title: add space to top and bottom of ListView so top and bottom item can be centered
body: <p>My ListView items need to be centered when they are selected, but the top and bottom items stop at the top or bottom of the list. How do I center the top and bottom items?</p>
  
  <p>Here's my test layout:</p>
  
  <pre><code>    &lt;RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
         android:id="@+id/parent"
         android:layout_width="fill_parent"
         android:layout_height="fill_parent"
         android:clipChildren="false"
         android:clipToPadding="false"
         android:gravity="top" &gt;
  
         &lt;ListView
             android:id="@+id/listview"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_centerVertical="true"
            android:clipChildren="false"
            android:clipToPadding="false" &gt;
         &lt;/ListView&gt;
  
      &lt;/RelativeLayout&gt;
  </code></pre>