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。
芬兰湾的科特林扩展
fun FragmentManager?.replaceAndAddToBackStack(
@IdRes containerViewId: Int,
fragment: () -> Fragment,
tag: String
) {
// Find and synchronously remove a fragment with the same tag.
// The second transaction must start after the first has finished.
this?.findFragmentByTag(tag)?.let {
beginTransaction().remove(it).commitNow()
}
// Add a fragment.
this?.beginTransaction()?.run {
replace(containerViewId, fragment, tag)
// The next line will add the fragment to a back stack.
// Remove if not needed.
// You can use null instead of tag, but tag is needed for popBackStack(),
// see https://stackoverflow.com/a/59158254/2914140
addToBackStack(tag)
}?.commitAllowingStateLoss()
}
用法:
val fragment = { SomeFragment.newInstance(data) }
fragmentManager?.replaceAndAddToBackStack(R.id.container, fragment, SomeFragment.TAG)
我知道@Ovidiu Latcu有一个公认的答案,但过了一段时间,错误仍然存在。
@Override
protected void onSaveInstanceState(Bundle outState) {
//No call for super(). Bug on API Level > 11.
}
Crashlytics仍然给我发送这个奇怪的错误信息。
但是错误现在只发生在版本7+(牛轧糖)
我的修复方法是在fragmentTransaction中使用commitAllowingStateLoss()而不是commit()。
这篇文章对commitAllowingStateLoss()有帮助,并且再也没有片段问题了。
总而言之,这里公认的答案可能适用于牛轧糖之前的安卓版本。
这可能会节省一些人几个小时的搜索时间。
幸福的准则。< 3干杯
请在这里检查我的答案。基本上我只需要:
@Override
protected void onSaveInstanceState(Bundle outState) {
//No call for super(). Bug on API Level > 11.
}
不要在saveInstanceState方法上调用super()。这把事情搞砸了……
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outState Bundle中,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);
}
最后,正确的解决方案是(如评论所示)使用:
transaction.commitAllowingStateLoss();
当添加或执行导致异常的FragmentTransaction时。
@Gian Gomen在我的案例中,SUPER解决了问题。这似乎是比commitAllowingStateLoss()更正确的解决方案,因为它解决了问题,而不是隐藏它。
@Override
public void onRequestPermissionsResult(
final int requestCode,
@NonNull final String[] permissions,
@NonNull final int[] grantResults
) {
super.onRequestPermissionsResult(requestCode,permissions, grantResults); //<--- Without this line crash
switch (requestCode) {
case Constants.REQUEST_CODE_PERMISSION_STORAGE:
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
onPermissionGranted(Constants.REQUEST_CODE_PERMISSION_STORAGE);
}
break;
}
我最终创建了一个基本片段,并使我的应用程序中的所有片段扩展它
public class BaseFragment extends Fragment {
private boolean mStateSaved;
@CallSuper
@Override
public void onSaveInstanceState(Bundle outState) {
mStateSaved = true;
super.onSaveInstanceState(outState);
}
/**
* Version of {@link #show(FragmentManager, String)} that no-ops when an IllegalStateException
* would otherwise occur.
*/
public void showAllowingStateLoss(FragmentManager manager, String tag) {
// API 26 added this convenient method
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
if (manager.isStateSaved()) {
return;
}
}
if (mStateSaved) {
return;
}
show(manager, tag);
}
}
然后,当我试图显示一个片段时,我使用showAllowingStateLoss而不是show
是这样的:
MyFragment.newInstance()
.showAllowingStateLoss(getFragmentManager(), MY_FRAGMENT.TAG);
我从这个PR上找到了这个解决方案:https://github.com/googlesamples/easypermissions/pull/170/files