Caused by: java.lang.IllegalStateException: Fragment already added

Question

My MainActivity's onStart() throws IllegalStateException with 'Fragment Already Added' message. What am i doing wrong?

public class MainActivity extends FragmentActivity implements ServiceConnection {

    @Override
    protected void onStart() {
        super.onStart();
    }
}

Following is exception stacktrace:

java.lang.RuntimeException: 
Unable to start activity ComponentInfo{com.xxx/com.xxx.MainActivity}:
java.lang.IllegalStateException: Fragment already added: cj{38f8de4c #0 id=0x7f0b0079 cj}
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3190)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3300)
    at android.app.ActivityThread.access$1000(ActivityThread.java:211)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1705)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:145)
    at android.app.ActivityThread.main(ActivityThread.java:6946)
    at java.lang.reflect.Method.invoke(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:372)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)
    Caused by: java.lang.IllegalStateException: Fragment already added: cj{38f8de4c #0 id=0x7f0b0079 cj}
    at android.support.v4.app.FragmentManagerImpl.addFragment(FragmentManager.java:1366)
    at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:734)
    at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1682)
    at android.support.v4.app.FragmentController.execPendingActions(FragmentController.java:388)
    at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:607)
    at com.xxx.MainActivity.onStart(MainActivity.java:692)
    at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1264)
    at android.app.Activity.performStart(Activity.java:6613)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3153)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3300) 
    at android.app.ActivityThread.access$1000(ActivityThread.java:211) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1705) 
    at android.os.Handler.dispatchMessage(Handler.java:102) 
    at android.os.Looper.loop(Looper.java:145) 
    at android.app.ActivityThread.main(ActivityThread.java:6946) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at java.lang.reflect.Method.invoke(Method.java:372) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)

please add some more explanation of the problem and what you are trying to achieve — SepJaPro2.4, Dec 12 '16 at 08:29
error says that your fragment is added twice. You shouldn't do that obviously. — Vladyslav Matviienko, Dec 12 '16 at 08:35

Reena · Answer 1 · 2016-12-20T06:27:08.630

You need check if fragment is already exists in transaction or not before replacing or adding fragment to transaction, you can take help from following code:

      public void setFragmentToContainer(Fragment fragment)
        {
            final String tag = fragment.getClass().getName();
            if (manager == null) {
                manager = getSupportFragmentManager();
            }
            if (isFragmentInBackstack(manager,tag)) {
                // Fragment exists, go back to that fragment
                //// you can also use POP_BACK_STACK_INCLUSIVE flag, depending on flow
                manager.popBackStackImmediate(tag, 0);

            } else {
                // Fragment doesn't exist
                // STEP 1 + additional backstack management
            }

            transaction = manager.beginTransaction();
            transaction.replace(R.id.layout_content, fragment);
            if(fragment instanceof CompanyLevelFragment)
            {
                //Exit app on back press
            }else {
                transaction.addToBackStack(tag);
            }
            transaction.commit();


        }

// isFragmentInBackstack method

  public static boolean isFragmentInBackstack(final FragmentManager fragmentManager, final String fragmentTagName) {
        for (int entry = 0; entry < fragmentManager.getBackStackEntryCount(); entry++) {
            if (fragmentTagName.equals(fragmentManager.getBackStackEntryAt(entry).getName())) {
                return true;
            }
        }
        return false;
    }

Yes This method will allow you to keep specific fragments on backstack , This method will check if fragment is already added in Fragment then do popbackstackimmediate with the help of given tag. You have to handle backstack then your problem will get automatically solved — Reena, Dec 13 '16 at 07:34
Why not using `findFragmentByTag()` instead of `isFragmentInBackstack()`? — CoolMind, Mar 01 '19 at 16:09

score 2 · Answer 2 · edited Dec 12 '16 at 08:56

Method replace fragment

public boolean replaceFragment(Fragment fragment) {
        String loadingFragment = fragment.getClass().getName();
        if (fragment.getArguments() != null && fragment.getArguments().containsKey(Constant.FRAGMENT_ID)) {
            loadingFragment += fragment.getArguments().getString(Constant.FRAGMENT_ID);
        }
        FragmentManager fragmentManager = MainActivity.getInstance().getSupportFragmentManager();
        Fragment existedFragment = fragmentManager.findFragmentByTag(loadingFragment);

        if (existedFragment != null) {
            if(getSupportFragmentManager().getBackStackEntryCount() == 1 || existedFragment.isAdded()) {
                return false;
            }
        }

        try {
            fragmentManager.popBackStack(null, FragmentManager.POP_BACK_STACK_INCLUSIVE);
            FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
            fragmentTransaction.replace(R.id.content_fragment, fragment, loadingFragment);
            fragmentTransaction.addToBackStack(loadingFragment);
            //Add fix bug java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState

            if(!isFinishing()) {
                fragmentTransaction.commitAllowingStateLoss();
            }
            else {
                fragmentTransaction.commit();
            }
        }
        catch (IllegalStateException ignored) {
            LogHelper.d(TAG, "IllegalStateException ignored ", ignored.getMessage());
        }
        return true;
    }

fragment.getClass().getName() something return "cj" It is not my desired results — NPBA, Dec 12 '16 at 09:01
Why do you add with `commit()` in a branch `isFinishing()`? I mean, in `if(!isFinishing()) {` you call `commitAllowingStateLoss()`, but in `else` branch call `commit()`. If I don't mind, that will lead to `Can not perform this action after onSaveInstanceState`. — CoolMind, Mar 01 '19 at 15:54

score 2 · Answer 3 · answered Apr 28 '20 at 05:55

2

You can do a quick check:

    if(myFragment.isAdded()){
       return;
    }
// else continue with code

answered Apr 28 '20 at 05:55

Mr T

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score 1 · Answer 4 · answered Aug 10 '17 at 07:19

i used Reena solution but i modified it for backstacks as sometimes you do not want to the current fragment to the back stack. Reena gave a good solution it should have more votes.

public void setFragmentToContainer(Fragment fragment,boolean adddToBackStack)
{
    final String tag = fragment.getClass().getName();

    FragmentManager manager = getSupportFragmentManager();

    if (isFragmentInBackstack(manager,tag)) {
        // Fragment exists, go back to that fragment
        manager.popBackStackImmediate(tag, 0);

    } else {
        // Fragment doesn't exist

        FragmentTransaction transaction = manager.beginTransaction();
        transaction.replace(R.id.fl_cart_detail_host_layout, fragment);
       if(adddToBackStack) transaction.addToBackStack(tag);
        transaction.commit();
    }

}

Why not using `findFragmentByTag()` instead of `isFragmentInBackstack()`? — CoolMind, Mar 01 '19 at 16:10
As I understood you, you don't want to add a fragment if you already have it. Instead you remove upper fragments. — CoolMind, Mar 01 '19 at 16:15

Caused by: java.lang.IllegalStateException: Fragment already added

4 Answers4

Method replace fragment

Linked