选项卡片段错误发生，并且片段父活动已被破坏

Question

Error occurs when switching from one tab to another, the Main Fragment Activity has been destroyed.

My fragment child Profile_album_details code:

case R.id.ib_photo_delete:
        String stringiq = "";
        NewTask.iq = new CustomIQ("<albummanagement xmlns='naseebalbum'           action='deletepicture'><albumname>"+album.getAlbum_name()+"</albumname><picturetitle>"+picture.getTitle()+"</picturetitle></albummanagement>");
        NewTask.iq.setType(IQ.Type.SET);
        new NewTask(context).execute();
        while(NewTask.connection.isAuthenticated() == false){}
        Profile_album_details.pictures.remove(imageno);
        Profile_display_photo.pictures = Profile_album_details.pictures;
        new MainActivity().updateTab(new Profile_album_details(), R.id.tab2,true); 

Main activity parent fragment class:

public void updateTab(Fragment frg,
            int place_holder, boolean addTobackStack) 
    {
        // TODO Auto-generated method stub
        FragmentTransaction ft=getFragmentManager().beginTransaction();

        ft.replace(place_holder, frg);
//      ft.setTransition(transaction);

        if(addTobackStack)
            ft.addToBackStack(null);
            ft.commit();
    }



> 10-02 15:25:55.061: E/AndroidRuntime(1920): FATAL EXCEPTION: main
>     10-02 15:25:55.061: E/AndroidRuntime(1920): java.lang.IllegalStateException: Activity has been destroyed
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at android.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1333)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at android.app.BackStackRecord.commitInternal(BackStackRecord.java:595)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at android.app.BackStackRecord.commit(BackStackRecord.java:574)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at com.example.tabs.MainActivity.updateTab(MainActivity.java:166)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at com.example.tabs.MainActivity.launchNewFragment(MainActivity.java:175)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at adapters.Profile_display_photo.onClick(Profile_display_photo.java:164)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at android.view.View.performClick(View.java:4240)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at android.view.View$PerformClick.run(View.java:17721)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at android.os.Handler.handleCallback(Handler.java:730)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at android.os.Handler.dispatchMessage(Handler.java:92)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at android.os.Looper.loop(Looper.java:137)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at android.app.ActivityThread.main(ActivityThread.java:5103)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at java.lang.reflect.Method.invokeNative(Native Method)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at java.lang.reflect.Method.invoke(Method.java:525)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
>     10-02 15:25:55.061: E/AndroidRuntime(1920):   at dalvik.system.NativeStart.main(Native Method)

Answer 1

I think I understand the question now. FragmentTransaction.commit() is not executed immediately, there is a delay between when the method is called and when the actual transaction commit is executed. That's the reason why when you call the FragmentTransaction.commit() and then finish() the Activity you get that error, because the Activity is destroyed before the transaction commit is executed.

To avoid this use FragmentManager.executePendingTransactions() . This should, as the name indicates, execute all the pending transactions immediately. Without seeing your whole code I would guess that the best place is before the Activity.finish() call, but if that doesn't work then try after the commit()