AngularJS在为当前页面的链接设置一个活动类方面有任何帮助吗?

我想一定有什么神奇的方法可以做到,但我似乎找不到。

我的菜单是这样的:

 <ul>
   <li><a class="active" href="/tasks">Tasks</a>
   <li><a href="/actions">Tasks</a>
 </ul>

我在我的路由中为它们每个都有控制器:TasksController和ActionsController。

但是我想不出一种方法将a链接上的“活动”类绑定到控制器。

有提示吗?


当前回答

我找到了最简单的解决办法。只是比较HTML中的indexOf

var myApp = angular.module('myApp', []);

myApp.run(function($rootScope) {
    $rootScope.$on("$locationChangeStart", function(event, next, current) { 
         $rootScope.isCurrentPath = $location.path();  
    });
});



<li class="{{isCurrentPath.indexOf('help')>-1 ? 'active' : '' }}">
<a href="/#/help/">
          Help
        </a>
</li>

其他回答

对于AngularUI路由器用户:

<a ui-sref-active="active" ui-sref="app">

这将在选中的对象上放置一个活动类。

来自@Renan-tomal-fernandes的回答很好,但需要进行一些改进才能正确工作。 事实上,它总是在触发时检测到到主页(/)的链接,即使你在另一个部分。

我稍微改进了一下,这是代码。 我使用Bootstrap,所以活动部分是在<li>元素,而不是<a>。

控制器

$scope.getClass = function(path) {
    var cur_path = $location.path().substr(0, path.length);
    if (cur_path == path) {
        if($location.path().substr(0).length > 1 && path.length == 1 )
            return "";
        else
            return "active";
    } else {
        return "";
    }
}

模板

<div class="nav-collapse collapse">
  <ul class="nav">
    <li ng-class="getClass('/')"><a href="#/">Home</a></li>
    <li ng-class="getClass('/contents/')"><a href="#/contests/">Contents</a></li>
    <li ng-class="getClass('/data/')"><a href="#/data/">Your data</a></li>
  </ul>
</div>

我刚刚写了一个指令。

用法:

<ul class="nav navbar-nav">
  <li active><a href="#/link1">Link 1</a></li>
  <li active><a href="#/link2">Link 2</a></li>
</ul>

实现:

angular.module('appName')
  .directive('active', function ($location, $timeout) {
    return {
      restrict: 'A',
      link: function (scope, element, attrs) {
        // Whenever the user navigates to a different page...
        scope.$on('$routeChangeSuccess', function () {
          // Defer for other directives to load first; this is important
          // so that in case other directives are used that this directive
          // depends on, such as ng-href, the href is evaluated before
          // it's checked here.
          $timeout(function () {
            // Find link inside li element
            var $link = element.children('a').first();

            // Get current location
            var currentPath = $location.path();

            // Get location the link is pointing to
            var linkPath = $link.attr('href').split('#').pop();

            // If they are the same, it means the user is currently
            // on the same page the link would point to, so it should
            // be marked as such
            if (currentPath === linkPath) {
              $(element).addClass('active');
            } else {
              // If they're not the same, a li element that is currently
              // marked as active needs to be "un-marked"
              element.removeClass('active');
            }
          });
        });
      }
    };
  });

测试:

'use strict';

describe('Directive: active', function () {

  // load the directive's module
  beforeEach(module('appName'));

  var element,
      scope,
      location,
      compile,
      rootScope,
      timeout;

  beforeEach(inject(function ($rootScope, $location, $compile, $timeout) {
    scope = $rootScope.$new();
    location = $location;
    compile = $compile;
    rootScope = $rootScope;
    timeout = $timeout;
  }));

  describe('with an active link', function () {
    beforeEach(function () {
      // Trigger location change
      location.path('/foo');
    });

    describe('href', function () {
      beforeEach(function () {
        // Create and compile element with directive; note that the link
        // is the same as the current location after the location change.
        element = angular.element('<li active><a href="#/foo">Foo</a></li>');
        element = compile(element)(scope);

        // Broadcast location change; the directive waits for this signal
        rootScope.$broadcast('$routeChangeSuccess');

        // Flush timeout so we don't have to write asynchronous tests.
        // The directive defers any action using a timeout so that other
        // directives it might depend on, such as ng-href, are evaluated
        // beforehand.
        timeout.flush();
      });

      it('adds the class "active" to the li', function () {
        expect(element.hasClass('active')).toBeTruthy();
      });
    });

    describe('ng-href', function () {
      beforeEach(function () {
        // Create and compile element with directive; note that the link
        // is the same as the current location after the location change;
        // however this time with an ng-href instead of an href.
        element = angular.element('<li active><a ng-href="#/foo">Foo</a></li>');
        element = compile(element)(scope);

        // Broadcast location change; the directive waits for this signal
        rootScope.$broadcast('$routeChangeSuccess');

        // Flush timeout so we don't have to write asynchronous tests.
        // The directive defers any action using a timeout so that other
        // directives it might depend on, such as ng-href, are evaluated
        // beforehand.
        timeout.flush();
      });

      it('also works with ng-href', function () {
        expect(element.hasClass('active')).toBeTruthy();
      });
    });
  });

  describe('with an inactive link', function () {
    beforeEach(function () {
      // Trigger location change
      location.path('/bar');

      // Create and compile element with directive; note that the link
      // is the NOT same as the current location after the location change.
      element = angular.element('<li active><a href="#/foo">Foo</a></li>');
      element = compile(element)(scope);

      // Broadcast location change; the directive waits for this signal
      rootScope.$broadcast('$routeChangeSuccess');

      // Flush timeout so we don't have to write asynchronous tests.
      // The directive defers any action using a timeout so that other
      // directives it might depend on, such as ng-href, are evaluated
      // beforehand.
      timeout.flush();
    });

    it('does not add the class "active" to the li', function () {
      expect(element.hasClass('active')).not.toBeTruthy();
    });
  });

  describe('with a formerly active link', function () {
    beforeEach(function () {
      // Trigger location change
      location.path('/bar');

      // Create and compile element with directive; note that the link
      // is the same as the current location after the location change.
      // Also not that the li element already has the class "active".
      // This is to make sure that a link that is active right now will
      // not be active anymore when the user navigates somewhere else.
      element = angular.element('<li class="active" active><a href="#/foo">Foo</a></li>');
      element = compile(element)(scope);

      // Broadcast location change; the directive waits for this signal
      rootScope.$broadcast('$routeChangeSuccess');

      // Flush timeout so we don't have to write asynchronous tests.
      // The directive defers any action using a timeout so that other
      // directives it might depend on, such as ng-href, are evaluated
      // beforehand.
      timeout.flush();
    });

    it('removes the "active" class from the li', function () {
      expect(element.hasClass('active')).not.toBeTruthy();
    });
  });
});

使用指令(因为我们在这里做的是DOM操作),下面可能是最接近“angular方式”的方法:

$scope.timeFilters = [
  {'value':3600,'label':'1 hour'},
  {'value':10800,'label':'3 hours'},
  {'value':21600,'label':'6 hours'},
  {'value':43200,'label':'12 hours'},
  {'value':86400,'label':'24 hours'},
  {'value':604800,'label':'1 week'}
]

angular.module('whatever', []).directive('filter',function(){
return{
    restrict: 'A',
    template: '<li ng-repeat="time in timeFilters" class="filterItem"><a ng-click="changeTimeFilter(time)">{{time.label}}</a></li>',
    link: function linkFn(scope, lElement, attrs){

        var menuContext = attrs.filter;

        scope.changeTimeFilter = function(newTime){
          scope.selectedtimefilter = newTime;

        }

        lElement.bind('click', function(cevent){
            var currentSelection = angular.element(cevent.srcElement).parent();
            var previousSelection = scope[menuContext];

            if(previousSelection !== currentSelection){
                if(previousSelection){
                    angular.element(previousSelection).removeClass('active')
                }
                scope[menuContext] = currentSelection;

                scope.$apply(function(){
                    currentSelection.addClass('active');
                })
            }
        })
    }
}
})

然后你的HTML看起来像这样:

<ul class="dropdown-menu" filter="times"></ul>

在我的例子中,我通过创建一个负责导航的简单控制器来解决这个问题

angular.module('DemoApp')
  .controller('NavigationCtrl', ['$scope', '$location', function ($scope, $location) {
    $scope.isCurrentPath = function (path) {
      return $location.path() == path;
    };
  }]);

只需像这样在元素中添加ng-class:

<ul class="nav" ng-controller="NavigationCtrl">
  <li ng-class="{ active: isCurrentPath('/') }"><a href="#/">Home</a></li>
  <li ng-class="{ active: isCurrentPath('/about') }"><a href="#/about">About</a></li>
  <li ng-class="{ active: isCurrentPath('/contact') }"><a href="#/contact">Contact</a></li>
</ul>