AngularJS错误：TypeError：v2.login不是一个函数

当我单击登录按钮但是在标题中继续收到错误消息时,我想调用登录​​功能.有人可以指出我脚本中的错误吗？

login.js代码如下：

/*global Firebase,angular,console*/

'use strict';
// Create a new app with the AngularFire module
var app = angular.module("runsheetApp");

app.controller("AuthCtrl",function ($scope,$firebaseAuth) {
    var ref = new Firebase("https://xxxxx.firebaseio.com");
    function login() {
        ref.authWithPassword({
            email    : "xxxxx",password : "xxxx"
        },function (error,authData) {
            if (error) {
                console.log("Login Failed!",error);
            } else {
                console.log("Authenticated successfully with payload:",authData);
            }
        });
    }
});

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.21/angular.min.js"></script>

而login.html的代码也在下面：

<div class="container" style="max-width: 300px">
    <form class="form-signin">       
      <h2 class="form-signin-heading" style="text-align: center">Please Sign In</h2>
      <input type="text" class="form-control" name="username" ng-model = "username" placeholder="Email Address" required="" autofocus="" />
        </br>
      <input type="password" class="form-control" name="password" ng-model = "password" placeholder="Password" required=""/>
        </br>
      <button class="btn btn-lg btn-primary btn-block" type="submit" ng-click="login()">Login</button>   
    </form>
  </div>

在AngularJS中调用该函数的视图必须在$范围内.

JS

// exposes login function in scope
$scope.login = login;

HTML

<div class="container" ng-controller="AuthCtrl" style="max-width: 300px"> <!-- I notice here for include ng-controller to your main div -->
<form class="form-signin">       
  <h2 class="form-signin-heading" style="text-align: center">Please Sign In</h2>
  <input type="text" class="form-control" name="username" ng-model = "username" placeholder="Email Address" required="" autofocus="" />
    </br>
  <input type="password" class="form-control" name="password" ng-model = "password" placeholder="Password" required=""/>
    </br>
  <button class="btn btn-lg btn-primary btn-block" type="submit" ng-click="login()">Login</button>   
</form>