add user_data in rtgui_widget.

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@778 bbd45198-f89e-11dd-88c7-29a3b14d5316

components/rtgui/widgets/widget.c

@@ -10,7 +10,9 @@
  * Change Logs:
  * Date           Author       Notes
  * 2009-10-04     Bernard      first version
+ * 2010-06-26     Bernard      add user_data to widget structure
  */
+
 #include <rtgui/widgets/widget.h>
 #include <rtgui/widgets/window.h>
 #include <rtgui/widgets/view.h>
@@ -53,6 +55,9 @@ static void _rtgui_widget_constructor(rtgui_widget_t *widget)
 	/* set default event handler */
 	widget->event_handler = rtgui_widget_event_handler;
 
+	/* init user data private to 0 */
+	widget->user_data = 0;
+
 	/* init clip information */
 	rtgui_region_init(&(widget->clip));
 }