diff --git a/src/ag-window.c b/src/ag-window.c
index befaa67..9c45114 100644
--- a/src/ag-window.c
+++ b/src/ag-window.c
@@ -333,3 +333,17 @@ ag_window_new(AgApp *app)
     return GTK_WIDGET(window);
 }
 
+void
+ag_window_set_chart(AgWindow *window, AgChart *chart)
+{
+    g_object_unref(window->priv->chart);
+    window->priv->chart = chart;
+    g_object_ref(chart);
+}
+
+AgChart *
+ag_window_get_chart(AgWindow *window)
+{
+    return window->priv->chart;
+}
+
diff --git a/src/ag-window.h b/src/ag-window.h
index a1780c4..37590eb 100644
--- a/src/ag-window.h
+++ b/src/ag-window.h
@@ -3,6 +3,7 @@
 
 #include <gtk/gtk.h>
 #include "ag-app.h"
+#include "ag-chart.h"
 
 G_BEGIN_DECLS
 
@@ -28,6 +29,8 @@ struct _AgWindowClass {
 
 GType ag_window_get_type(void) G_GNUC_CONST;
 GtkWidget *ag_window_new(AgApp *app);
+void ag_window_set_chart(AgWindow *window, AgChart *chart);
+AgChart *ag_window_get_chart(AgWindow *window);
 
 G_END_DECLS