title: How to remove blank option from select when ng-model is empty?
body: <p>I have a scenario where I have a select dropdown with a refresh button and a plus button. When I click on the refresh button the model is set to null, but when I click on the plus button the dropdown is shown with empty option. So, I need to display the dropdown without empty option, where <code>ng-model</code> is null only.</p>
  
  <p>Here is my code:</p>
  
  <pre><code>&lt;div class="col-xs-6 npd"&gt;
      &lt;div ng-if="minAge==null"&gt;
          &lt;select ng-options="minAge.val as minAge.txt for minAge in ddloptions" ng-model="minAge" ng-change="ageCheck()"&gt;
           &lt;/select&gt;
          &lt;p&gt;Select &lt;br&gt;&lt;span&gt;Minimum age&lt;/span&gt;&lt;/p&gt;
      &lt;/div&gt;
      &lt;div ng-if="minAge!=null"&gt;
          &lt;a ng-click="minAgeRmv()"&gt;&lt;img src="images/prf-mprmv.png" /&gt;&lt;/a&gt;
          &lt;p&gt;Minimum age &lt;br&gt;&lt;span&gt;{{minAge}}&lt;/span&gt;&lt;/p&gt;
      &lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>Any help would be appreciated.</p>