angularJS：錯誤：未定義$ scope

Question

我想運行一個服務，當用戶訪問幾個特定頁面時，該服務會讀取總未讀消息。我爲此使用了resolve。我建立了一個通過http調用與後端進行通信的工廠，後端返回了總消息的數量，我想在html頁面中顯示，但是我得到的所有錯誤都是錯誤的。

(function() { 

    var countAllUnreads = function($location, $q, AuthService3) 
    { 
     var deferred = $q.defer(); 
     AuthService3.fetchUnreadNotifications().then(function (res) 
     { 
     console.log('this is me'); 
     $scope.numOfNotifications =res.data.totalUnread; 
     }); 
    } 
    angular.module('myApp', [ 
     'ngRoute', 
     'myApp.login', 
     'myApp.home', 
     'myApp.directory', 
     'myApp.forgotpassword', 
     'myApp.myProfile', 
    ]) 

    .factory('AuthService3', ["$http", "$location", function($http, $location){ 
     var baseUrl = 'api/'; 
     var fetchUnreadNotifications = function() 
     { 

     return $http.post(baseUrl + 'getAllUnreadNotifications');   
     }  

     return {fetchUnreadNotifications: fetchUnreadNotifications} ; 
    }]) 
    .config(['$routeProvider', function($routeProvider) { 
     $routeProvider 
     .when('/login', { 
      controller: 'LoginController', 
      templateUrl: 'app/components/login/loginView.html',  
      controllerAs: 'vm' 
     }) 
     .when('/forgotpassword', { 
      controller: 'ForgotpasswordController', 
      templateUrl: 'app/components/forgotpassword/forgotpasswordView.html', 
      controllerAs: 'vm' 
     }) 
     .when('/directory/:directoryType', { 
      controller: 'DirectoryController', 
      templateUrl: 'app/components/directory/directoryView.html', 
      resolve: {notifications:countAllUnreadsn,},  
      controllerAs: 'vm' 
     }) 
     .when('/home', { 
      controller: 'HomeController', 
      templateUrl: 'app/components/home/homeView.html', 
      resolve: {notifications:countAllUnreadsn,},   
      controllerAs: 'vm'   
     }) 
     .when('/myprofile', { 
      controller: 'MyProfileController', 
      templateUrl: 'app/components/profile/myProfileView.html', 
      resolve: {notifications:countAllUnreadsn,},  
      controllerAs: 'vm' 
     }) 
     .otherwise({ 
      redirectTo: '/login' 
     }); 
    }]); 

})(); 

Answer 1

問題是，您在加載通知的函數中使用$ scope。 $範圍將不可用，因爲它可能尚未創建。您需要返回一個承諾，並將解析的值作爲依賴項注入控制器。

var countAllUnreads = function($location, $q, AuthService3) 
    { 
     var deferred = $q.defer(); 
     AuthService3.fetchUnreadNotifications().then(function (res) 
     {  
     deferred.resolve(res.data.totalUnread); 
     }); 

     return deferred.promise; 
    }; 

而在您的控制器中，有'通知'的依賴關係。

Ex: function HomeController($scope, $http, notifications){ }