Accessing the $index value from the selected option when using ng-change within a select element

Question

Accessing the $index value from the selected option when using ng-change within a select element

Although there are similar questions out there, I couldn't find one that addresses my specific need:

ngRepeat inside option-tag
ngChange inside select-tag

I am trying to retrieve the index of the selected option. Here is a snippet of my code:

<select data-placeholder="Choose" ng-model="pp.sif" name="myname" ng-change="onChangeSifra()">
    <option ng-repeat="item in sif.what track by $index" value="{{item.SIF}}">
        {{item.LABEL}}
    </option>
</select>

The use of ngClick inside the option-tag does not work on Chrome and IE, so that's not a viable solution. Additionally, using ngOption instead of ngRepeat is not an option due to the nature of the array of objects within sif.what.

Any suggestions?

EDIT: For those suggesting the switch to ngOption, here's why it won't work for me. I'm iterating through something like this:

$scope.sif.what = [
    {SIF: 1, LABEL: "label 1", SAVED: "save me 1"},
    {SIF: 2, LABEL: "label 2", SAVED: "save me 2"},
    {SIF: 3, LABEL: "label 3", SAVED: "save me 3"},
]

Basically, in a combobox, the label is displayed as the label, the "sif" is set as the value, and ngModel represents the value of "sif". However, during ngChange, I require access to the entire object, particularly sif.what(index) or $index.

Thank you.

javascript angularjs drop-down-menu

Answer 1

Answer №1

It may be tricky to return the index of the selected item without assigning it as the value of the option.

One possible solution is outlined below:

var app = angular.module('app', []);

app.controller('ctrl', function($scope, $filter) {
  $scope.sif = {'what': [{'SIF':'A'},{'SIF':'B'},{'SIF':'C'}]};
  $scope.onChangeSifra = function(item){
     $scope.selectedItem = $filter('filter')($scope.sif.what, {SIF : $scope.pp.sif}, true)[0];
     $scope.selectedItemIndex = $scope.sif.what.indexOf($scope.selectedItem);
  }
});

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/4.0.0-alpha.6/css/bootstrap.css" />

<body ng-app="app" ng-controller="ctrl">
  <div class="col-lg-12">
    <select data-placeholder="Choose" ng-model="pp.sif" name="sif" ng-change="onChangeSifra()">
      <option ng-repeat="item in sif.what track by $index" value="{{item.SIF}}">
          {{item.SIF}}
      </option>
    </select>
    
    <p>Selected : {{pp.sif}}</p>
    <p>Index : {{selectedItemIndex}}</p>    
  </div>
</body>

Answer 2

It may be tricky to return the index of the selected item without assigning it as the value of the option.

One possible solution is outlined below:

var app = angular.module('app', []);

app.controller('ctrl', function($scope, $filter) {
  $scope.sif = {'what': [{'SIF':'A'},{'SIF':'B'},{'SIF':'C'}]};
  $scope.onChangeSifra = function(item){
     $scope.selectedItem = $filter('filter')($scope.sif.what, {SIF : $scope.pp.sif}, true)[0];
     $scope.selectedItemIndex = $scope.sif.what.indexOf($scope.selectedItem);
  }
});

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/4.0.0-alpha.6/css/bootstrap.css" />

<body ng-app="app" ng-controller="ctrl">
  <div class="col-lg-12">
    <select data-placeholder="Choose" ng-model="pp.sif" name="sif" ng-change="onChangeSifra()">
      <option ng-repeat="item in sif.what track by $index" value="{{item.SIF}}">
          {{item.SIF}}
      </option>
    </select>
    
    <p>Selected : {{pp.sif}}</p>
    <p>Index : {{selectedItemIndex}}</p>    
  </div>
</body>

Answer 3

Answer №2

Consider utilizing ng-options instead of ng-repeat for a better approach:

<select data-placeholder="Choose" ng-model="pp.sif" name="sif" ng-change="onChangeSifra()" ng-options="{index: idx, item:item.SIF} as item.SIF for (idx, item) in sif.what">
</select>

Answer 4

Consider utilizing ng-options instead of ng-repeat for a better approach:

<select data-placeholder="Choose" ng-model="pp.sif" name="sif" ng-change="onChangeSifra()" ng-options="{index: idx, item:item.SIF} as item.SIF for (idx, item) in sif.what">
</select>

Answer 5

Answer №3

Insight : consider using the ngOptions attribute in place of ng-repeat.

Utilize the array.indexOf() method to determine the index of the selected item.

EXAMPLE

var myApp = angular.module('myApp',[]);

myApp.controller('MyCtrl',function($scope) {
    $scope.sif = {
      "what": [
        {
          "SIF":1
        },
        {
          "SIF":2
        },
        {
          "SIF":3
        }
      ]
    };
  $scope.onChangeSifra = function(selectedItem) {
    console.log($scope.sif.what.indexOf(selectedItem));
  }
});

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app="myApp" ng-controller="MyCtrl">
  <select data-placeholder="Choose" ng-model="pplsif" name="sif" ng-change="onChangeSifra(pplsif)" ng-options="item.SIF for item in sif.what">
</select>
</div>

Answer 6

Insight : consider using the ngOptions attribute in place of ng-repeat.

Utilize the array.indexOf() method to determine the index of the selected item.

EXAMPLE

var myApp = angular.module('myApp',[]);

myApp.controller('MyCtrl',function($scope) {
    $scope.sif = {
      "what": [
        {
          "SIF":1
        },
        {
          "SIF":2
        },
        {
          "SIF":3
        }
      ]
    };
  $scope.onChangeSifra = function(selectedItem) {
    console.log($scope.sif.what.indexOf(selectedItem));
  }
});

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app="myApp" ng-controller="MyCtrl">
  <select data-placeholder="Choose" ng-model="pplsif" name="sif" ng-change="onChangeSifra(pplsif)" ng-options="item.SIF for item in sif.what">
</select>
</div>

Answer 7

Answer №4

Feel free to give this login a shot

<select ng-model="optIndex" ng-change="getIndex()">
<option ng-repeat="opt in opts" value={{$index}}></option>
<select>

$scope.getIndex = function(){console.log($scope.optIndex);}

You are now able to retrieve your index using this code snippet :)

Answer 8

Feel free to give this login a shot

<select ng-model="optIndex" ng-change="getIndex()">
<option ng-repeat="opt in opts" value={{$index}}></option>
<select>

$scope.getIndex = function(){console.log($scope.optIndex);}

You are now able to retrieve your index using this code snippet :)

Accessing the $index value from the selected option when using ng-change within a select element

Answer №1

Answer №2

Answer №3

Answer №4

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