Angularjs Dropdown OnChange Selected Text and Value

Question

I am new to AngularJS and trying to get Selected Text and Value from Dropdown. I followed a lot of tutorials with still unable to get there. SelectedValue and SelectedText are always undefined. Below is my code:

Html:

<div ng-app="SelectApp">
<div ng-controller="selectController">
    <select name="category-group" id="categoryGroup" class="form-control" ng-model="itemSelected" ng-change="onCategoryChange(itemSelected)">
        <option value="0">Select a category...</option>
        <option ng-repeat="category in categories" value="{{category.id}}"
             ng-disabled="category.disabled" ng-class="{'mainCategory' : category.disabled}">
             {{category.name}}
        </option>
     </select>
</div>

Js:

'use strict';
var app = angular.module('SelectApp', [ ]);
app.controller('selectController', ['$scope', '$window', function ($scope, $window) {

$scope.categories = [       
   { id: 1, name: "- Vehicles -", disabled: true },
   { id: 2, name: "Cars" },
   { id: 3, name: "Commercial vehicles", disabled: false },
   { id: 4, name: "Motorcycles", disabled: false },
   { id: 5, name: "Car & Motorcycle Equipment", disabled: false },
   { id: 6, name: "Boats", disabled: false },
   { id: 7, name: "Other Vehicles", disabled: false },
   { id: 8, name: "- House and Children -", disabled: true },
   { id: 9, name: "Appliances", disabled: false },
   { id: 10, name: "Inside", disabled: false },
   { id: 11, name: "Games and Clothing", disabled: false },
   { id: 12, name: "Garden", disabled: false }
];

$scope.onCategoryChange = function () {

    $window.alert("Selected Value: " + $scope.itemSelected.id + "\nSelected Text: " + $scope.itemSelected.name);

};
}]);

And one more thing, I have defined my first item as Select a category... then Why first item in Dropdown is always empty.

Below is my fiddle sample. http://jsfiddle.net/Qgmz7/136/

Solution 1

That's because, your model itemSelected captures the current value of your select drop down which is nothing but the value attribute of your option element. You have

<option ng-repeat="category in categories" value="{{category.id}}">

in your code, so in the rendered version, you'll get

<option ng-repeat="category in categories" value="0">

but you're expecting itemSelected to be your category object and any attempt to query id or other property will return undefined.

You can use ng-options with group by with little bit of change to your data or you can use normal ng-repeat, get the selectedIndex and lookup the category object from your categories list using that index. Showcasing the first approach here.

HTML

<select name="category-group" id="categoryGroup" 
        ng-model="itemSelected" ng-change="onCategoryChange(itemSelected)" 
        ng-options="category.name group by category.group for category in categories">
</select>

Updated Data

$scope.categories = [
       { id: 0, name: "Select a category..."},
       { id: 1, name: "Cars", group : "- Vehicles -" },
       { id: 2, name: "Commercial vehicles", group : "- Vehicles -" },
       { id: 3, name: "Motorcycles", group : "- Vehicles -" }
 ];

 $scope.itemSelected = $scope.categories[0];

Instead of disabled property, you can add a group property which can be used in group by.

Here' an updated Fiddle to illustrate the idea.

Solution 2

You should use ng-options to set object to your ng-model value on change of you select options.

Markup

<select name="category-group" id="categoryGroup" class="form-control" 
  ng-model="itemSelected" ng-change="onCategoryChange(itemSelected)" 
  ng-options="category.name for category in categories">
    <option value="0">Select a category...</option>
</select>

Fiddle Here

Update

For persisting style you have to use ng-repeat there, in that case you will only have id binded to your ng-model and while retrieving whole object you need to filter your data.

$scope.onCategoryChange = function () {
    var currentSelected = $filter('filter')($scope.categories, {id: $scope.itemSelected})[0]
    $window.alert("Selected Value: " + currentSelected.id + "\nSelected Text: " + currentSelected.name);
};

Updated Fiddle

Solution 3

<div ng-app="SelectApp">
    <div ng-controller="selectController">
    <select ng-change='onCategoryChange()' ng-model="itemSelected" ng-options="category.name for category in categories">
        <option value="">-- category --</option>
    </select>
</div>

//http://jsbin.com/zajipe/edit?html,js,output

Solution 4

A little change in your onCategoryChange() should work:

$scope.onCategoryChange = function () {
        $window.alert("Selected Value: " + $scope.categories[$scope.itemSelected - 1].id + "\nSelected Text: " + $scope.categories[$scope.itemSelected -1].name);

    };

JSFiddle: http://jsfiddle.net/Qgmz7/144/

Solution 5

ngChange only returns the value of your selected option and that's why you don't get the whole data.

Here's a working solution without changing your markup logic.

Markup:

<select
    name="category-group"
    id="categoryGroup"
    class="form-control"
    ng-model="id"     
    ng-change="onCategoryChange(id)">

ngChange handler:

 $scope.onCategoryChange = function (id) {
        //get selected item data from categories
        var selectedIndex = $scope.categories.map(function(obj) { return obj.id; }).indexOf( parseInt(id) );
        var itemSelected = $scope.categories[selectedIndex];

        $window.alert("Selected Value: " + itemSelected.id + "\nSelected Text: " + itemSelected.name);

    };

---

Another solution (little bit dirty) would be to change only the value of your options into something like this:

<option .... value="{{category.id}}|{{category.name}}">

...and inside your actual ngChange handler, just split the value to get all the values as an array:

$scope.onCategoryChange = function (itemSelected) {
    $scope.itemSelected = itemSelected.split('|'); //string value to array
    $window.alert("Selected Value: " + $scope.itemSelected[0] + "\nSelected Text: " + $scope.itemSelected[1]);

};

View more solutions

Comments

[Usman Khalid]

It works but my css logic is gone. If you see my sample. - Vehicles - and - House and Children - are disabled and using different css.

[Pankaj Parkar]

@UsmanKhalid take a look at updated fiddle..which will work as you want

[Arkantos]

This example will keep the group headers using optgroup in select element rendered by group by clause in ng-options. Hope this helps :)

[Usman Khalid]

Thanks a lot. It is working fine but why dropdown is empty for the first time?

[Pankaj Parkar]

are you crazy to that..how come $scope.categories[$scope.itemSelected] will select a value from categories?

[Usman Khalid]

that's good solution but why dropdown is empty for the first time.

[Arkantos]

That's because we've not set any default value for itemSelected in our controller. Add your default value to your categories list and set that value as shown here

[Usman Khalid]

Thanks a lot Ankantos. Very good solution and something new to learn. :)

[Arkantos]

Glad to be of help :)

[ArBro]

$scope.itemSelected Will return the value (as a Number) of the selected item in the option list. By passing it to the object You are able to select the n-property of the object and you will have access to the data.

[Pankaj Parkar]

could you please look at your fiddle it is showing wrong value as its considering index of an array

[ArBro]

Updated the code. It should output the right values now.

[Pankaj Parkar]

No dude that could harm..if suppose you have skipped one/two element id and then took third one..then $scope.itemSelected - 1 will won't work..