解決onSaveInstanceState的Bug

Bug:

java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState
     at android.support.v4.app.FragmentManagerImpl.checkStateLoss(Unknown Source)
     at android.support.v4.app.FragmentManagerImpl.enqueueAction(Unknown Source)
     at android.support.v4.app.BackStackRecord.commitInternal(Unknown Source)
     at android.support.v4.app.BackStackRecord.commit(Unknown Source)
     at android.support.v4.app.FragmentTabHost.onAttachedToWindow(Unknown Source)
     at android.view.View.dispatchAttachedToWindow(View.java:12618)
     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2460)
     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2467)
     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2467)
     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2467)
     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2467)
     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:2467)
     at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1262)
     at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1045)
     at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5908)
     at android.view.Choreographer$CallbackRecord.run(Choreographer.java:780)
     at android.view.Choreographer.doCallbacks(Choreographer.java:593)
     at android.view.Choreographer.doFrame(Choreographer.java:562)
     at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:766)
     at android.os.Handler.handleCallback(Handler.java:733)
     at android.os.Handler.dispatchMessage(Handler.java:95)
     at android.os.Looper.loop(Looper.java:136)
     at android.app.ActivityThread.main(ActivityThread.java:5336)
     at java.lang.reflect.Method.invokeNative(Native Method)
     at java.lang.reflect.Method.invoke(Method.java:515)
     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865)
     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:681)
     at dalvik.system.NativeStart.main(Native Method)
解決:在重載onSaveInstanceState()中，不調用super()方法，因爲調用super方法，在API level大於11時，可能導致崩潰。
@Override
protected void onSaveInstanceState(Bundle outState) {
    //No call for super(). Bug on API Level > 11.
//        super.onSaveInstanceState(outState);
}
onSaveInstanceState()方法的作用: 
onSaveInstanceState的調用遵循原則，即當系統“未經用戶許可”時銷燬activity，則onSaveInstanceState會被系統調用。
這是系統的責任，因爲它必須要提供一個機會讓用戶保存數據。

super.onSaveInstanceState(outState)：
活動本身會在bundle中存入一些值，例如fragments的狀態，如果沒有調用super方法，這些值不會被保存，但也不會使程序崩潰。