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

使用Angular Version 6和Bootstrap 4.1

我能够做到如下所示。

在下面的例子中,当URL看到'/contact'时,引导活动就会被添加到html标记中。当URL改变时,它就会被删除。

<ul>
<li class="nav-item" routerLink="/contact" routerLinkActive="active">
    <a class="nav-link" href="/contact">Contact</a>
</li>
</ul>

这个指令允许你在链接的时候给元素添加一个CSS类 路由激活。

在Angular网站上阅读更多信息

其他回答

根据@kfis的回答,这是评论,我的建议,最终指令如下:

.directive('activeLink', ['$location', function (location) {
    return {
      restrict: 'A',
      link: function(scope, element, attrs, controller) {
        var clazz = attrs.activeLink;        
        var path = attrs.href||attrs.ngHref;
        path = path.substring(1); //hack because path does not return including hashbang
        scope.location = location;
        scope.$watch('window.location.href', function () {
          var newPath = (window.location.pathname + window.location.search).substr(1);
          if (path === newPath) {
            element.addClass(clazz);
          } else {
            element.removeClass(clazz);
          }
        });
      }
    };
  }]);

下面是它在html中的用法: < div ng-app = "链接" > <a href="#/one" active-link="active"> one </a> <a href="#/two" active-link="active">One</a> <a href="#" active-link="active">home</a> < / div > 之后用css样式: .活跃{颜色:红色;}

我建议在链接上使用指令。

但它还不完美。小心哈希邦;)

下面是指令的javascript代码:

angular.module('link', []).
  directive('activeLink', ['$location', function (location) {
    return {
      restrict: 'A',
      link: function(scope, element, attrs, controller) {
        var clazz = attrs.activeLink;
        var path = attrs.href;
        path = path.substring(1); //hack because path does not return including hashbang
        scope.location = location;
        scope.$watch('location.path()', function (newPath) {
          if (path === newPath) {
            element.addClass(clazz);
          } else {
            element.removeClass(clazz);
          }
        });
      }
    };
  }]);

下面是它在html中的用法:

<div ng-app="link">
  <a href="#/one" active-link="active">One</a>
  <a href="#/two" active-link="active">One</a>
  <a href="#" active-link="active">home</a>
</div>

之后用css样式:

.active { color: red; }

这里是另一个突出显示活动链接的指令。

主要特点:

适用于包含动态角度表达式的href 兼容散列导航 与Bootstrap兼容,其中活动类应该应用到父li而不是链接本身 允许使链接活动,如果任何嵌套的路径是活动的 允许禁用make链接,如果它不是活动的

代码:

.directive('activeLink', ['$location', 
function($location) {
    return {
        restrict: 'A',
        link: function(scope, elem, attrs) {
            var path = attrs.activeLink ? 'activeLink' : 'href';
            var target = angular.isDefined(attrs.activeLinkParent) ? elem.parent() : elem;
            var disabled = angular.isDefined(attrs.activeLinkDisabled) ? true : false;
            var nested = angular.isDefined(attrs.activeLinkNested) ? true : false;

            function inPath(needle, haystack) {
                var current = (haystack == needle);
                if (nested) {
                    current |= (haystack.indexOf(needle + '/') == 0);
                }

                return current;
            }

            function toggleClass(linkPath, locationPath) {
                // remove hash prefix and trailing slashes
                linkPath = linkPath ? linkPath.replace(/^#!/, '').replace(/\/+$/, '') : '';
                locationPath = locationPath.replace(/\/+$/, '');

                if (linkPath && inPath(linkPath, locationPath)) {
                    target.addClass('active');
                    if (disabled) {
                        target.removeClass('disabled');
                    }
                } else {
                    target.removeClass('active');
                    if (disabled) {
                        target.addClass('disabled');
                    }
                }
            }

            // watch if attribute value changes / evaluated
            attrs.$observe(path, function(linkPath) {
                toggleClass(linkPath, $location.path());
            });

            // watch if location changes
            scope.$watch(
                function() {
                    return $location.path(); 
                }, 
                function(newPath) {
                    toggleClass(attrs[path], newPath);
                }
            );
        }
    };
}
]);

用法:

angular表达式的简单例子,让我们输入$scope。Var = 2,那么链接将是活跃的,如果位置是/url/2:

<a href="#!/url/{{var}}" active-link>

Bootstrap示例,parent li将获得活动类:

<li>
    <a href="#!/url" active-link active-link-parent>
</li>

以嵌套url为例,如果任何嵌套url是活动的,链接将是活动的(即/url/1, /url/2, url/1/2/…)

<a href="#!/url" active-link active-link-nested>

复杂的例子,链接指向一个url (/url1),但如果选择另一个url (/url2)将是活动的:

<a href="#!/url1" active-link="#!/url2" active-link-nested>

以禁用链接为例,如果它不是活动的,它将有'disabled'类:

<a href="#!/url" active-link active-link-disabled>

所有active-link-*属性都可以在任何组合中使用,因此可以实现非常复杂的条件。

我做了一个纯angular模块(没有jQuery),它也可以处理包含数据的散列url。(例如:# /这个/ /路径?这=一些=数据)

您只需将模块作为依赖项添加并自动激活到菜单的一个祖先。是这样的:

<ul auto-active>
    <li><a href="#/">main</a></li>
    <li><a href="#/first">first</a></li>
    <li><a href="#/second">second</a></li>
    <li><a href="#/third">third</a></li>
</ul>

这个模块是这样的:

(function () {
    angular.module('autoActive', [])
        .directive('autoActive', ['$location', function ($location) {
        return {
            restrict: 'A',
            scope: false,
            link: function (scope, element) {
                function setActive() {
                    var path = $location.path();
                    if (path) {
                        angular.forEach(element.find('li'), function (li) {
                            var anchor = li.querySelector('a');
                            if (anchor.href.match('#' + path + '(?=\\?|$)')) {
                                angular.element(li).addClass('active');
                            } else {
                                angular.element(li).removeClass('active');
                            }
                        });
                    }
                }

                setActive();

                scope.$on('$locationChangeSuccess', setActive);
            }
        }
    }]);
}());

(当然,你可以只使用指令部分)

值得注意的是,这并不适用于空哈希值(例如example.com/#或仅example.com),它至少需要example.com/#/或仅example.com#/。但这是自动发生的ngResource之类的。

这是小提琴:http://jsfiddle.net/gy2an/8/

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();
    });
  });
});