title: Android: Cannot style spinner divider
body: <p>I'm trying to create a theme for my first Android app, and it is driving me round the bend. I finally managed to figure out how to style items in a dropdown list, but now I can't change the colour of the divider between list items. I have searched similar questions on stackoverflow, and tried dozens of combinations, but nothing seems to work.</p>
  
  <p>Here is my styles.xml file (abbreviated for clarity):</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;resources&gt;
    &lt;style name="MyTheme" parent="android:Theme.Light"&gt;
      &lt;item name="android:spinnerStyle"&gt;@style/spinnerStyle&lt;/item&gt;
      &lt;item name="android:spinnerDropDownItemStyle"&gt;@style/spinnerDropDownItemStyle&lt;/item&gt;    
      &lt;item name="android:dropDownListViewStyle"&gt;@style/spinnerListViewStyle&lt;/item&gt;
    &lt;/style&gt;
  
    &lt;style name="spinnerStyle" parent="@android:style/Widget.Spinner"&gt;
        &lt;item name="android:background"&gt;@drawable/my_theme_spinner&lt;/item&gt;
    &lt;/style&gt;
  
    &lt;style name="spinnerDropDownItemStyle" parent="@android:style/Widget.DropDownItem.Spinner"&gt;
        &lt;item name="android:background"&gt;@drawable/my_theme_spinner_item&lt;/item&gt;
        &lt;item name="android:paddingLeft"&gt;5dp&lt;/item&gt;
        &lt;item name="android:gravity"&gt;center_vertical&lt;/item&gt;
    &lt;/style&gt;
  
    &lt;style name="spinnerListViewStyle" parent="@android:style/Widget.ListView.DropDown"&gt;
        &lt;item name="android:height"&gt;3dp&lt;/item&gt;
        &lt;item name="android:dividerHeight"&gt;3dp&lt;/item&gt;
        &lt;item name="android:divider"&gt;@color/divider&lt;/item&gt;
    &lt;/style&gt;
  &lt;/resources&gt;
  </code></pre>
  
  <p>No matter what I do, I just get a 1dp light grey divider between items (which can barely be seen with my light coloured list item background) - neither the height nor colour of the divider is ever affected (I also tried setting it to a drawable, also with no effect). What am I doing wrong?</p>