我有一个Live Android应用程序,从市场上我收到了以下堆栈跟踪,我不知道为什么它会发生,因为它不是发生在应用程序代码中,而是由应用程序的一些或其他事件引起的(假设)

我没有使用片段,仍然有一个FragmentManager的参考。 如果有人能揭示一些隐藏的事实,以避免这类问题:

java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState
at android.app.FragmentManagerImpl.checkStateLoss(FragmentManager.java:1109)
at android.app.FragmentManagerImpl.popBackStackImmediate(FragmentManager.java:399)
at android.app.Activity.onBackPressed(Activity.java:2066)
at android.app.Activity.onKeyDown(Activity.java:1962)
at android.view.KeyEvent.dispatch(KeyEvent.java:2482)
at android.app.Activity.dispatchKeyEvent(Activity.java:2274)
at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1668)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchKeyEvent(PhoneWindow.java:1720)
at com.android.internal.policy.impl.PhoneWindow.superDispatchKeyEvent(PhoneWindow.java:1258)
at android.app.Activity.dispatchKeyEvent(Activity.java:2269)
at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1668)
at android.view.ViewRoot.deliverKeyEventPostIme(ViewRoot.java:2851)
at android.view.ViewRoot.handleFinishedEvent(ViewRoot.java:2824)
at android.view.ViewRoot.handleMessage(ViewRoot.java:2011)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:132)
at android.app.ActivityThread.main(ActivityThread.java:4025)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:491)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:841)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:599)
at dalvik.system.NativeStart.main(Native Method)  

当前回答

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

其他回答

我认为生命周期状态可以帮助防止这种崩溃从Android支持库v26.1.0开始,你可以有以下检查:

if (getLifecycle().getCurrentState().isAtLeast(Lifecycle.State.STARTED)){
  // Do fragment's transaction commit
}

或者你可以试试:

Fragment.isStateSaved()

更多信息请点击这里 https://developer.android.com/reference/android/support/v4/app/Fragment.html isStateSaved ()

我得到这个异常时,我按下后退按钮取消意图选择器在我的地图片段活动。 我通过替换onResume()的代码来解决这个问题(我在那里初始化片段和提交事务)到onStart(),应用程序现在工作正常。 希望能有所帮助。

我对这个问题的解决方案是

在片段中添加方法:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    ...
    guideMapFragment = (SupportMapFragment)a.getSupportFragmentManager().findFragmentById(R.id.guideMap);
    guideMap = guideMapFragment.getMap();
    ...
}

@Override
public void onDestroyView() {
    SherlockFragmentActivity a = getSherlockActivity();
    if (a != null && guideMapFragment != null) {
        try {
            Log.i(LOGTAG, "Removing map fragment");
            a.getSupportFragmentManager().beginTransaction().remove(guideMapFragment).commit();
            guideMapFragment = null;
        } catch(IllegalStateException e) {
            Log.i(LOGTAG, "IllegalStateException on exit");
        }
    }
    super.onDestroyView();
}

可能很糟糕,但找不到更好的了。

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();
    }
}

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)