我在市场上从我的应用程序获得用户报告,交付以下异常:

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.onKeyUp(Activity.java:2044)
at android.view.KeyEvent.dispatch(KeyEvent.java:2529)
at android.app.Activity.dispatchKeyEvent(Activity.java:2274)
at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1803)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchKeyEvent(PhoneWindow.java:1855)
at com.android.internal.policy.impl.PhoneWindow.superDispatchKeyEvent(PhoneWindow.java:1277)
at android.app.Activity.dispatchKeyEvent(Activity.java:2269)
at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1803)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.widget.TabHost.dispatchKeyEvent(TabHost.java:297)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1112)
at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchKeyEvent(PhoneWindow.java:1855)
at com.android.internal.policy.impl.PhoneWindow.superDispatchKeyEvent(PhoneWindow.java:1277)
at android.app.Activity.dispatchKeyEvent(Activity.java:2269)
at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1803)
at android.view.ViewRoot.deliverKeyEventPostIme(ViewRoot.java:2880)
at android.view.ViewRoot.handleFinishedEvent(ViewRoot.java:2853)
at android.view.ViewRoot.handleMessage(ViewRoot.java:2028)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:132)
at android.app.ActivityThread.main(ActivityThread.java:4028)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:491)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:844)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:602)
at dalvik.system.NativeStart.main(Native Method)

显然这与FragmentManager有关,而我并不使用它。堆栈跟踪没有显示任何我自己的类,所以我不知道这个异常发生在哪里以及如何防止它。

为了记录:我有一个tabhost,在每个选项卡中都有一个在活动之间切换的ActivityGroup。


当前回答

在我的情况下,我在一个叫做onActivityResult的覆盖方法中得到了这个错误。在挖掘之后,我才发现也许我之前需要打电话给“超级”。 我加进去了,效果很好

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    super.onActivityResult(requestCode, resultCode, data); //<--- THIS IS THE SUPPER CALL
    if (resultCode == Activity.RESULT_OK && requestCode == 0) {
        mostrarFragment(FiltroFragment.newInstance())
    }

}

也许你只需要在代码之前的任何重写上添加一个“super”。

其他回答

在显示片段之前检查活动是否是finished(),并注意commitAllowingStateLoss()。

例子:

if(!isFinishing()) {
FragmentManager fm = getSupportFragmentManager();
            FragmentTransaction ft = fm.beginTransaction();
            DummyFragment dummyFragment = DummyFragment.newInstance();
            ft.add(R.id.dummy_fragment_layout, dummyFragment);
            ft.commitAllowingStateLoss();
}

另一个可能的解决方法,我不确定是否在所有情况下都有帮助(来源在这里):

@Override
protected void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
        final View rootView = findViewById(android.R.id.content);
        if (rootView != null) {
            rootView.cancelPendingInputEvents();
        }
    }
}

如果你在onActivityResult中做一些FragmentTransaction,你可以做什么,你可以在onActivityResult中设置一些布尔值,然后在onResume中,你可以根据布尔值做你的FragmentTransaction。请参考下面的代码。

@Override
protected void onResume() {
    super.onResume;
    if(isSwitchFragment){
        isSwitchFragment=false;
        bottomNavigationView.getTabAt(POS_FEED).select();
    }
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == FilterActivity.FILTER_REQUEST_EVENT && data != null) {
        isSwitchFragment=true;
    }
}

Fragment事务不应该在Activity.onStop()之后执行! 检查你没有任何回调可以在onStop()之后执行事务。最好是修复原因,而不是尝试使用.commitAllowingStateLoss()等方法来绕过问题。

注意,使用transaction.commitAllowingStateLoss()可能会给用户带来糟糕的体验。有关为什么会抛出这个异常的更多信息,请参阅这篇文章。