Should only call onDetach when the widget is attached to the browser's document

java.lang.IllegalStateException:Should only call onDetach when the widget is attached to the browser's document

这个异常是在com.google.gwt.user.client.ui.Widget protected void onDetach() 方法抛出的
当页面重新加载或离开页面时会执行这个方法
如果系统没有正常初始化，会有这个异常
郁闷的是No errors in Dev Mode but Compiled localy and deployed to tomcat in errors