java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState
Solution 1
You should do the transaction in a Handler
as follows:
@Override
protected void onPostExecute(String result) {
Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPostExecute");
new Handler().post(new Runnable() {
public void run() {
fm = getSupportFragmentManager();
ft = fm.beginTransaction();
ft.remove(dummyFragment);
ft.commit();
}
});
}
Solution 2
Thanks Oleg Vaskevich. Using a WeakReference
of the FragmentActivity
solved the problem. My code looks as follows now:
public class MyFragmentActivity extends FragmentActivity implements OnFriendAddedListener {
private static WeakReference<MyFragmentActivity> wrActivity = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
wrActivity = new WeakReference<MyFragmentActivity>(this);
...
private class onFriendAddedAsyncTask extends AsyncTask<String, Void, String> {
@Override
protected void onPreExecute() {
FragmentManager fm = getSupportFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
DummyFragment dummyFragment = DummyFragment.newInstance();
ft.add(R.id.dummy_fragment_layout, dummyFragment);
ft.commit();
}
@Override
protected void onPostExecute(String result) {
final Activity activity = wrActivity.get();
if (activity != null && !activity.isFinishing()) {
FragmentManager fm = activity.getSupportFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
DummyFragment dummyFragment = (DummyFragment) fm.findFragmentById(R.id.dummy_fragment_layout);
ft.remove(dummyFragment);
ft.commitAllowingStateLoss();
}
}
Solution 3
I believe the correct answer to this question is the following method.
public abstract int commitAllowingStateLoss ()
Like commit() but allows the commit to be executed after an activity's state is saved. This is dangerous because the commit can be lost if the activity needs to later be restored from its state, so this should only be used for cases where it is okay for the UI state to change unexpectedly on the user.
The above description relates to this method.
protected void onSaveInstanceState(android.os.Bundle outState)
This problem occurs precisely when the device goes to sleep.
http://developer.android.com/reference/android/app/FragmentTransaction.html
Solution 4
Short And working Solution :
Follow Simple Steps :
Step 1 : Override onSaveInstanceState
state in respective fragment. And remove super method from it.
@Override
public void onSaveInstanceState(Bundle outState) {
}
Step 2 : Use CommitAllowingStateLoss();
instead of commit();
while fragment operations.
fragmentTransaction.commitAllowingStateLoss();
Solution 5
Check if the activity isFinishing()
before showing the fragment.
Example:
if(!isFinishing()) {
FragmentManager fm = getSupportFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
DummyFragment dummyFragment = DummyFragment.newInstance();
ft.add(R.id.dummy_fragment_layout, dummyFragment);
ft.commitAllowingStateLoss();
}
samo
Updated on July 04, 2020Comments
-
samo almost 4 years
I'm using the support library for my app. In my FragmentActivity I'm using an AsyncTask for downloading data from internet. In the onPreExecute() method I add a Fragment and in the onPostExecute() method I remove it again. When the orientation is changed in between, I get the above mentioned exception. Please take a look at the details:
private class onFriendAddedAsyncTask extends AsyncTask<String, Void, String> { DummyFragment dummyFragment; FragmentManager fm; FragmentTransaction ft; @Override protected void onPreExecute() { Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPreExecute"); dummyFragment = DummyFragment.newInstance(); fm = getSupportFragmentManager(); ft = fm.beginTransaction(); ft.add(dummyFragment, "dummy_fragment"); ft.commit(); } @Override protected void onPostExecute(String result) { Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPostExecute"); ft = fm.beginTransaction(); ft.remove(dummyFragment); ft.commit(); } @Override protected String doInBackground(String... name) { Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/doInBackground"); ... }
I get following LogCut:
01-05 23:54:19.958: V/MyFragmentActivity(12783): onFriendAddedAsyncTask/onPreExecute 01-05 23:54:19.968: V/DummyFragment(12783): onAttach 01-05 23:54:19.968: V/DummyFragment(12783): onCreate 01-05 23:54:19.968: V/MyFragmentActivity(12783): onFriendAddedAsyncTask/doInBackground 01-05 23:54:19.973: V/DummyFragment(12783): onCreateView 01-05 23:54:19.973: V/DummyFragment(12783): onActivityCreated 01-05 23:54:19.973: V/DummyFragment(12783): onStart 01-05 23:54:19.973: V/DummyFragment(12783): onResume 01-05 23:54:21.933: V/MyFragmentActivity(12783): onSaveInstanceState 01-05 23:54:21.933: V/DummyFragment(12783): onSaveInstanceState 01-05 23:54:21.933: V/MyFragmentActivity(12783): onPause 01-05 23:54:21.933: V/DummyFragment(12783): onPause 01-05 23:54:21.938: V/MyFragmentActivity(12783): onStop 01-05 23:54:21.938: V/DummyFragment(12783): onStop 01-05 23:54:21.938: V/MyFragmentActivity(12783): onDestroy 01-05 23:54:21.938: V/DummyFragment(12783): onDestroyView 01-05 23:54:21.938: V/DummyFragment(12783): onDestroy 01-05 23:54:21.938: V/DummyFragment(12783): onDetach 01-05 23:54:21.978: V/MyFragmentActivity(12783): onCreate 01-05 23:54:21.978: V/DummyFragment(12783): onAttach 01-05 23:54:21.978: V/DummyFragment(12783): onCreate 01-05 23:54:22.263: V/MyFragmentActivity(12783): onStart 01-05 23:54:22.313: V/DummyFragment(12783): onCreateView 01-05 23:54:22.313: V/DummyFragment(12783): onActivityCreated 01-05 23:54:22.313: V/DummyFragment(12783): onStart 01-05 23:54:22.323: V/MyFragmentActivity(12783): onResume 01-05 23:54:22.323: V/MyFragmentActivity(12783): onPostResume 01-05 23:54:22.323: V/MyFragmentActivity(12783): onResumeFragments 01-05 23:54:22.323: V/DummyFragment(12783): onResume 01-05 23:54:27.123: V/MyFragmentActivity(12783): onFriendAddedAsyncTask/onPostExecute 01-05 23:54:27.123: D/AndroidRuntime(12783): Shutting down VM 01-05 23:54:27.123: W/dalvikvm(12783): threadid=1: thread exiting with uncaught exception (group=0x4001d7d0) 01-05 23:54:27.138: E/AndroidRuntime(12783): FATAL EXCEPTION: main 01-05 23:54:27.138: E/AndroidRuntime(12783): java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState 01-05 23:54:27.138: E/AndroidRuntime(12783): at android.support.v4.app.FragmentManagerImpl.checkStateLoss(FragmentManager.java:1314) 01-05 23:54:27.138: E/AndroidRuntime(12783): at android.support.v4.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1325) 01-05 23:54:27.138: E/AndroidRuntime(12783): at android.support.v4.app.BackStackRecord.commitInternal(BackStackRecord.java:548) 01-05 23:54:27.138: E/AndroidRuntime(12783): at android.support.v4.app.BackStackRecord.commit(BackStackRecord.java:532) 01-05 23:54:27.138: E/AndroidRuntime(12783): at com.xyz.dummy.MyFragmentActivity$onFriendAddedAsyncTask.onPostExecute(MyFragmentActivity.java:447) 01-05 23:54:27.138: E/AndroidRuntime(12783): at com.xyz.dummy.MyFragmentActivity$onFriendAddedAsyncTask.onPostExecute(MyFragmentActivity.java:1) 01-05 23:54:27.138: E/AndroidRuntime(12783): at android.os.AsyncTask.finish(AsyncTask.java:417) 01-05 23:54:27.138: E/AndroidRuntime(12783): at android.os.AsyncTask.access$300(AsyncTask.java:127) 01-05 23:54:27.138: E/AndroidRuntime(12783): at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:429) 01-05 23:54:27.138: E/AndroidRuntime(12783): at android.os.Handler.dispatchMessage(Handler.java:99) 01-05 23:54:27.138: E/AndroidRuntime(12783): at android.os.Looper.loop(Looper.java:123) 01-05 23:54:27.138: E/AndroidRuntime(12783): at android.app.ActivityThread.main(ActivityThread.java:4627) 01-05 23:54:27.138: E/AndroidRuntime(12783): at java.lang.reflect.Method.invokeNative(Native Method) 01-05 23:54:27.138: E/AndroidRuntime(12783): at java.lang.reflect.Method.invoke(Method.java:521) 01-05 23:54:27.138: E/AndroidRuntime(12783): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858) 01-05 23:54:27.138: E/AndroidRuntime(12783): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 01-05 23:54:27.138: E/AndroidRuntime(12783): at dalvik.system.NativeStart.main(Native Method)
In other threads about similar problems the reason seems to be that the onPostExecute method is called before the onResume() method is called. But I get the exception even though onResume() is called before.
Does someone knows what's wrong?
The Activity looks like this:
public class MyFragmentActivity extends FragmentActivity implements OnFriendSelectedListener, OnFriendAddedListener, OnFriendOptionSelectedListener, LoaderCallbacks<Cursor> { @Override public void onCreate(Bundle savedInstanceState) { Log.v("MyFragmentActivity", "onCreate"); super.onCreate(savedInstanceState); setContentView(R.layout.fragment_activity_layout); FragmentManager fm = getSupportFragmentManager(); FragmentTransaction ft = fm.beginTransaction(); FriendListFragment friendListFragment = (FriendListFragment)fm.findFragmentById(R.id.friend_list_fragment_layout); if (friendListFragment == null) { friendListFragment = new FriendListFragment(); ft.add(R.id.friend_list_fragment_layout, friendListFragment); ft.commit(); fm.executePendingTransactions(); startService(new Intent(this, MyIntentService.class)); getSupportLoaderManager().initLoader(CHECK_EMPTY_DATABASE, null, this); } } @Override public boolean onCreateOptionsMenu(Menu menu) { super.onCreateOptionsMenu(menu); getMenuInflater().inflate(R.menu.fragment_activity_options_menu, menu); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { super.onOptionsItemSelected(item); switch (item.getItemId()) { case R.id.add_friend_menu_item: AddFriendDialogFragment addFriendDialogFragment = AddFriendDialogFragment.newInstance(); addFriendDialogFragment.show(getSupportFragmentManager(), "add_friend_dialog_fragment"); return true; default: return false; } } @Override public void onFriendAdded(String name) { name = name.trim(); if (name.length() > 0) { new onFriendAddedAsyncTask().execute(name); } }
When using commitAllowingStateLoss() I get the following exception:
01-06 14:54:29.548: E/AndroidRuntime(18020): FATAL EXCEPTION: main 01-06 14:54:29.548: E/AndroidRuntime(18020): java.lang.IllegalStateException: Activity has been destroyed 01-06 14:54:29.548: E/AndroidRuntime(18020): at android.support.v4.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1329) 01-06 14:54:29.548: E/AndroidRuntime(18020): at android.support.v4.app.BackStackRecord.commitInternal(BackStackRecord.java:548) 01-06 14:54:29.548: E/AndroidRuntime(18020): at android.support.v4.app.BackStackRecord.commitAllowingStateLoss(BackStackRecord.java:536) 01-06 14:54:29.548: E/AndroidRuntime(18020): at com.xyz.dummy.FadiaFragmentActivity$onFriendAddedAsyncTask.onPostExecute(FadiaFragmentActivity.java:461) 01-06 14:54:29.548: E/AndroidRuntime(18020): at com.xyz.dummy.FadiaFragmentActivity$onFriendAddedAsyncTask.onPostExecute(FadiaFragmentActivity.java:1) 01-06 14:54:29.548: E/AndroidRuntime(18020): at android.os.AsyncTask.finish(AsyncTask.java:417) 01-06 14:54:29.548: E/AndroidRuntime(18020): at android.os.AsyncTask.access$300(AsyncTask.java:127) 01-06 14:54:29.548: E/AndroidRuntime(18020): at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:429) 01-06 14:54:29.548: E/AndroidRuntime(18020): at android.os.Handler.dispatchMessage(Handler.java:99) 01-06 14:54:29.548: E/AndroidRuntime(18020): at android.os.Looper.loop(Looper.java:123) 01-06 14:54:29.548: E/AndroidRuntime(18020): at android.app.ActivityThread.main(ActivityThread.java:4627) 01-06 14:54:29.548: E/AndroidRuntime(18020): at java.lang.reflect.Method.invokeNative(Native Method) 01-06 14:54:29.548: E/AndroidRuntime(18020): at java.lang.reflect.Method.invoke(Method.java:521) 01-06 14:54:29.548: E/AndroidRuntime(18020): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858) 01-06 14:54:29.548: E/AndroidRuntime(18020): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 01-06 14:54:29.548: E/AndroidRuntime(18020): at dalvik.system.NativeStart.main(Native Method)
I get the same IllegalStateExeption when I implement the AsynTask as follows, because the findFragmentById() method returns a null pointer.
private class onFriendAddedAsyncTask extends AsyncTask<String, Void, String> { protected void onPreExecute() { Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPreExecute"); FragmentManager fm = getSupportFragmentManager(); FragmentTransaction ft = fm.beginTransaction(); DummyFragment dummyFragment = DummyFragment.newInstance(); ft.add(R.id.dummy_fragment_layout, dummyFragment); ft.commit(); } protected void onPostExecute(String result) { Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPostExecute"); FragmentManager fm = getSupportFragmentManager(); FragmentTransaction ft = fm.beginTransaction(); DummyFragment dummyFragment = (DummyFragment) fm.findFragmentById(R.id.dummy_fragment_layout); ft.remove(dummyFragment); ft.commitAllowingStateLoss(); }
In the next step I use a handler for the adding and removing the DummyFragment. Additionally I've added some more debug output.
private class onFriendAddedAsyncTask extends AsyncTask<String, Void, String> { @Override protected void onPreExecute() { Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPreExecute " + getSupportFragmentManager()); Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPreExecute " + getSupportFragmentManager().findFragmentById(R.id.dummy_fragment_layout)); Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPreExecute " + getSupportFragmentManager().findFragmentById(R.id.friend_list_fragment_layout)); new Handler().post(new Runnable() { public void run() { Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPreExecute " + getSupportFragmentManager()); Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPreExecute " + getSupportFragmentManager().findFragmentById(R.id.dummy_fragment_layout)); Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPreExecute " + getSupportFragmentManager().findFragmentById(R.id.friend_list_fragment_layout)); FragmentManager fm = getSupportFragmentManager(); FragmentTransaction ft = fm.beginTransaction(); DummyFragment dummyFragment = DummyFragment.newInstance(); ft.add(R.id.dummy_fragment_layout, dummyFragment); ft.commit(); } }); @Override protected void onPostExecute(String result) { Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPostExecute " + getSupportFragmentManager()); Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPostExecute " + getSupportFragmentManager().findFragmentById(R.id.dummy_fragment_layout)); Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPostExecute " + getSupportFragmentManager().findFragmentById(R.id.friend_list_fragment_layout)); new Handler().post(new Runnable() { public void run() { Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPostExecute " + getSupportFragmentManager()); Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPostExecute " + getSupportFragmentManager().findFragmentById(R.id.dummy_fragment_layout)); Log.v("MyFragmentActivity", "onFriendAddedAsyncTask/onPostExecute " + getSupportFragmentManager().findFragmentById(R.id.friend_list_fragment_layout)); FragmentManager fm = getSupportFragmentManager(); FragmentTransaction ft = fm.beginTransaction(); DummyFragment dummyFragment = (DummyFragment) fm.findFragmentById(R.id.dummy_fragment_layout); ft.remove(dummyFragment); ft.commitAllowingStateLoss(); } });
I get following LogCut:
01-07 19:00:17.273: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/onPreExecute FragmentManager{45e384a8 in MyFragmentActivity{45e38358}} 01-07 19:00:17.273: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/onPreExecute null 01-07 19:00:17.273: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/onPreExecute FriendListFragment{45e38ab0 #0 id=0x7f0a0002} 01-07 19:00:17.283: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/onPreExecute FragmentManager{45e384a8 in MyFragmentActivity{45e38358}} 01-07 19:00:17.288: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/doInBackground 01-07 19:00:17.288: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/onPreExecute null 01-07 19:00:17.288: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/onPreExecute FriendListFragment{45e38ab0 #0 id=0x7f0a0002} 01-07 19:00:17.308: V/DummyFragment(4124): onAttach DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:17.308: V/DummyFragment(4124): onCreate DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:17.308: V/DummyFragment(4124): onCreateView DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:17.308: V/DummyFragment(4124): onActivityCreated DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:17.308: V/DummyFragment(4124): onStart DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:17.313: V/DummyFragment(4124): onResume DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:18.098: V/MyFragmentActivity(4124): onSaveInstanceState DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:18.098: V/DummyFragment(4124): onSaveInstanceState DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:18.098: V/MyFragmentActivity(4124): onPause DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:18.098: V/DummyFragment(4124): onPause DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:18.103: V/MyFragmentActivity(4124): onStop DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:18.103: V/DummyFragment(4124): onStop DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:18.103: V/MyFragmentActivity(4124): onDestroy DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:18.103: V/DummyFragment(4124): onDestroyView DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:18.108: V/DummyFragment(4124): onDestroy DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:18.113: V/DummyFragment(4124): onDetach DummyFragment{45dd7498 #2 id=0x7f0a0004} 01-07 19:00:18.138: V/MyFragmentActivity(4124): onCreate 01-07 19:00:18.138: V/FriendListFragment(4124): FriendListFragment 01-07 19:00:18.138: V/FriendListFragment(4124): onAttach FriendListFragment{45e4a7f8 #0 id=0x7f0a0002} 01-07 19:00:18.138: V/FriendListFragment(4124): onCreate FriendListFragment{45e4a7f8 #0 id=0x7f0a0002} 01-07 19:00:18.148: V/DummyFragment(4124): onAttach DummyFragment{45d7d1a0 #2 id=0x7f0a0004} 01-07 19:00:18.153: V/DummyFragment(4124): onCreate DummyFragment{45d7d1a0 #2 id=0x7f0a0004} 01-07 19:00:18.523: V/MyFragmentActivity(4124): onStart DummyFragment{45d7d1a0 #2 id=0x7f0a0004} 01-07 19:00:18.543: V/FriendListFragment(4124): onActivityCreated FriendListFragment{45e4a7f8 #0 id=0x7f0a0002} 01-07 19:00:18.548: V/DummyFragment(4124): onCreateView DummyFragment{45d7d1a0 #2 id=0x7f0a0004} 01-07 19:00:18.548: V/DummyFragment(4124): onActivityCreated DummyFragment{45d7d1a0 #2 id=0x7f0a0004} 01-07 19:00:18.548: V/FriendListFragment(4124): onLoadFinished FragmentManager{45d8e478 in MyFragmentActivity{45e4a6d8}} 01-07 19:00:18.548: V/FriendListFragment(4124): onLoadFinished FriendListFragment{45e4a7f8 #0 id=0x7f0a0002} 01-07 19:00:18.553: V/DummyFragment(4124): onStart DummyFragment{45d7d1a0 #2 id=0x7f0a0004} 01-07 19:00:18.553: V/FriendListFragment(4124): onLoadFinished FragmentManager{45d8e478 in MyFragmentActivity{45e4a6d8}} 01-07 19:00:18.553: V/FriendListFragment(4124): onLoadFinished FriendListFragment{45e4a7f8 #0 id=0x7f0a0002} 01-07 19:00:18.558: V/MyFragmentActivity(4124): onResume DummyFragment{45d7d1a0 #2 id=0x7f0a0004} 01-07 19:00:18.558: V/MyFragmentActivity(4124): onPostResume DummyFragment{45d7d1a0 #2 id=0x7f0a0004} 01-07 19:00:18.558: V/MyFragmentActivity(4124): onResumeFragments DummyFragment{45d7d1a0 #2 id=0x7f0a0004} 01-07 19:00:18.558: V/FriendListFragment(4124): onResume FriendListFragment{45e4a7f8 #0 id=0x7f0a0002} 01-07 19:00:18.563: V/FriendListFragment(4124): onCreateLoader FriendListFragment{45e4a7f8 #0 id=0x7f0a0002} 01-07 19:00:18.563: V/DummyFragment(4124): onResume DummyFragment{45d7d1a0 #2 id=0x7f0a0004} 01-07 19:00:18.723: V/FriendListFragment(4124): onLoadFinished FragmentManager{45d8e478 in MyFragmentActivity{45e4a6d8}} 01-07 19:00:18.723: V/FriendListFragment(4124): onLoadFinished FriendListFragment{45e4a7f8 #0 id=0x7f0a0002} 01-07 19:00:18.893: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/onPostExecute FragmentManager{45e384a8 in null}} 01-07 19:00:18.893: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/onPostExecute null 01-07 19:00:18.893: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/onPostExecute null 01-07 19:00:18.923: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/onPostExecute FragmentManager{45e384a8 in null}} 01-07 19:00:18.923: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/onPostExecute null 01-07 19:00:18.923: V/MyFragmentActivity(4124): onFriendAddedAsyncTask/onPostExecute null 01-07 19:00:18.928: D/AndroidRuntime(4124): Shutting down VM 01-07 19:00:18.928: W/dalvikvm(4124): threadid=1: thread exiting with uncaught exception (group=0x4001d7d0) 01-07 19:00:18.938: E/AndroidRuntime(4124): FATAL EXCEPTION: main 01-07 19:00:18.938: E/AndroidRuntime(4124): java.lang.IllegalStateException: Activity has been destroyed 01-07 19:00:18.938: E/AndroidRuntime(4124): at android.support.v4.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1329) 01-07 19:00:18.938: E/AndroidRuntime(4124): at android.support.v4.app.BackStackRecord.commitInternal(BackStackRecord.java:548) 01-07 19:00:18.938: E/AndroidRuntime(4124): at android.support.v4.app.BackStackRecord.commitAllowingStateLoss(BackStackRecord.java:536) 01-07 19:00:18.938: E/AndroidRuntime(4124): at com.xyz.dummy.MyFragmentActivity$onFriendAddedAsyncTask$2.run(MyFragmentActivity.java:476) 01-07 19:00:18.938: E/AndroidRuntime(4124): at android.os.Handler.handleCallback(Handler.java:587) 01-07 19:00:18.938: E/AndroidRuntime(4124): at android.os.Handler.dispatchMessage(Handler.java:92) 01-07 19:00:18.938: E/AndroidRuntime(4124): at android.os.Looper.loop(Looper.java:123) 01-07 19:00:18.938: E/AndroidRuntime(4124): at android.app.ActivityThread.main(ActivityThread.java:4627) 01-07 19:00:18.938: E/AndroidRuntime(4124): at java.lang.reflect.Method.invokeNative(Native Method) 01-07 19:00:18.938: E/AndroidRuntime(4124): at java.lang.reflect.Method.invoke(Method.java:521) 01-07 19:00:18.938: E/AndroidRuntime(4124): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858) 01-07 19:00:18.938: E/AndroidRuntime(4124): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 01-07 19:00:18.938: E/AndroidRuntime(4124): at dalvik.system.NativeStart.main(Native Method)
In onPreExecute() the FriendListFragment has the id=0x7f0a0002. Inside the handler the DummyFragment is created with id=0x7f0a0004. In onPostExecute() both IDs are null. In onPreExecute() the address of MyFragmentActivity is 45e38358. but in onPostExecute() it's null. But in both methods the FragmentManager address is 45e384a8. I guess onPostExecute uses an invalid FragmentManager. But why?
-
samo over 11 yearsIt doesn't help. Behaviour is the same like before.
-
Lisa Anne over 11 years@samo please have you been able to solve the issue? I have a very similar situation link
-
samo over 11 yearsNo, I'm still searching for a solution
-
Oleg Vaskevich over 11 yearsThe reason is that you are leaking your
Activity
because you're keeping a reference to theFragmentManager
. Try my edit above which should require theFragmentManager
and make sure to setfm
when yourActivity
is destroyed. -
samo over 11 yearsAlso with the handler it doesn't work. I guess it's because getSupportFragmentManager() returns the old, but invalid reference. Please see above for details.
-
samo over 11 yearsHow do you keep the reference up-to-date? Do you use additional attach/detach methods to update the reference?
-
Oleg Vaskevich over 11 yearsConsider this code:
private static WeakReference<FragmentActivity> mActivity = null;
-
Oleg Vaskevich over 11 yearsIn a nutshell
WeakReference
prevents you from leaking the activity... you need to callmActivity.get()
to actually get the instance, and it will be null if the activity was destroyed. To update it, you will need to writemActivity = new WeakReference<FragmentActivity>(this);
- a good place is inonCreate()
- which will update the reference. -
Alex Lockwood almost 11 yearsFor those of you who are still searching for a solution... see this blog post about this topic for more information.
-
albertosh over 10 yearsExcelent Blog Post @AlexLockwood! That fixed my problem while educating me :). Thanks!
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Jimmy Ilenloa over 10 yearsthe weak reference idea is indeed a very smart one, this would allow the object be easily garbage collected when necessary. thumbs up samo!
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Harsh almost 9 yearsThanks man, you are a hero for me... nothing worked only your answer. keep up the good work
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wendigo over 7 yearsThanks. This works for me, but I know that isn't the best solution.
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vm345 about 7 yearscan anyone help me in stackoverflow.com/questions/43617600/…
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Bharath almost 7 yearsWhy static is used here ? What if I use
MyFragmentActivity mActivity = this ?
With out static & WeakReference -
Juan Mendez over 6 yearsremoving super method, also disables saving your fragment states.
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Deepak Ganachari over 6 yearsThanks a lot.it was generating a exception, this solution worked well..
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Wijay Sharma about 6 yearsGreat. It solved my problem. But could anyone please explain how?
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breakline almost 6 yearsStatic reference is pretty bad engineering, you should rather tie your asynchtask to the lifecycle and cancel when its necessary
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Irshad Kumail almost 6 years@WijaySharma I suggest you to read this to understand Activity states better - androidclarified.wordpress.com/2018/06/13/…
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Rohit Nishad over 3 yearsi am unable to find
onSaveInstanceState
method. where is this? in my fragment? what is the super class of it. -
rtsketo almost 3 yearsI did something similar, but I used lifecycle and execute the transaction only if it's at least resumed. In emulator works fine, but on a real device it crashes. Why did you use lifecycle in your example?
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Farid over 2 yearsA weak reference is still a dumb idea. The weak reference naming misleads a lot of people. Just to be clear; if there is a reference to a weak reference object your view will still leak even if the view is destroyed
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Farid over 2 years@IrshadKumail This has nothing to do with activity lifecycles. This can happen when you try to pop a fragment when there is another fragment added to the same fragment manager that hosts the fragment you want to pop.