AngularJS解決承諾

Question

我正在學習如何使用示例中的 resolve，並將其應用於我的Todo腳本。

然后我意識到一個問題，該示例僅向我展示了當我第一次訪問此路線時如何解析GET調用以獲取Todo列表。

但是，在相同路徑的同一頁面中，我有一個添加按鈕來POST新的待辦事項項，還有一個清除按鈕來刪除已完成的項目。

查看我的$scope.addTodo = function() {和$scope.clearCompleted = function () {我希望在操作后再次解析我的TodoList。 我怎樣才能做到這一點？

這是我的代碼。 在我的代碼中，初始resolve: { todos: TodosListResl }正在工作，它命中TodosListResl函數並產生promise。 但是，當我想再次解析待辦事項列表時，我不知道如何處理addTodo和clearComplete 。

main.js

var todoApp = angular.module('TodoApp', ['ngResource', 'ui']);
todoApp.value('restTodo', 'api/1/todo/:id');

todoApp.config(function ($locationProvider, $routeProvider) {
    $routeProvider.when("/", { templateUrl: "Templates/_TodosList.html", 
        controller: TodosListCtrl, resolve: { todos: TodosListResl } });
    $routeProvider.otherwise({ redirectTo: '/' });
});

//copied from example, works great
function TodoCtrl($scope, $rootScope, $location) {
    $scope.alertMessage = "Welcome";
    $scope.alertClass = "alert-info hide";

    $rootScope.$on("$routeChangeStart", function (event, next, current) {
        $scope.alertMessage = "Loading...";
        $scope.alertClass = "progress-striped active progress-warning alert-info";
    });
    $rootScope.$on("$routeChangeSuccess", function (event, current, previous) {
        $scope.alertMessage = "OK";
        $scope.alertClass = "progress-success alert-success hide";

        $scope.newLocation = $location.path();
    });
    $rootScope.$on("$routeChangeError", 
        function (event, current, previous, rejection) {
        alert("ROUTE CHANGE ERROR: " + rejection);
        $scope.alertMessage = "Failed";
        $scope.alertClass = "progress-danger alert-error";
    });
}
//also copied from example, works great.
function TodosListResl($q, $route, $timeout, $resource, restTodo) {
    var deferred = $q.defer();
    var successCb = function(resp) {
        if(resp.responseStatus.errorCode) {
            deferred.reject(resp.responseStatus.message);
        } else {
            deferred.resolve(resp);
        }
    };
    $resource(restTodo).get({}, successCb);
    return deferred.promise;
}
//now, problem is here in addTodo and clearCompleted functions, 
//how do I call resolve to refresh my Todo List again? 
function TodosListCtrl($scope, $resource, restTodo, todos) {
    $scope.src = $resource(restTodo);
    $scope.todos = todos;
    $scope.totalTodos = ($scope.todos.result) ? $scope.todos.result.length : 0;

    $scope.addTodo = function() {
        $scope.src.save({ order: $scope.neworder, 
                          content: $scope.newcontent, 
                          done: false }); 
                        //successful callback, but how do I 'resolve' it?
    };
    $scope.clearCompleted = function () {
        var arr = [];
        _.each($scope.todos.result, function(todo) {
            if(todo.done) arr.push(todo.id);
        });
        if (arr.length > 0) $scope.src.delete({ ids: arr }); 
        //successful callback, but how do I 'resolve' it?
    };   
}

Answer 1

我想你錯過了resolve 。 resolve是“ 在數據加載之前延遲路由更改 。在您的情況下，您已經在路由中，並且您希望保持該路由。但是，您希望在成功回調時更新todos變量。”在這種情況下，您不想使用resolve 。而只需執行需要完成的操作。例如

$scope.addTodo = function() {
    $scope.src.save({ order: $scope.neworder, 
                      content: $scope.newcontent, 
                      done: false }, function () {
        todos.push({ order: $scope.neworder, 
                      content: $scope.newcontent, 
                      done: false });
    }); 
                    //successful callback, but how do I 'resolve' it?
};

作為一個側面點，我注意到你正在使用_最有可能來自Underscore庫。 你不需要使用另一個庫，因為Angular已經有了$angular.forEach() 。