at android.support.v4.app.FragmentManagerImpl.detachFragment (FragmentManagerImpl.java)
  or                     .saveAllState (FragmentManagerImpl.java)
  at android.support.v4.app.FragmentController.saveAllState (FragmentController.java)
  at android.support.v4.app.FragmentActivity.onSaveInstanceState (FragmentActivity.java)
  at android.support.v7.app.AppCompatActivity.onSaveInstanceState (AppCompatActivity.java)
  at android.app.Activity.performSaveInstanceState (Activity.java:1337)
  at android.app.Instrumentation.callActivityOnSaveInstanceState (Instrumentation.java:1300)
  at android.app.ActivityThread.callCallActivityOnSaveInstanceState (ActivityThread.java:4131)
  at android.app.ActivityThread.performStopActivityInner (ActivityThread.java:3528)
  at android.app.ActivityThread.handleStopActivity (ActivityThread.java:3588)
  at android.app.ActivityThread.access$1200 (ActivityThread.java:165)
  at android.app.ActivityThread$H.handleMessage (ActivityThread.java:1404)
  at android.os.Handler.dispatchMessage (Handler.java:102)
  at android.os.Looper.loop (Looper.java:150)
  at android.app.ActivityThread.main (ActivityThread.java:5621)
  at java.lang.reflect.Method.invoke (Method.java)
  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:794)
  at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:684)