Wsrtjtyk

I have looked at many solutions and have made adjustments based on feedback from a previous version of the code I had but i still cant seem to get it to work and have the same error

JudgeActivty:

@Override

protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_judge);



    RecyclerView = (RecyclerView) findViewById(R.id.recycler_view);

    RecyclerView.setHasFixedSize(true);

    RecyclerView.setLayoutManager(new LinearLayoutManager(this));



    ProgressCircle = findViewById(R.id.progress_circle);



    mUploads = new ArrayList<>();



    DatabaseRef = FirebaseDatabase.getInstance().getReference("uploads");



    DatabaseRef.addValueEventListener(new ValueEventListener() {



        @Override

        public void onDataChange(DataSnapshot dataSnapshot) {

            for (DataSnapshot postSnapshot : dataSnapshot.getChildren()) {

                UploadClass upload =

                        postSnapshot.getValue(UploadClass.class);

                mUploads.add(upload);

            }

            Adapter = new ImageAdapter(JudgeActivity.this, mUploads);

            ProgressCircle.setVisibility(View.INVISIBLE);

            RecyclerView.setAdapter(Adapter);

        }

    });

}

Adapter:

public class ImageAdapter extends

        RecyclerView.Adapter<ImageAdapter.ImageViewHolder> {

    private Context mContext;

    private List<UploadClass> mUploads;



    public ImageAdapter(Context context, List<UploadClass> uploads) {

        mContext = context;

        mUploads = uploads;

    }





    @Override

    public ImageViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        View v = LayoutInflater.from(mContext).inflate(R.layout.image_item,

                parent, false);

        return new ImageViewHolder(v);

    }



    @Override

    public void onBindViewHolder(ImageViewHolder holder, int position) {

        UploadClass uploadCurrent = mUploads.get(position);

        holder.textViewName.setText(uploadCurrent.getName());

        Picasso.with(mContext)

                .load(uploadCurrent.getImageUrl())

                .placeholder(R.mipmap.ic_launcher)

                .fit()

                .centerCrop()

                .into(holder.imageView);



    }





    @Override

    public int getItemCount() {

        return mUploads.size();

    }



    public class ImageViewHolder extends RecyclerView.ViewHolder {

        public TextView textViewName;

        public ImageView imageView;



        public ImageViewHolder(View itemView) {

            super(itemView);



            textViewName = itemView.findViewById(R.id.text_view_name);

            imageView = itemView.findViewById(R.id.image_view_upload);

        }

    }



}

Is there actually a problem? That "error" isn't an error, it's just a warning. And it's shown because, when the Activity is first displayed, the RecyclerView has no Adapter set to it. You only set the Adapter when a Firebase value changes, which is a bad idea.

You should create and set the Adapter outside of the ValueEventListener:

RecyclerView = (RecyclerView) findViewById(R.id.recycler_view);

RecyclerView.setHasFixedSize(true);

RecyclerView.setLayoutManager(new LinearLayoutManager(this));

Adapter = new ImageAdapter(JudgeActivity.this, mUploads);

RecyclerView.setAdapter(Adapter);

Also, in Java, variable names follow camelCase, not TitleCase. You don't have to follow that guideline, but it makes it less confusing for others when debugging your code.