I am building an Angular application that uses uib-typeahead and I am having trouble using the loading attribute. I would like to show a spinner while the typeahead is searching through a large dataset. Here is my code:

```
<input id="value"
   class="form-control input-sm" type="text"
   ng-model="filter"
   uib-typeahead="option.value for option in values | filter:$viewValue | limitTo:1500"
   placeholder="Select a value"
   typeahead-loading="is_Loading"
   typeahead-min-length="0"
   typeahead-editable="true">

   <span ng-if="is_Loading" id="myDiv"><img src="lib/images/ajax-spinner-large.gif" class="ajax-loader"/></span>

```

No image is showing when I am typing in the text box. Should I be assigning a $scope variable to is\_Loading?