Unable to add window错误

错误：

04-01 01:20:11.596: D/AndroidRuntime(1548): Shutting down VM
04-01 01:20:11.600: W/dalvikvm(1548): threadid=1: thread exiting with uncaught exception (group=0xa4d0bb20)
04-01 01:20:11.600: E/AndroidRuntime(1548): FATAL EXCEPTION: main
04-01 01:20:11.600: E/AndroidRuntime(1548): Process: com.leiting.sdk, PID: 1548
04-01 01:20:11.600: E/AndroidRuntime(1548): android.view.WindowManager$BadTokenException: Unable to add window -- token null is not valid; is your activity running?
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at android.view.ViewRootImpl.setView(ViewRootImpl.java:532)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:259)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at cn.m4399.operate.ui.widget.g.<init>(ExpandWindowLayout.java:91)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at cn.m4399.operate.control.a.b.l(PopWindowAssitant.java:105)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at cn.m4399.operate.control.accountcenter.a$1.handleMessage(AccountCenter.java:49)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at android.os.Handler.dispatchMessage(Handler.java:98)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at android.os.Looper.loop(Looper.java:136)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at android.app.ActivityThread.main(ActivityThread.java:5001)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at java.lang.reflect.Method.invokeNative(Native Method)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at java.lang.reflect.Method.invoke(Method.java:515)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
04-01 01:20:11.600: E/AndroidRuntime(1548): 	at dalvik.system.NativeStart.main(Native Method)

原因：当前activity没有配置

android:configChanges="orientation|screenSize|keyboardHidden"

，应该是在横竖屏切换时，导致activity会重新调用各个生命周期，恰好这个时候第三方调用这个activity，这个activity可能还没有重新创建完成。

解决方案：在当前activity增加一行：

android:configChanges="orientation|screenSize|keyboardHidden"

这样切屏是就不会重新创建这个activity。