Problem setting ListView selector color when pressed

Question

I have the following ListView, and have followed the answer from this SO Question w/ no luck:

http://stackoverflow.com/questions/2038040/android-listview-selector-color

<ListView android:layout_width="fill_parent"
            android:layout_height="fill_parent" xmlns:android="http://schemas.android.com/apk/res/android"
            android:id="@+id/ARListView" 
            android:background="@drawable/transparent_background" 
            android:cacheColorHint="#00000000" 
            android:listSelector="@drawable/ar_selector" 
            android:drawSelectorOnTop="true">

Here is my ar_selector.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android"&gt;
  <item android:state_enabled="false" android:state_focused="true"
        android:drawable="@android:color/transparent" />
  <item android:state_pressed="true"
        android:drawable="@color/solid_red" />
  <item android:state_focused="true"
        android:drawable="@android:color/transparent" />
</selector>

When I press down on a ListViewItem nothing appears.