26

I'm working with Android's new RecyclerView but I can't get my custom adapter to refresh whenever I call one of the "notify" methods.

I've tried calling notifyDataSetChanged, notifyItemRangeInserted and notifyItemInserted and none of them seem to work.

Here's the code for my custom adapter. I'm basically trying to refresh a list of Strings:

package com.mycompany.myapp.adapters;

import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.LinearLayout;
import android.widget.TextView;

import com.mycompany.myapp.R;

import java.util.List;

public class FeedAdapter extends RecyclerView.Adapter<FeedAdapter.ViewHolder> {

    private List<String> mDataset;

    public FeedAdapter(List<String> dataset) {
        super();
        mDataset = dataset;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int i) {
        LinearLayout v = (LinearLayout) LayoutInflater.from(parent.getContext())
                .inflate(R.layout.list_item_feed, parent, false);
        v.setLayoutParams(new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
                ViewGroup.LayoutParams.WRAP_CONTENT));
    return new ViewHolder(v);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        holder.setText(mDataset.get(position));
    }

    @Override
    public int getItemCount() {
        return mDataset.size();
    }

    public void setDataset(List<Status> dataset) {
        mDataset = dataset;
        // This isn't working
        notifyItemRangeInserted(0, mDataset.size());
    }

    public static class ViewHolder extends RecyclerView.ViewHolder {
        private TextView mFeedText;

        public ViewHolder(View v) {
            super(v);
            mFeedText = (TextView) v.findViewById(R.id.feed_text);
        }

        private void setText(String text) {
            mFeedText.setText(text);
        }
    }
}

Anyone else having this issue?

Thanks!

wmora
  • 1,203
  • 1
  • 9
  • 17

2 Answers2

26

My issue was that I was not notifying the change on the main thread, therefore the change was not visible right away. It is the same issue pointed out here.

Community
  • 1
  • 1
wmora
  • 1,203
  • 1
  • 9
  • 17
11

I was trying to update RecycleView with notifyDataSetChanged() method in response to com.google.common.eventbus.Subscribe.

Like @wmora mentioned the problem was that the notify method was not called in the main UI thread.

I resolved it with AndroidAnnotations' @UiThread

@UiThread
protected void dataSetChanged() {
    notifyDataSetChanged();
}

which is equivalent to:

 final Adapter adapter = this;
 new Handler(Looper.getMainLooper()).post(new Runnable() {
    @Override
    public void run() {
       adapter.notifyDataSetChanged();
    }
 });

note: just separate new Handler into class private field

  • I am facing an issue regarding RecyclerView. When i add item , it doesnt show up in the list. When i rotate the screen, since the page is recreated the newly added item is displayed. What i do is, when i click add button i add the item and call adapter.notifyDataSetChanged(); – prakashpun Sep 29 '15 at 10:12
  • 1
    That annotation is a marker only used for code correctness. It is not equivalent to posting to a handler. – Jeffrey Blattman Oct 24 '19 at 17:11