后台应用程序是一个怎样的过程，所以你应该改为延长延长的UIApplication中的应用。在主类中实现你所有的code。您还可以看到一个例子这个***的问题：Blackberry - 运行后台应用程序

Background Application is a kind of process so you should extend Application instead of extending Uiapplication . In your main class implement all your code. You can also see this *** question for an example: Blackberry - Running Background Application