRow
+   * @begin_time: the beginning time for the row.
+   * @end_time: the end time for the row.
+   *
+   * This function is used to notify the row that the range the
+   * row should be displaying has changed. This might happen when
+   * the user has altered the zoom level, selected a region, in or
+   * a new capture was loaded.
+   */
+  void (*set_time_range) (SpVisualizerRow *self,
+                          gint64           begin_time,
+                          gint64           end_time);
+
   gpointer _reserved1;
   gpointer _reserved2;
   gpointer _reserved3;
@@ -61,8 +76,14 @@ struct _SpVisualizerRowClass
   gpointer _reserved16;
 };
 
-void sp_visualizer_row_set_reader (SpVisualizerRow *self,
-                                   SpCaptureReader *reader);
+void sp_visualizer_row_set_reader     (SpVisualizerRow *self,
+                                       SpCaptureReader *reader);
+void sp_visualizer_row_get_time_range (SpVisualizerRow *self,
+                                       gint64          *begin_time,
+                                       gint64          *end_time);
+void sp_visualizer_row_set_time_range (SpVisualizerRow *self,
+                                       gint64           begin_time,
+                                       gint64           end_time);
 
 G_END_DECLS