title: Why my android spinner is transparent?
body: <p>I'm an Android newbie...
  And I have a problem with my spinners.
  I have an activity with an image as background and a spinner with items (a list of years) loaded by code using an adapter.
  The problem is that when the spinner is closed, it's transparent except of the text and the right down corner triangle (black).
  If I set the spinner background color, the right down corner disappear and the spinner becomes very similar to a textView (too much confused for the user!).</p>
  
  <p>If I change the activity style (for example "Black"), in the graphical view the spinner becomes like I want it:
  lightgray and with the right down corner.</p>
  
  <p>But in the runtime phase, it becomes again transparent.</p>
  
  <p><a href="http://www.flickr.com/photos/27924376@N06/8624765886/" rel="nofollow">Screenshot</a></p>
  
  <p>Why?
  Suggestions?</p>
  
  <p>AndroidManifest.xml</p>
  
  <pre><code>    &lt;uses-sdk
         android:minSdkVersion="8"
         android:targetSdkVersion="17" /&gt;
  </code></pre>
  
  <p>XML in the activity for Spinner</p>
  
  <pre><code>    &lt;Spinner
              android:id="@+id/spnYear"
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:layout_alignBottom="@+id/btnScan"
              android:layout_marginBottom="92dp"
              android:layout_marginRight="22dp"
              android:layout_toLeftOf="@+id/btnScan"
              android:alpha="1"
              android:drawSelectorOnTop="true"/&gt;
  </code></pre>
  
  <p>Java activity code for Spinner initialization</p>
  
  <pre><code>ArrayAdapter&lt;String&gt; adapter = new ArrayAdapter&lt;String&gt;(this, android.R.layout.simple_spinner_item, Years);
  adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
  spnYear.setAdapter(adapter);
  spnYear.setSelection(spnYear.getCount() - 1);
  </code></pre>