title: Changing spinner arrow, Appcompat v21
body: <p>i have activities which i themed with my custom theme, but for spinner i choosed to style it with Appcompat v21 but i got this :
  <img src="https://i.stack.imgur.com/ZjcUk.png" alt="enter image description here"></p>
  
  <p><strong>So how to change the Spinner arrow to be black or blue if is there a way ?</strong></p>
  
  <p>i found this as similar question but doesn't have any answer : <a href="https://stackoverflow.com/questions/28561105/add-custom-spinner-arrow">https://stackoverflow.com/questions/28561105/add-custom-spinner-arrow</a>
  here is my spinner :</p>
  
  <pre><code>&lt;Spinner
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"
          android:id="@+id/spinner2"
          android:layout_marginTop="10dp"
          android:layout_centerInParent="true" /&gt;
  </code></pre>
  
  <p>i used this to style the spinner:</p>
  
  <pre><code> &lt;style name="MyTheme.SpinnerAppTheme" parent="Widget.AppCompat.Spinner"&gt;
      &lt;/style&gt;
  </code></pre>
  
  <p>this is how i use the adapter</p>
  
  <pre><code>   ArrayAdapter&lt;CharSequence&gt; adapter = ArrayAdapter.createFromResource(
                  getBaseContext(), R.array.listMedRes, android.R.layout.simple_spinner_item);
  </code></pre>
  
  <p>i just want to theme the spinner , thanks alot</p>