Angularjs AngularFire routeProvider检查用户是否已登录

我试图通过检查用户对象是否存在来检查firebase用户是否已经登录。但是，当我刷新页面时，firebase函数会在firebase返回用户对象并重定向用户get之前异步运行页面加载，即使他们在技术上已登录

见下面的代码：

    app.config(['$routeProvider', '$locationProvider', '$waitForAuth','ngResource', function($routeProvider, $locationProvider, $waitForAuth, $ngResource) {

    $routeProvider
        .when('/', {
            templateUrl: 'views/home.html',
            controller: 'MainCtrl'
        })
        .when('/signup', {
            templateUrl: 'views/signup.html',
            controller: 'SignupCtrl'
        })
        .when('/classes', {
                templateUrl: 'views/class_lesson.html',
                controller: 'classLessonCtrl',
                resolve: {
                    "firebaseUser": function($waitForAuth) {

                        //user = firebase.auth().currentUser;
                        firebase.auth().onAuthStateChanged(function(user) {
                            user = firebase.auth().currentUser;
                            if (user){
                                console.log("user signed in");
                                return user;
                            }
                            else {
                                //window.location.replace('/signup');
                                console.log(user);
                                console.log("user not signed in");
                            }
                        });
                        *
                    }
                }

        });

    $locationProvider.html5Mode(true);

}]);

我四处搜索，发现一些人在使用Promise.all，以等待用户对象得到整理，但我不确定如何正确实现它。我能得到一些建议吗？还是有其他解决办法

var p = new Promise(function(resolve, reject) {

    // Do an async task async task and then...
    firebase.auth().onAuthStateChanged(function(user) {
        user = firebase.auth().currentUser;

    });

    if(/* good condition */user!=null (?) {
        resolve('Success!');
    }
    else {
        reject('Failure!');
    }
});

p.then(function() { 
    /* do something with the result */
}).catch(function() {
    /* error :( */
});

---

您需要解析程序返回某些内容。对于异步操作，这应该是$q服务在Angular中的承诺

resolve: {
  firebaseUser: function($waitForAuth) { // dunno what $waitForAuth is for
    return $q(function(resolve) {
      firebase.auth().onAuthStateChanged(resolve)
      // will resolve with null if not logegd in
    });
  }
}