Angularjs $http.get().then and binding to a list

Question

I have a list that looks like this:

<li ng-repeat="document in DisplayDocuments()" ng-class="IsFiltered(document.Filtered)">
    <span><input type="checkbox" name="docChecked" id="doc_{{document.Id}}" ng-model="document.Filtered" /></span>
    <span>{{document.Name}}</span>
</li>

I bind this list in my controller, to this:

$scope.Documents = $http.get('/Documents/DocumentsList/' + caseId).then(function(result) {
    return result.data;
});

When this runs, I dont get any results. when I remove the then method, I get three empty lines, making the count OK, but no information is displayed.

I know "everthing" else works, since I previously populated the list with jQuery, what am I doing wrong?

Here's the response from the server:

{Id:3f597acf-a026-45c5-8508-bc2383bc8c12, Name:ZZ_BL0164_Skisse BL0164_945111.pdf, Order:1,…}
{Id:46f51f1f-02eb-449a-9824-8633e8ae7f31, Name:ZB_BL0201_Firmaattest BL0201_945111.pdf, Order:1,…}
{Id:fddd1979-c917-4b32-9b83-b315f66984ed, Name:ZA_BL0228_Legitimasjonsskjema BL0228_945111.pdf,…}

Answer 1

$http methods return a promise, which can't be iterated, so you have to attach the results to the scope variable through the callbacks:

$scope.documents = [];
$http.get('/Documents/DocumentsList/' + caseId)
  .then(function(result) {
    $scope.documents = result.data;
});

Now, since this defines the documents variable only after the results are fetched, you need to initialise the documents variable on scope beforehand: $scope.documents = []. Otherwise, your ng-repeat will choke.

This way, ng-repeat will first return an empty list, because documents array is empty at first, but as soon as results are received, ng-repeat will run again because the `documents``have changed in the success callback.

Also, you might want to alter you ng-repeat expression to:

<li ng-repeat="document in documents" ng-class="IsFiltered(document.Filtered)">

because if your DisplayDocuments() function is making a call to the server, than this call will be executed many times over, due to the $digest cycles.

Answer 2

Promise returned from $http can not be binded directly (I dont exactly know why). I'm using wrapping service that works perfectly for me:

.factory('DocumentsList', function($http, $q){
    var d = $q.defer();
    $http.get('/DocumentsList').success(function(data){
        d.resolve(data);
    });
    return d.promise;
});

and bind to it in controller:

function Ctrl($scope, DocumentsList) {
    $scope.Documents = DocumentsList;
    ...
}

UPDATE!:

In Angular 1.2 auto-unwrap promises was removed. See http://docs.angularjs.org/guide/migration#templates-no-longer-automatically-unwrap-promises

Answer 3

Actually you get promise on $http.get.

Try to use followed flow:

<li ng-repeat="document in documents" ng-class="IsFiltered(document.Filtered)">
    <span><input type="checkbox" name="docChecked" id="doc_{{document.Id}}" ng-model="document.Filtered" /></span>
    <span>{{document.Name}}</span>
</li>

Where documents is your array.

$scope.documents = [];

$http.get('/Documents/DocumentsList/' + caseId).then(function(result) {
    result.data.forEach(function(val, i) { 
        $scope.documents.push(/* put data here*/);
    });
}, function(error) {
    alert(error.message);
});