Button to toggle on selecting a specific option from dropdown using AngularJs

Question

M stuck in Angular Js. I want to toggle the button between left and middle when I select a specific option from the dropdown.

By default the button is at middle. I want to toggle it to left only when I select "one" from the dropdown and remain at middle for the rest of the options.

This is the half baked code I have written (Index.html)

<div ng-controller="ButtonsCtrl">

<h4>Radio &amp; Uncheckable Radio</h4>
<select ng-model="selectedItem">
    <option ng-repeat="item in items" value="{{item}}">{{item}}</option>
  </select>
<div class="btn-group">
    <label class="btn btn-primary" ng-model="radioModel" btn-radio="'Left'">Left</label>
    <label class="btn btn-primary" ng-model="radioModel" btn-radio="'Middle'">Middle</label>

</div>

The Js file is as follows:

angular.module('ui.bootstrap.demo', ['ngAnimate', 'ui.bootstrap']);
angular.module('ui.bootstrap.demo').controller('ButtonsCtrl', function($scope){  $scope.radioModel = 'Middle';$scope.items = ['one','two','three','four'];});

Thanks in advance!!!

Answer 1

In order to achieve that, I would suggest adding an ng-change function to the <select> element, like so :

<select ng-model="selectedItem"  ng-change="changeFunction()">

What this function does, is to check if the current selected item is equal to "one" and if so, set the $scope.radioModdel to "Left". In all other cases, set it to "Middle". The code is below:

$scope.changeFunction = function(){
  if(this.selectedItem == 'one')
    $scope.radioModel = 'Left';
  else
    $scope.radioModel = 'Middle';
}

Here is a working plnkr .

You could read more about the way angular handles select elements on their documentation .

Thank you and have a nice day!