title: Scrollbar not showing in RecyclerView
body: <p>I've got a <code>RecyclerView</code> and would like to have scrollbar showing, when it covers more than one page.</p>
  
  <p>I get no scrollbar at all. Any idea?</p>
  
  <p>My layout:</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" &gt;
  
      &lt;CheckBox
          android:id="@+id/cl_only_empty"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:elevation="5dp"
          android:text="@string/cl_only_empty"
          android:textColor="@color/white" /&gt;
  
      &lt;android.support.v7.widget.RecyclerView
          android:id="@+id/callsList"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:scrollbars="vertical" /&gt;
  
  &lt;/LinearLayout&gt;
  </code></pre>