java.lang.NullPointerException: Error while using RecyclerView.Widget

Question

I am trying to add a list of audio files to my fragment. I have also set the layout manager to recycler view. I have also added dependencies to gradle build

Here is the error:


java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View androidx.recyclerview.widget.RecyclerView.findViewById(int)' on a null object reference
        at com.example.musicplayer.AllSongs.onCreateView(AllSongs.java:35)
        at androidx.fragment.app.Fragment.performCreateView(Fragment.java:2698)

I am trying to get all songs in my all songs fragment. Here is my code which shows error:

    public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        recyclerView = recyclerView.findViewById(R.id.recyclerView);
        recyclerView.setHasFixedSize(true);
        if (!(musicFiles.size() < 1))
        {
            musicAdapter = new MusicAdapter(getContext(),musicFiles);
            recyclerView.setAdapter(musicAdapter);
            recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
        }
        return inflater.inflate(R.layout.fragment_all_songs_tab, container, false);
    }

IntelliJ Amiya · Answer 1 · 2020-07-03T14:03:57.913

2

Try with

 @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_all_songs_tab, container, false);

        recyclerView = view.findViewById(R.id.recyclerView);
        recyclerView.setHasFixedSize(true);
        musicFiles = new ArrayList();
        if (!(musicFiles.size() < 1))
        {
            musicAdapter = new MusicAdapter(getContext(),musicFiles);
            recyclerView.setAdapter(musicAdapter);
            recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
        }

        return view;
    }

edited Jul 03 '20 at 14:03

answered Jul 03 '20 at 13:54

IntelliJ Amiya

74,896
15
165
198

1

i have tried it but " java.lang.NullPointerException: Attempt to invoke virtual method 'int java.util.ArrayList.size()' on a null object reference " this error pops – Mad_Flasher_oo7 Jul 03 '20 at 14:00
1

@Mad_Flasher_oo7 `musicFiles=new ArrayList()`; – IntelliJ Amiya Jul 03 '20 at 14:01
@Mad_Flasher_oo7 You can – IntelliJ Amiya Jul 03 '20 at 14:05
1

thank you so much it worked but its empty logcat shows No adapter attached can you help me with it? – Mad_Flasher_oo7 Jul 03 '20 at 14:07
1

@Mad_Flasher_oo7 https://stackoverflow.com/questions/29141729/recyclerview-no-adapter-attached-skipping-layout – IntelliJ Amiya Jul 03 '20 at 14:08

score 2 · Answer 2 · answered Jul 03 '20 at 13:54

Your app is crash at below line

 recyclerView.findViewById(R.id.recyclerView);

Do as per below

 onCreateView(.....){
 View v = inflater.inflate(R.layout.fragment_all_songs_tab, container, false);
 recyclerView = v.findViewById(R.id.recyclerView);
 ....
 ....
 return v ;
 }

Mad_Flasher_oo7 · Accepted Answer · 2020-07-22T17:32:17.667

0

the error is fixed here is the solution

What I have done:

earlier I was returning onCreateView function but after returning inflater in View my code was fixed and list of audio files was shown


 View view = inflater.inflate(R.layout.fragment_all_songs_tab, container, false);

        recyclerView = view.findViewById(R.id.recyclerView);
        recyclerView.setHasFixedSize(true);

            musicAdapter = new MusicAdapter(getContext(), musicFiles);
            recyclerView.setAdapter(musicAdapter);
            recyclerView.setLayoutManager(new LinearLayoutManager(getContext(), RecyclerView.VERTICAL, false));
        musicAdapter.notifyDataSetChanged();

            return view;

edited Jul 22 '20 at 17:32

answered Jul 22 '20 at 17:18

Mad_Flasher_oo7

65
1
6

Providing blob of code without explanation is quite counter educational. Please provide more info what was the problem – Marcin Orlowski Jul 22 '20 at 17:22
I don't have much knowledge of explaining, but ill try my best to explain what I have done to fix my code – Mad_Flasher_oo7 Jul 22 '20 at 17:27

java.lang.NullPointerException: Error while using RecyclerView.Widget

3 Answers3