title: Error support v4 view.NestedScrollingChild2 in recycleview set adapter
body: <p>I want create a horizontal recycle view and i writed this code:</p>
  
  <p>in main activity xml</p>
  
  <pre><code> &lt;RelativeLayout
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:layout_marginTop="10dp" &gt;
      &lt;android.support.v7.widget.RecyclerView
      android:id="@+id/my_recycler_view"
      android:layout_width="match_parent"
      android:layout_height="match_parent"/&gt;
  &lt;/RelativeLayout&gt;
  </code></pre>
  
  <p>And this is adapter class</p>
  
  <pre><code>public class AdapterNote extends ArrayAdapter&lt;StructCategory&gt; {
  
  public AdapterNote(ArrayList&lt;StructCategory&gt; array) {
      super(G.context, R.layout.adapter_category, array);
  }
  private static class ViewHolder {
  
      public TextView txtTitle;
  
  
      public ViewHolder(View view) {
          txtTitle = (TextView) view.findViewById(R.id.cat_txt);
  
      }
      public void fill(final ArrayAdapter&lt;StructCategory&gt; adapter, final StructCategory item, final int position) {
          txtTitle.setText(item.title);
      }
  }
  @Override
  public View getView(int position, View convertView, ViewGroup parent) {
      ViewHolder holder;
  
      StructCategory item = getItem(position);
      if (convertView == null) {
          convertView = G.inflater.inflate(R.layout.adapter_category, parent, false);
          holder = new ViewHolder(convertView);
          convertView.setTag(holder);
      } else {
          holder = (ViewHolder) convertView.getTag();
      }
  
      holder.fill(this, item, position);
      return convertView;
  }}
  </code></pre>
  
  <p>In the MainClass setadapter
  setadapter function has error : 
  The type android.support.v4.view.NestedScrollingChild2 cannot be resolved. It is indirectly referenced from required .class files</p>
  
  <p>I imported support v4 api 20 and v7compat v20 and v7 recycleview api 20
  but dont work my code</p>
  
  <pre><code>LinearLayoutManager layoutManager = new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false);
  
      RecyclerView myList = (RecyclerView) findViewById(R.id.my_recycler_view);
      myList.setLayoutManager(layoutManager);
      adapter = new AdapterNote(G.tasksCategory);
      myList.setAdapter(adapter);
  </code></pre>
  
  <p>and i create xml for adapter class:</p>
  
  <pre><code>&lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:orientation="vertical" android:padding="8dip" android:gravity="right"&gt;
  &lt;TextView
      android:id="@+id/cat_txt"
      android:layout_width="80dp"
      android:layout_height="80dp"
      android:background="@drawable/category_txt"
      android:gravity="center_vertical|center"
      android:text="TextView"
      android:textColor="#000" /&gt;
      &lt;/LinearLayout&gt;
  </code></pre>
  
  <p>please help me for this problem</p>