I have created a Widget Modal in ServicePortal. I want to control its visibility and mandatory

[Misbah Sayyed]

I have created a Widget Modal in Service Portal. I want to make this 'Comments' field visible and mandatory only if we select Other in 'Rejection Reason' Select field..

below is my html code:

<div>
<label ><b>Rejection Reason:</b></label>
<select ng-model="data.value" style="height:80%; width:15%; margin-left: 2%; padding-top: 3px; padding-bottom: 3px;">
<option value="Incorrect Approver">Incorrect Approver</option>
<option value="Other">Other</option>

</select><br><br>
<label ><b>Comments:</b></label>
<textarea class="form-control" ng-model="data.comments"></textarea>
<br><br>
<button class="btn btn-primary btn-sm m-l-xs" ng-click="c.reject(data.value,data.comments)">
Reject
</button>
<!-- your widget template -->
</div>

CLIENT SCRIPT

function($window) {

  /* widget controller */

  var c = this;

c.reject=function(value,comments)

{

c.data.check='yes';

c.data.rejection_reason = value;

c.data.comments= comments;

c.server.update();

$window.location.reload();

}

}

PLEASE SEE THE BELOW IMAGE FOR REFERENCE AND HELP ME WITH THE SOLUTION

@Dr Atul G- LNG  

@Maik Skoddow @Mark Roethof @Gaurav Shirsat  @tltoulson @Ankur Bawiskar @Chuck Tomasi @Saurav11