IllegalStateException：活动已被销毁

Question

我有以下代码

  @Override
  public void updateSubFragments() {
    Fragment myFragment1 = getFragment1();
    Fragment myFragment2 = getFragment2();

    if (isTrue) {
      getFragmentManager().beginTransaction().hide(myFragment2).show(myFragment1).commitAllowingStateLoss();
    } else {
      getFragmentManager().beginTransaction().hide(myFragment1).show(myFragment2).commitAllowingStateLoss();
    }
  }


 private MyFragment getFragment1() {
    MyFragment myFragment = (MyFragment) getChildFragmentManager()
        .findFragmentByTag(MY_FRAGMENT);
    if (myFragment == null) {
        myFragment = new MyFragment();
        getChildFragmentManager().beginTransaction()
         .add(R.id.myFragment, myFragment, MY_FRAGMENT).commit();
    }
    return myFragment;
  }

并获得此例外

java.lang.IllegalStateException: Activity has been destroyed
at android.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1333)
at android.app.BackStackRecord.commitInternal(BackStackRecord.java:595)
at android.app.BackStackRecord.commit(BackStackRecord.java:574)

我认为原因可能是Fragment引用了被破坏的Activity，但是，Fragment刚刚被创建，因为它之前是null。任何想法为什么会发生此异常或如何解决它？