Uruchamianie okna dialogowego z innego fragmentu: IllegalStateException: Nie można wykonać tej akcji po parametrze onSaveInstanceState

Question

Tak więc próbuję zrozumieć, jak rozwiązać ten problem, ale nie mogę go naprawiać. W tej chwili mam jeden fragment z jednym przyciskiem. Po naciśnięciu tego przycisku uruchomi się niestandardowy DialogFragment za pomocą przycisków ok/cancel.

Jeśli naciśniesz przycisk OK, uruchomi się kolejny niestandardowy DialogFragment, tym razem jest to fragment ProgressDialog. Problem polega na tym, że gdy pojawia się okno dialogowe ok/anulowania, gdy się obracam, a następnie naciśnij przycisk ok, a następnie wywołaj fragment ProgressDialog otrzymuję ten błąd. Jeśli obracam tylko podczas wyświetlania fragmentu progressdialog, nie ma problemu. Korzystam z pakietu pomocy v4. Oto klas:

główną działalność:

public class MainActivity extends FragmentActivity implements OnFragmentAttachedListener, Callbacks{ 

boolean mResumed = false; 

@Override 
public void onCreate(Bundle savedInstanceState) 
{ 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    FragmentManager fragmentManager = getSupportFragmentManager(); 
    FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction(); 

    fragmentTransaction.add(R.id.main_id, new EmptyFragmentWithCallbackOnResume()); 
    fragmentTransaction.commitAllowingStateLoss(); 

} 
@Override 
public void onTaskFinished() 
{ 
    // Hooray. A toast to our success. 
    Toast.makeText(this, "Task finished!", Toast.LENGTH_LONG).show(); 
    // NB: I'm going to blow your mind again: the "int duration" parameter of makeText *isn't* 
    // the duration in milliseconds. ANDROID Y U NO ENUM? 
} 

@Override 
public void OnFragmentAttached() { 

} } 

okcancel dialogfragment:

public class OkCancelDialogFragment<T> extends DialogFragment { 

public final static String TITLE="title"; 

private OkCancelDialogEvents<T> buttonEvents; 
private T[] params; 


public OkCancelDialogFragment(String title, OkCancelDialogEvents<T> buttonEvents, T... params) { 

    this.buttonEvents=buttonEvents; 

    Bundle args = new Bundle(); 
    args.putString(TITLE, title); 
    this.setArguments(args); 

    this.params=params; 

} 


@Override 
public void onCreate(Bundle savedInstanceState) { 
    // TODO Auto-generated method stub 
    super.onCreate(savedInstanceState); 
    this.setRetainInstance(true); 
} 


@Override 
public void onDestroyView() { 
    if (getDialog() != null && getRetainInstance()) 
    getDialog().setDismissMessage(null); 
    super.onDestroyView(); 
} 


@Override 
public Dialog onCreateDialog(Bundle savedInstanceState) { 

    String title = getArguments().getString(TITLE); 
    return new AlertDialog.Builder(getActivity()) 
    //.setIcon(R.drawable.alert_dialog_icon) 
    .setTitle(title) 
    .setPositiveButton("ok", 
     new DialogInterface.OnClickListener() { 
      public void onClick(DialogInterface dialog, int whichButton) { 
       buttonEvents.onPositiveClick(params); 
      } 
     } 
    ) 
    .setNegativeButton("cancel", 
     new DialogInterface.OnClickListener() { 
      public void onClick(DialogInterface dialog, int whichButton) { 
       buttonEvents.onNegativeClick(); 
      } 
     } 
    ) 
    .create(); }} 

postęp fragment dialogowe:

public class TaskFragment extends DialogFragment{ 
// The task we are running. 
GenericTask<?,?> mTask; 
ProgressDialog mProgressDialog; 
String title, message; 

public void setTask(MyTask task) 
{ 
    mTask = task; 

    // TellsetFragment the AsyncTask to call updateProgress() and taskFinished() on this fragment. 

    mTask.setFragment(this); 
} 


public void setTitleMessage(String title, String message){ 
    this.title=title; 
    this.message=message;  
} 


@Override 
public void onCreate(Bundle savedInstanceState) 
{ 
    super.onCreate(savedInstanceState); 

    // Retain this instance so it isn't destroyed when MainActivity and 
    // MainFragment change configuration. 
    setRetainInstance(true); 

} 

@Override 
public Dialog onCreateDialog(Bundle savedInstanceState) { 

    mProgressDialog= new ProgressDialog(getActivity()); 
    mProgressDialog.setTitle(title); 
    mProgressDialog.setMessage(message); 
    mProgressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL); 
    mProgressDialog.setCanceledOnTouchOutside(false); 

    return mProgressDialog; 
} 

// This is to work around what is apparently a bug. If you don't have it 
// here the dialog will be dismissed on rotation, so tell it not to dismiss. 
@Override 
public void onDestroyView() 
{ 
    if (getDialog() != null && getRetainInstance()) 
     getDialog().setDismissMessage(null); 
    super.onDestroyView(); 
} 

// Also when we are dismissed we need to cancel the task. 
@Override 
public void onDismiss(DialogInterface dialog) 
{ 
    super.onDismiss(dialog); 
    // If true, the thread is interrupted immediately, which may do bad things. 
    // If false, it guarantees a result is never returned (onPostExecute() isn't called) 
    // but you have to repeatedly call isCancelled() in your doInBackground() 
    // function to check if it should exit. For some tasks that might not be feasible. 
    if (mTask != null) 
     mTask.cancel(false); 

    // You don't really need this if you don't want. 
    if (getTargetFragment() != null) 
     getTargetFragment().onActivityResult(MainFragment.TASK_FRAGMENT, Activity.RESULT_CANCELED, null); 
} 

@Override 
public void onResume() 
{ 
    super.onResume(); 
    // This is a little hacky, but we will see if the task has finished while we weren't 
    // in this activity, and then we can dismiss ourselves. 
    if (mTask == null) 
     dismiss(); 
} 

// This is called by the AsyncTask. 
public void updateProgress(int percent) 
{ 
    mProgressDialog.setProgress(percent); 
} 

// This is also called by the AsyncTask. 
public void taskFinished() 
{ 
    // Make sure we check if it is resumed because we will crash if trying to dismiss the dialog 
    // after the user has switched to another app. 
    if (isResumed()) 
     dismiss(); 

    // If we aren't resumed, setting the task to null will allow us to dimiss ourselves in 
    // onResume(). 
    mTask = null; 

    // Tell the fragment that we are done. 
    if (getTargetFragment() != null) 
     getTargetFragment().onActivityResult(MainFragment.TASK_FRAGMENT, Activity.RESULT_OK, null); 
} 

}

mainFragment:

public class MainFragment extends Fragment implements OkCancelDialogEvents<Void>, OnClickListener{ 
// This code up to onDetach() is all to get easy callbacks to the Activity. 
private Callbacks mCallbacks = sDummyCallbacks; 

private static Callbacks sDummyCallbacks = new Callbacks() 
{ 
    public void onTaskFinished() { } 
}; 

@Override 
public void onAttach(Activity activity) 
{ 
    super.onAttach(activity); 
    if (!(activity instanceof Callbacks)) 
    { 
     throw new IllegalStateException("Activity must implement fragment's callbacks."); 
    } 
    mCallbacks = (Callbacks) activity; 
} 

@Override 
public void onDetach() 
{ 
    super.onDetach(); 
    mCallbacks = sDummyCallbacks; 
} 

// Save a reference to the fragment manager. This is initialised in onCreate(). 
private FragmentManager mFM; 

// Code to identify the fragment that is calling onActivityResult(). We don't really need 
// this since we only have one fragment to deal with. 
static final int TASK_FRAGMENT = 0; 

// Tag so we can find the task fragment again, in another instance of this fragment after rotation. 
static final String TASK_FRAGMENT_TAG = "task"; 

@Override 
public void onCreate(Bundle savedInstanceState) 
{ 
    //this.setRetainInstance(true); 
    super.onCreate(savedInstanceState); 
    // At this point the fragment may have been recreated due to a rotation, 
    // and there may be a TaskFragment lying around. So see if we can find it. 
    mFM = getFragmentManager(); 
    // Check to see if we have retained the worker fragment. 
    TaskFragment taskFragment = (TaskFragment)mFM.findFragmentByTag(TASK_FRAGMENT_TAG); 

    if (taskFragment != null) 
    { 
     // Update the target fragment so it goes to this fragment instead of the old one. 
     // This will also allow the GC to reclaim the old MainFragment, which the TaskFragment 
     // keeps a reference to. Note that I looked in the code and setTargetFragment() doesn't 
     // use weak references. To be sure you aren't leaking, you may wish to make your own 
     // setTargetFragment() which does. 
     taskFragment.setTargetFragment(this, TASK_FRAGMENT); 
    } 

} 

@Override 
public View onCreateView(LayoutInflater inflater, ViewGroup container, 
     Bundle savedInstanceState) 
{ 
    return inflater.inflate(R.layout.fragment_main, container, false); 
} 

@Override 
public void onActivityCreated(Bundle savedInstanceState) { 

    super.onActivityCreated(savedInstanceState); 
    if(savedInstanceState!=null) 
     Toast.makeText(getActivity(), savedInstanceState.getString("documents"), Toast.LENGTH_SHORT).show(); 
} 

@Override 
public void onSaveInstanceState(Bundle outState) { 

    super.onSaveInstanceState(outState); 
    outState.putString("documents", "teste"); 
} 

@Override 
public void onViewCreated(View view, Bundle savedInstanceState) 
{ 
    super.onViewCreated(view, savedInstanceState); 

    // Callback for the "start task" button. I originally used the XML onClick() 
    // but it goes to the Activity instead. 
    view.findViewById(R.id.taskButton).setOnClickListener(this); 
} 

@Override 
public void onClick(View v) 
{ 

    OkCancelDialogFragment<Void> dialog = new OkCancelDialogFragment<Void>("Teste", this); 
    dialog.setTargetFragment(this, 2); 
    dialog.show(getFragmentManager(), "basic_dialog"); 


} 

@Override 
public void onActivityResult(int requestCode, int resultCode, Intent data) 
{ 
    if (requestCode == TASK_FRAGMENT && resultCode == Activity.RESULT_OK) 
    { 
     // Inform the activity. 
     mCallbacks.onTaskFinished(); 
    } 
} 


@Override 
public void onPositiveClick(Void... params) { 

    // We only have one click listener so we know it is the "Start Task" button. 

    // We will create a new TaskFragment. 
    TaskFragment taskFragment = new TaskFragment(); 
    // And create a task for it to monitor. In this implementation the taskFragment 
    // executes the task, but you could change it so that it is started here. 

    MyTask task=new MyTask(); 
    task.execute("one","two"); 

    taskFragment.setTask(task); 
    taskFragment.setTitleMessage("File Download", "Downloading..."); 
    // And tell it to call onActivityResult() on this fragment. 
    taskFragment.setTargetFragment(this, TASK_FRAGMENT); 
    // Show the fragment. 
    // I'm not sure which of the following two lines is best to use but this one works well. 
    taskFragment.show(mFM, TASK_FRAGMENT_TAG); 
    //mFM.beginTransaction().add(taskFragment, TASK_FRAGMENT_TAG).commit(); 

} 

@Override 
public void onNegativeClick() { 


}} 

Oto błędy:

12-12 11:24:52.144: E/AndroidRuntime(2451): FATAL EXCEPTION: main 
12-12 11:24:52.144: E/AndroidRuntime(2451): java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at android.support.v4.app.FragmentManagerImpl.checkStateLoss(FragmentManager.java:1327) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at android.support.v4.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1338) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at android.support.v4.app.BackStackRecord.commitInternal(BackStackRecord.java:595) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at android.support.v4.app.BackStackRecord.commit(BackStackRecord.java:574) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at android.support.v4.app.DialogFragment.show(DialogFragment.java:127) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at com.example.progressdialog.MainFragment.onPositiveClick(MainFragment.java:149) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at com.example.progressdialog.MainFragment.onPositiveClick(MainFragment.java:1) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at com.example.progressdialog.OkCancelDialogFragment$1.onClick(OkCancelDialogFragment.java:56) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at com.android.internal.app.AlertController$ButtonHandler.handleMessage(AlertController.java:196) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at android.os.Handler.dispatchMessage(Handler.java:99) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at android.os.Looper.loop(Looper.java:123) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at android.app.ActivityThread.main(ActivityThread.java:4627) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at java.lang.reflect.Method.invokeNative(Native Method) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at java.lang.reflect.Method.invoke(Method.java:521) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 
12-12 11:24:52.144: E/AndroidRuntime(2451):  at dalvik.system.NativeStart.main(Native Method) 

Answer 1

To wydaje się być błąd z pakietu zgodności (który nie został jeszcze rozwiązany). W każdym razie można uniknąć tego błędu, modyfikując kod, aby lepiej obsługiwać komunikację między fragmentami. Zmodyfikowałem Twój przykładowy projekt (który można znaleźć pod adresem here). W związku z tym nie wiem, jak prosty jest twój przykład, ale jeśli wszystkie wywołania zwrotne wskazują na działanie, powinieneś pozwolić klasie aktywności obsługiwać fragmenty (na przykład uruchamiać okna dialogowe) i komunikację między nimi, ponieważ " widzi "i zna stan wszystkich zawartych w nim fragmentów.