title: Angularjs ui-select dropdown on-select function call issue
body: <p>In my AngularJS project I am using normal select dropdown and making a function call using ng-change which is perfectly working fine. Now I want to migrate the same dropdown to ui-select. But on-select function call is not working, I tried different ways but no luck. Please find my <a href="http://plnkr.co/edit/Ufhb0IfzrTlG3XLY2ahh?p=preview" rel="nofollow noreferrer">plnkr</a></p>
  
  <p>The following are the two ways I tried with ui-select:</p>
  
  <pre><code>&lt;ui-select ng-model="uiSelectedCustomer" theme="select2" on-select="getDataBasedonCustomer(uiSelectedCustomer)" style="min-width: 300px;"&gt;
      &lt;ui-select-match placeholder="Select a customer.."&gt;{{$select.selected.name}}&lt;/ui-select-match&gt;
      &lt;ui-select-choices repeat="cust in customers | filter: $select.search"&gt;
          &lt;div ng-bind-html="cust.name | highlight: $select.search"&gt;&lt;/div&gt;
      &lt;/ui-select-choices&gt;
  &lt;/ui-select&gt;
  
  
  &lt;ui-select ng-model="uiSelectedCustomer" theme="select2" on-select="getDataBasedonCustomer(uiSelectedCustomer)" style="min-width: 300px;"&gt;
      &lt;match placeholder="Select a customer in the list or search his name "&gt;{{$select.selected.name}}&lt;/match&gt;
      &lt;choices repeat="cust in customers | filter: $select.search"&gt;
          &lt;div ng-bind-html="cust.name | highlight: $select.search"&gt;&lt;/div&gt;
      &lt;/choices&gt;
  &lt;/ui-select&gt;
  </code></pre>