Working with select using AngularJS's ng-options
One thing to note is that ngModel is required for ngOptions to work... note the ng-model="blah"
which is saying "set $scope.blah to the selected value".
Try this:
<select ng-model="blah" ng-options="item.ID as item.Title for item in items"></select>
Here's more from AngularJS's documentation (if you haven't seen it):
for array data sources:
- label for value in array
- select as label for value in array
- label group by group for value in array = select as label group by group for value in array
for object data sources:
- label for (key , value) in object
- select as label for (key , value) in object
- label group by group for (key, value) in object
- select as label group by group for (key, value) in object
For some clarification on option tag values in AngularJS:
When you use ng-options
, the values of option tags written out by ng-options will always be the index of the array item the option tag relates to. This is because AngularJS actually allows you to select entire objects with select controls, and not just primitive types. For example:
app.controller('MainCtrl', function($scope) {
$scope.items = [
{ id: 1, name: 'foo' },
{ id: 2, name: 'bar' },
{ id: 3, name: 'blah' }
];
});
<div ng-controller="MainCtrl">
<select ng-model="selectedItem" ng-options="item as item.name for item in items"></select>
<pre>{{selectedItem | json}}</pre>
</div>
The above will allow you to select an entire object into $scope.selectedItem
directly. The point is, with AngularJS, you don't need to worry about what's in your option tag. Let AngularJS handle that; you should only care about what's in your model in your scope.
Here is a plunker demonstrating the behavior above, and showing the HTML written out
Dealing with the default option:
There are a few things I've failed to mention above relating to the default option.
Selecting the first option and removing the empty option:
You can do this by adding a simple ng-init
that sets the model (from ng-model
) to the first element in the items your repeating in ng-options
:
<select ng-init="foo = foo || items[0]" ng-model="foo" ng-options="item as item.name for item in items"></select>
Note: This could get a little crazy if foo
happens to be initialized properly to something "falsy". In that case, you'll want to handle the initialization of foo
in your controller, most likely.
Customizing the default option:
This is a little different; here all you need to do is add an option tag as a child of your select, with an empty value attribute, then customize its inner text:
<select ng-model="foo" ng-options="item as item.name for item in items">
<option value="">Nothing selected</option>
</select>
Note: In this case the "empty" option will stay there even after you select a different option. This isn't the case for the default behavior of selects under AngularJS.
A customized default option that hides after a selection is made:
If you wanted your customized default option to go away after you select a value, you can add an ng-hide attribute to your default option:
<select ng-model="foo" ng-options="item as item.name for item in items">
<option value="" ng-if="foo">Select something to remove me.</option>
</select>
I'm learning AngularJS and was struggling with selection as well. I know this question is already answered, but I wanted to share some more code nevertheless.
In my test I have two listboxes: car makes and car models. The models list is disabled until some make is selected. If selection in makes listbox is later reset (set to 'Select Make') then the models listbox becomes disabled again AND its selection is reset as well (to 'Select Model'). Makes are retrieved as a resource while models are just hard-coded.
Makes JSON:
[
{"code": "0", "name": "Select Make"},
{"code": "1", "name": "Acura"},
{"code": "2", "name": "Audi"}
]
services.js:
angular.module('makeServices', ['ngResource']).
factory('Make', function($resource){
return $resource('makes.json', {}, {
query: {method:'GET', isArray:true}
});
});
HTML file:
<div ng:controller="MakeModelCtrl">
<div>Make</div>
<select id="makeListBox"
ng-model="make.selected"
ng-options="make.code as make.name for make in makes"
ng-change="makeChanged(make.selected)">
</select>
<div>Model</div>
<select id="modelListBox"
ng-disabled="makeNotSelected"
ng-model="model.selected"
ng-options="model.code as model.name for model in models">
</select>
</div>
controllers.js:
function MakeModelCtrl($scope)
{
$scope.makeNotSelected = true;
$scope.make = {selected: "0"};
$scope.makes = Make.query({}, function (makes) {
$scope.make = {selected: makes[0].code};
});
$scope.makeChanged = function(selectedMakeCode) {
$scope.makeNotSelected = !selectedMakeCode;
if ($scope.makeNotSelected)
{
$scope.model = {selected: "0"};
}
};
$scope.models = [
{code:"0", name:"Select Model"},
{code:"1", name:"Model1"},
{code:"2", name:"Model2"}
];
$scope.model = {selected: "0"};
}
For some reason AngularJS allows to get me confused. Their documentation is pretty horrible on this. More good examples of variations would be welcome.
Anyway, I have a slight variation on Ben Lesh's answer.
My data collections looks like this:
items =
[
{ key:"AD",value:"Andorra" }
, { key:"AI",value:"Anguilla" }
, { key:"AO",value:"Angola" }
...etc..
]
Now
<select ng-model="countries" ng-options="item.key as item.value for item in items"></select>
still resulted in the options value to be the index (0, 1, 2, etc.).
Adding Track By fixed it for me:
<select ng-model="blah" ng-options="item.value for item in items track by item.key"></select>
I reckon it happens more often that you want to add an array of objects into an select list, so I am going to remember this one!
Be aware that from AngularJS 1.4 you can't use ng-options any more, but you need to use ng-repeat
on your option tag:
<select name="test">
<option ng-repeat="item in items" value="{{item.key}}">{{item.value}}</option>
</select>