title: Android findViewHolderForAdapterPostion returns null
body: <p>I want to get Viewholder of first completely visible item of my RecyclerView with this code : </p>
  
  <pre><code>myRecyclerView = (RecyclerView) findViewById(R.id.recycler_demo);
  myRecyclerView.setHasFixedSize(true);
  myLayoutManager = new LinearLayoutManager(getApplicationContext())
  myRecyclerView.setLayoutManager(myLayoutManager);
  LinearCardListAdapter myAdapter = new LinearCardListAdapter(getApplicationContext(), initilizeData());
  myRecyclerView.setAdapter(myAdapter);
  ImageView iv = new ImageView(this);
  int adapterPosition = myLayoutManager.findFirstCompletelyVisibleItemPosition();
  RecyclerView.ViewHolder visibleViewHolder = myRecyclerView.findViewHolderForAdapterPosition(adapterPosition);
  </code></pre>
  
  <p>In this case <code>visibleViewHolder</code> is null.</p>
  
  <p>also I tried <code>findViewHolderForAdapterPosition</code> with numbers from 0 to 7 (my dataset is from 0 to 7 with 8 data ) and again I got null;</p>
  
  <p>any solution ?</p>