angular ui 路由错误,因为抽象 =true 时无法从状态解析 'Employee.root'

angular ui route Error as Could not resolve 'Employee.root' from state when abstract =true

为什么我收到此错误无法从状态中解析 'Employee.root' 当我使用 abstract true 时。

<body ng-app="SuperApp">
                <li><a ui-sref="Employee.root()">Employees</a></li>

.js代码

app.config(function ($stateProvider, $urlRouterProvider, $locationProvider) {
    $urlRouterProvider.otherwise('/')
    $stateProvider
        .state('root', {
            abstract:true,
            views:{
                '@':{
                    templateUrl: '/Kpmg/Dummy/_LayoutPage.html'
                }
            }

        })
    $stateProvider.state('root.Employee', {
        url: 'contact',
        templateUrl: '/Kpmg/Dummy/someOther/Contact1.html',
        controller: 'abc'
    })

Contact1.html

  <div ng-controller="abc">
        <h3>This is Contact</h3>
    </div>
  <div ui-view></div>

应该是

  <li><a ui-sref="root.Employee">Employees</a></li>