手柄连接断开时， 后台运行的activity被重新加载

今天遇到了一个问题，手机连接手柄和断开连接时， activity被重新create， 里面的数据出现了错误，结果界面异常。

原因分析： 在manifest中没有声明相应的config， 导致在系统没有调用onConfigurationChanged, 而是destroy掉了activity，

让我们来看看api中是怎么说的：

* Called by the system when the device configuration changes while your
* activity is running.  Note that this will <em>only</em> be called if
* you have selected configurations you would like to handle with the
* {@link android.R.attr#configChanges} attribute in your manifest.  If
* any configuration change occurs that is not selected to be reported
* by that attribute, then instead of reporting it the system will stop
* and restart the activity (to have it launched with the new
* configuration).

所以需要在manifest中添加属性：

android:configChanges="keyboard|keyboardHidden"