这是我迄今为止遇到的最愚蠢的错误。我有一个片段应用程序工作完美的API < 11，并强制关闭API > 11。

我真的不知道他们在saveInstance调用的活动生命周期内改变了什么，但我在这里是我如何解决这个问题的:

@Override
protected void onSaveInstanceState(Bundle outState) {
    //No call for super(). Bug on API Level > 11.
}

我只是不调用.super()，一切都很好。我希望这将为您节省一些时间。

编辑:经过进一步研究，这是支持包中的一个已知错误。

如果你需要保存实例，并添加一些东西到你的outState Bundle，你可以使用以下方法:

@Override
protected void onSaveInstanceState(Bundle outState) {
    outState.putString("WORKAROUND_FOR_BUG_19917_KEY", "WORKAROUND_FOR_BUG_19917_VALUE");
    super.onSaveInstanceState(outState);
}

EDIT2:如果您试图在Activity在后台消失后执行事务，也可能会发生这种情况。为了避免这种情况，你应该使用commitAllowingStateLoss()

EDIT3: The above solutions were fixing issues in the early support.v4 libraries from what I can remember. But if you still have issues with this you MUST also read @AlexLockwood 's blog : Fragment Transactions & Activity State Loss Summary from the blog post (but I strongly recommend you to read it) : NEVER commit() transactions after onPause() on pre-Honeycomb, and onStop() on post-Honeycomb Be careful when committing transactions inside Activity lifecycle methods. Use onCreate(), onResumeFragments() and onPostResume() Avoid performing transactions inside asynchronous callback methods Use commitAllowingStateLoss() only as a last resort

当用户旋转屏幕以便加载与新方向相关的资源时，onSaveInstance将被调用。

有可能这个用户旋转了屏幕，然后按了后退按钮(因为也有可能这个用户在使用你的应用程序时摸不着他们的手机)

解决这个问题的另一种生命周期方法是使用kotlin最新发布的lifecycle-ktx。

lifecycleScope.launchWhenResumed {
    // your code with fragment or dialogfragment
}

闭包将在恢复状态后运行，因此甚至在恢复状态后调用此方法 停，等下一份简历来的时候就安全执行了。

你也可以选择喜欢

lifecycleScope.launchWhenCreated
// or
lifecycleScope.launchWhenStarted

适合你的情况。

当销毁完成时，代码将被取消。

谷歌文档链接: https://developer.android.com/kotlin/ktx#lifecycle

我认为在这些操作之前调用FragmentActivity.onStateNotSaved()可能是目前最好的选择。

这对我很管用……我自己发现的…希望对你有所帮助!

1)不要有全局的“静态”FragmentManager / FragmentTransaction。

2) onCreate，总是初始化FragmentManager再次!

样本如下:-

public abstract class FragmentController extends AnotherActivity{
protected FragmentManager fragmentManager;
protected FragmentTransaction fragmentTransaction;
protected Bundle mSavedInstanceState;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    mSavedInstanceState = savedInstanceState;
    setDefaultFragments();
}

protected void setDefaultFragments() {
    fragmentManager = getSupportFragmentManager();
    //check if on orientation change.. do not re-add fragments!
    if(mSavedInstanceState == null) {
        //instantiate the fragment manager

        fragmentTransaction = fragmentManager.beginTransaction();

        //the navigation fragments
        NavigationFragment navFrag = new NavigationFragment();
        ToolbarFragment toolFrag = new ToolbarFragment();

        fragmentTransaction.add(R.id.NavLayout, navFrag, "NavFrag");
        fragmentTransaction.add(R.id.ToolbarLayout, toolFrag, "ToolFrag");
        fragmentTransaction.commitAllowingStateLoss();

        //add own fragment to the nav (abstract method)
        setOwnFragment();
    }
}

你可以使用FragmentActivity。onStart在popBackStackImmediate之前

是这样的:

public void backStackFragment() {
    this.start();
    getFragmentManager().popBackStackImmediate();
}

public void start(){
    FragmentActivity a = getActivity();
    if(a instanceof DepositPlanPadActivity){
      ((DepositPlanPadActivity)a).onStart();
    }
    if(a instanceof SmallChangePlanPad){
            ((SmallChangePlanPad)a).onStart();
        }
        if(a instanceof UserCenterActivity){
            ((UserCenterActivity)a).onStart();
        }
    }

http://jorryliu.blogspot.com/2014/09/illegalstateexception-can-not-perform.html