您需要使用 @ + ID 当你要定义你自己的ID到一个视图，这在这种情况下是 section_spinner 。而 @android：ID 当你需要在架构设置视图的ID Android的pre-定义的ID被使用。对于例如，当使用ListActivity，TabWidget /的FrameLayout在TabHost等。

You need to use @+id when you are defining your own Id to a view, which in this case is section_spinner. And @android:id is used when you need to set an Id of a view to android's pre-defined Id in framework. for e.g when using ListActivity, TabWidget/FrameLayout in TabHost and etc.