Add a new item to recyclerview programmatically?

Shubham Kanodia picture Shubham Kanodia · Jan 8, 2015 · Viewed 137.7k times · Source

I'm still trying to get my head around recyclerview. I have an arraylist, that I use to initialize a recycler view with.

How can I add new items to the recycler view post setting an adapter and layoutmanager?

private void initData() {
        mItems = new ArrayList<String>();
        for (int i = 0; i < ITEMS_COUNT; i++) {
            mItems.add("Item " + (i + 1));
        }
    }

    private void initRecyclerView() {
        mRecentRecyclerView = (RecyclerView) findViewById(R.id.recentrecyclerView);
        mRecentRecyclerView.setHasFixedSize(true);
        mRecentLayoutManager = new LinearLayoutManager(this);
        mRecentRecyclerView.setLayoutManager(mRecentLayoutManager);



        mAdapter = new RecyclerView.Adapter<CustomViewHolder>() {
            @Override
            public CustomViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
                View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.notice_snippet
                        , viewGroup, false);
                return new CustomViewHolder(view);
            }

            @Override
            public void onBindViewHolder(CustomViewHolder viewHolder, int i) {
                viewHolder.noticeSubject.setText(mItems.get(i));
            }

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

        };
        mRecentRecyclerView.setAdapter(mAdapter);

    private class CustomViewHolder extends RecyclerView.ViewHolder {

        private TextView noticeSubject;

        public CustomViewHolder(View itemView) {
            super(itemView);

            noticeSubject = (TextView) itemView.findViewById(R.id.notice_subject);
        }
    }

So basically after I initdata() and initRecyclerView(), how do i add a new item to the RecyclerView??

Answer

Mostafa picture Mostafa · Apr 5, 2015

First add your item to mItems and then use:

mAdapter.notifyItemInserted(mItems.size() - 1);

this method is better than using:

mAdapter.notifyDataSetChanged();

in performance.