AngularJS 1.6 application bug: turning items pagin

问题:

I am making a small Contacts application with Bootstrap 4 and AngularJS v1.6.6.

The application simply displays an Users JSON. Since the JSON returns a large number of users, the application also has a pagination feature.

The pagination worked fine as part of the app's controller, but since I tried to turn it into a service, it does not work anymore.

See a functional version of the application, with the pagination inside the controller HERE.

The application controller:

// Create an Angular module named "contactsApp"
var app = angular.module("contactsApp", []);

// Create controller for the "contactsApp" module
app.controller("contactsCtrl", ["$scope", "$http", "$filter", "paginationService", function($scope, $http, $filter) {
  var url = "https://randomuser.me/api/?&results=100&inc=name,location,email,cell,picture";
  $scope.contactList = [];
  $scope.search = "";
  $scope.filterList = function() {
    var oldList = $scope.contactList || [];
    $scope.contactList = $filter('filter')($scope.contacts, $scope.search);
    if (oldList.length != $scope.contactList.length) {
      $scope.pageNum = 1;
      $scope.startAt = 0;
    };
    $scope.itemsCount = $scope.contactList.length;
    $scope.pageMax = Math.ceil($scope.itemsCount / $scope.perPage);
  };

  $http.get(url)
    .then(function(data) {
      // contacts arary
      $scope.contacts = data.data.results;
      $scope.filterList();

      // Pagination Service
      $scope.paginateContacts = function(){
        $scope.pagination = paginationService.paginateContacts();
      }

    });
}]);

The service:

app.factory('paginationService', function(){
     return {
        paginateContacts:  function(){
            // Paginate
            $scope.pageNum = 1;
            $scope.perPage = 24;
            $scope.startAt = 0;
            $scope.filterList();

            $scope.currentPage = function(index) {
                $scope.pageNum = index + 1;
                $scope.startAt = index * $scope.perPage;
            };

            $scope.prevPage = function() {
                if ($scope.pageNum > 1) {
                    $scope.pageNum = $scope.pageNum - 1;
                    $scope.startAt = ($scope.pageNum - 1) * $scope.perPage;
                }
            };

            $scope.nextPage = function() {
                if ($scope.pageNum < $scope.pageMax) {
                    $scope.pageNum = $scope.pageNum + 1;
                    $scope.startAt = ($scope.pageNum - 1) * $scope.perPage;
                }
            };
        }
    }
});

In the view:

<div ng-if="pageMax > 1">
        <ul class="pagination pagination-sm justify-content-center">
            <li class="page-item"><a href="#" ng-click="prevPage()"><i class="fa fa-chevron-left"></i></a></li>
            <li ng-repeat="n in [].constructor(pageMax) track by $index" ng-class="{true: 'active'}[$index == pageNum - 1]">
                <a href="#" ng-click="currentPage($index)">{{$index+1}}</a>
            </li>
            <li><a href="#" ng-click="nextPage()"><i class="fa fa-chevron-right"></i></a></li>
        </ul>
</div>

The service file is included in the project (correctly, in my opinion) after the app.js file:

<script src="js/app.js"></script>
<script src="js/paginationService.js"></script>

I am not an advanced AngularJS user so I don't know: what is missing?

回答1:

It appears that the service needs to be defined before the controller, otherwise it cannot be injected properly.

So you could either move the paginationService into app.js:

var app = angular.module("contactsApp", []);
app.factory('paginationService', function(){
    //...
});
app.controller("contactsCtrl", ["$scope", "$http", "$filter", "paginationService", function($scope, $http, $filter) {
    //...
});

Or else move the controller out to a separate file that is included after the paginationServices.js file.

Take a look at this plunker. Try modifying line 6 - remove character 5, i.e. the space that separates the star and slash that would close the multi-line comment.