Ich verwende die Support-Bibliothek für meine App. In meiner FragmentActivity verwende ich eine AsyncTask zum Herunterladen von Daten aus dem Internet. In der onPreExecute () -Methode füge ich ein Fragment hinzu und in der onPostExecute () -Methode entferne ich es erneut. Wenn die Ausrichtung dazwischen geändert wird, erhalte ich die oben genannte Ausnahme. Bitte schauen Sie sich die Details an:
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");
...
}
Ich erhalte folgenden 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 anderen Threads zu ähnlichen Problemen scheint der Grund darin zu liegen, dass die onPostExecute-Methode aufgerufen wird, bevor die onResume () -Methode aufgerufen wird. Aber ich bekomme die Ausnahme, obwohl onResume () vorher aufgerufen wurde.
Weiß jemand, was los ist?
Die Aktivität sieht folgendermaßen aus:
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);
}
}
Bei Verwendung von commitAllowingStateLoss () tritt folgende Ausnahme auf:
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)
Ich erhalte dieselbe IllegalStateExeption, wenn ich die AsynTask wie folgt implementiere, da die findFragmentById () -Methode einen Nullzeiger zurückgibt.
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();
}
Im nächsten Schritt verwende ich einen Handler zum Hinzufügen und Entfernen des DummyFragments. Zusätzlich habe ich einige weitere Debug-Ausgaben hinzugefügt.
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();
}
});
Ich erhalte folgenden 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 () hat das FriendListFragment die ID = 0x7f0a0002. Im Handler wird das DummyFragment mit der ID = 0x7f0a0004 erstellt. In onPostExecute () sind beide IDs null. In onPreExecute () lautet die Adresse von MyFragmentActivity 45e38358. aber in onPostExecute () ist es null. Bei beiden Methoden lautet die FragmentManager-Adresse jedoch 45e384a8. Ich denke, onPostExecute verwendet einen ungültigen FragmentManager. Aber wieso?