如何在AngularJS中使用自己的作用域*从自定义指令*中访问父作用域?

内容来源于 Stack Overflow,并遵循CC BY-SA 3.0许可协议进行翻译与使用

  • 回答 (6)
  • 关注 (0)
  • 查看 (253)

我正在寻找在指令中访问“parent”范围的任何方式。任何范围的组合,转换,要求,从上面传入变量(或范围本身)等等。我完全愿意向后弯曲,但我想避免一些完全不牢靠或无法维护的东西。例如,我知道我现在可以通过$scope从预链接参数中迭代它的$sibling用于查找概念“parent”的范围。

我真正想要的是$watch父作用域中的表达式。如果我能做到的话,我就能完成我在这里想要做的事情:AngularJS--如何用变量呈现一个部分?

代码示例值:

app.directive('watchingMyParentScope', function() {
    return {
        require: /* ? */,
        scope: /* ? */,
        transclude: /* ? */,
        controller: /* ? */,
        compile: function(el,attr,trans) {
            // Can I get the $parent from the transclusion function somehow?
            return {
                pre: function($s, $e, $a, parentControl) {
                    // Can I get the $parent from the parent controller?
                    // By setting this.$scope = $scope from within that controller?

                    // Can I get the $parent from the current $scope?

                    // Can I pass the $parent scope in as an attribute and define
                    // it as part of this directive's scope definition?

                    // What don't I understand about how directives work and
                    // how their scope is related to their parent?
                },
                post: function($s, $e, $a, parentControl) {
                    // Has my situation improved by the time the postLink is called?
                }
            }
        }
    };
});
提问于
用户回答回答于

访问控制器方法意味着从controller/link/scope访问父作用域上的方法。

如果指令是共享/继承父作用域,那么直接调用父作用域方法是非常直接的。

当你想从孤立的指令作用域访问父范围方法时,只需要做更多的工作。

很少有选项(可能比下面列出的更多)从孤立的指令作用域或监视父作用域变量调用父作用域方法(备选案文6特别是)。

我用的link function在这些示例中,但是你可以使用directive controller以及基于需求。

备选案文1。通过对象文字和指令html模板

index.html

<!DOCTYPE html>
<html ng-app="plunker">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="angular.js@1.3.x" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <p>Hello {{name}}!</p>

    <p> Directive Content</p>
    <sd-items-filter selected-items="selectedItems" selected-items-changed="selectedItemsChanged(selectedItems)" items="items"> </sd-items-filter>


    <P style="color:red">Selected Items (in parent controller) set to: {{selectedItemsReturnedFromDirective}} </p>

  </body>

</html>

itemfilterTemplate.html

<select ng-model="selectedItems" multiple="multiple" style="height: 200px; width: 250px;" ng-change="selectedItemsChanged({selectedItems:selectedItems})" ng-options="item.id as item.name group by item.model for item in items | orderBy:'name'">
  <option>--</option>
</select>

app.js

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

app.directive('sdItemsFilter', function() {
  return {
    restrict: 'E',
    scope: {
      items: '=',
      selectedItems: '=',
      selectedItemsChanged: '&'
    },
    templateUrl: "itemfilterTemplate.html"
  }
})

app.controller('MainCtrl', function($scope) {
  $scope.name = 'TARS';

  $scope.selectedItems = ["allItems"];

  $scope.selectedItemsChanged = function(selectedItems1) {
    $scope.selectedItemsReturnedFromDirective = selectedItems1;
  }

  $scope.items = [{
    "id": "allItems",
    "name": "All Items",
    "order": 0
  }, {
    "id": "CaseItem",
    "name": "Case Item",
    "model": "PredefinedModel"
  }, {
    "id": "Application",
    "name": "Application",
    "model": "Bank"
    }]

});

选项2.通过对象文字和指令链接/作用域

index.html

<!DOCTYPE html>
<html ng-app="plunker">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="angular.js@1.3.x" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <p>Hello {{name}}!</p>

    <p> Directive Content</p>
    <sd-items-filter selected-items="selectedItems" selected-items-changed="selectedItemsChanged(selectedItems)" items="items"> </sd-items-filter>


    <P style="color:red">Selected Items (in parent controller) set to: {{selectedItemsReturnedFromDirective}} </p>

  </body>

</html>

itemfilterTemplate.html

<select ng-model="selectedItems" multiple="multiple" style="height: 200px; width: 250px;" 
 ng-change="selectedItemsChangedDir()" ng-options="item.id as item.name group by item.model for item in items | orderBy:'name'">
  <option>--</option>
</select>

app.js

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

app.directive('sdItemsFilter', function() {
  return {
    restrict: 'E',
    scope: {
      items: '=',
      selectedItems: '=',
      selectedItemsChanged: '&'
    },
    templateUrl: "itemfilterTemplate.html",
    link: function (scope, element, attrs){
      scope.selectedItemsChangedDir = function(){
        scope.selectedItemsChanged({selectedItems:scope.selectedItems});  
      }
    }
  }
})

app.controller('MainCtrl', function($scope) {
  $scope.name = 'TARS';

  $scope.selectedItems = ["allItems"];

  $scope.selectedItemsChanged = function(selectedItems1) {
    $scope.selectedItemsReturnedFromDirective = selectedItems1;
  }

  $scope.items = [{
    "id": "allItems",
    "name": "All Items",
    "order": 0
  }, {
    "id": "CaseItem",
    "name": "Case Item",
    "model": "PredefinedModel"
  }, {
    "id": "Application",
    "name": "Application",
    "model": "Bank"
    }]
});

选项3.通过函数引用和指令html模板

index.html

<!DOCTYPE html>
<html ng-app="plunker">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="angular.js@1.3.x" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <p>Hello {{name}}!</p>

    <p> Directive Content</p>
    <sd-items-filter selected-items="selectedItems" selected-items-changed="selectedItemsChanged" items="items"> </sd-items-filter>


    <P style="color:red">Selected Items (in parent controller) set to: {{selectedItemsReturnFromDirective}} </p>

  </body>

</html>

itemfilterTemplate.html

<select ng-model="selectedItems" multiple="multiple" style="height: 200px; width: 250px;" 
 ng-change="selectedItemsChanged()(selectedItems)" ng-options="item.id as item.name group by item.model for item in items | orderBy:'name'">
  <option>--</option>
</select>

app.js

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

app.directive('sdItemsFilter', function() {
  return {
    restrict: 'E',
    scope: {
      items: '=',
      selectedItems:'=',
      selectedItemsChanged: '&'
    },
    templateUrl: "itemfilterTemplate.html"
  }
})

app.controller('MainCtrl', function($scope) {
  $scope.name = 'TARS';

  $scope.selectedItems = ["allItems"];

  $scope.selectedItemsChanged = function(selectedItems1) {
    $scope.selectedItemsReturnFromDirective = selectedItems1;
  }

  $scope.items = [{
    "id": "allItems",
    "name": "All Items",
    "order": 0
  }, {
    "id": "CaseItem",
    "name": "Case Item",
    "model": "PredefinedModel"
  }, {
    "id": "Application",
    "name": "Application",
    "model": "Bank"
    }]
});

选项4.通过函数引用和指令链接/作用域

index.html

<!DOCTYPE html>
<html ng-app="plunker">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="angular.js@1.3.x" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <p>Hello {{name}}!</p>

    <p> Directive Content</p>
    <sd-items-filter selected-items="selectedItems" selected-items-changed="selectedItemsChanged" items="items"> </sd-items-filter>


    <P style="color:red">Selected Items (in parent controller) set to: {{selectedItemsReturnedFromDirective}} </p>

  </body>

</html>

itemfilterTemplate.html

<select ng-model="selectedItems" multiple="multiple" style="height: 200px; width: 250px;" ng-change="selectedItemsChangedDir()" ng-options="item.id as item.name group by item.model for item in items | orderBy:'name'">
  <option>--</option>
</select>

app.js

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

app.directive('sdItemsFilter', function() {
  return {
    restrict: 'E',
    scope: {
      items: '=',
      selectedItems: '=',
      selectedItemsChanged: '&'
    },
    templateUrl: "itemfilterTemplate.html",
    link: function (scope, element, attrs){
      scope.selectedItemsChangedDir = function(){
        scope.selectedItemsChanged()(scope.selectedItems);  
      }
    }
  }
})

app.controller('MainCtrl', function($scope) {
  $scope.name = 'TARS';

  $scope.selectedItems = ["allItems"];

  $scope.selectedItemsChanged = function(selectedItems1) {
    $scope.selectedItemsReturnedFromDirective = selectedItems1;
  }

  $scope.items = [{
    "id": "allItems",
    "name": "All Items",
    "order": 0
  }, {
    "id": "CaseItem",
    "name": "Case Item",
    "model": "PredefinedModel"
  }, {
    "id": "Application",
    "name": "Application",
    "model": "Bank"
    }]

});

选项5:通过ng模型和双向绑定,您可以更新父作用域变量。因此,在某些情况下,你可能不需要调用父作用域函数。

index.html

<!DOCTYPE html>
<html ng-app="plunker">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="angular.js@1.3.x" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <p>Hello {{name}}!</p>

    <p> Directive Content</p>
    <sd-items-filter ng-model="selectedItems" selected-items-changed="selectedItemsChanged" items="items"> </sd-items-filter>


    <P style="color:red">Selected Items (in parent controller) set to: {{selectedItems}} </p>

  </body>

</html>

itemfilterTemplate.html

<select ng-model="selectedItems" multiple="multiple" style="height: 200px; width: 250px;" 
 ng-options="item.id as item.name group by item.model for item in items | orderBy:'name'">
  <option>--</option>
</select>

app.js

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

app.directive('sdItemsFilter', function() {
  return {
    restrict: 'E',
    scope: {
      items: '=',
      selectedItems: '=ngModel'
    },
    templateUrl: "itemfilterTemplate.html"
  }
})

app.controller('MainCtrl', function($scope) {
  $scope.name = 'TARS';

  $scope.selectedItems = ["allItems"];

  $scope.items = [{
    "id": "allItems",
    "name": "All Items",
    "order": 0
  }, {
    "id": "CaseItem",
    "name": "Case Item",
    "model": "PredefinedModel"
  }, {
    "id": "Application",
    "name": "Application",
    "model": "Bank"
    }]
});

备选案文6:贯穿$watch$watchCollection它是双向绑定的items在上述所有示例中,如果在父作用域中修改了项,指令中的项也将反映更改。

如果希望从父作用域查看其他属性或对象,可以使用$watch$watchCollection如下所示

HTML

<!DOCTYPE html>
<html ng-app="plunker">

<head>
  <meta charset="utf-8" />
  <title>AngularJS Plunker</title>
  <script>
    document.write('<base href="' + document.location + '" />');
  </script>
  <link rel="stylesheet" href="style.css" />
  <script data-require="angular.js@1.3.x" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
  <script src="app.js"></script>
</head>

<body ng-controller="MainCtrl">
  <p>Hello {{user}}!</p>
  <p>directive is watching name and current item</p>
  <table>
    <tr>
      <td>Id:</td>
      <td>
        <input type="text" ng-model="id" />
      </td>
    </tr>
    <tr>
      <td>Name:</td>
      <td>
        <input type="text" ng-model="name" />
      </td>
    </tr>
    <tr>
      <td>Model:</td>
      <td>
        <input type="text" ng-model="model" />
      </td>
    </tr>
  </table>

  <button style="margin-left:50px" type="buttun" ng-click="addItem()">Add Item</button>

  <p>Directive Contents</p>
  <sd-items-filter ng-model="selectedItems" current-item="currentItem" name="{{name}}" selected-items-changed="selectedItemsChanged" items="items"></sd-items-filter>

  <P style="color:red">Selected Items (in parent controller) set to: {{selectedItems}}</p>
</body>

</html>

script app.js

var app=angular.Module(“plunker”),[]);

app.directive('sdItemsFilter', function() {
  return {
    restrict: 'E',
    scope: {
      name: '@',
      currentItem: '=',
      items: '=',
      selectedItems: '=ngModel'
    },
    template: '<select ng-model="selectedItems" multiple="multiple" style="height: 140px; width: 250px;"' +
      'ng-options="item.id as item.name group by item.model for item in items | orderBy:\'name\'">' +
      '<option>--</option> </select>',
    link: function(scope, element, attrs) {
      scope.$watchCollection('currentItem', function() {
        console.log(JSON.stringify(scope.currentItem));
      });
      scope.$watch('name', function() {
        console.log(JSON.stringify(scope.name));
      });
    }
  }
})

 app.controller('MainCtrl', function($scope) {
  $scope.user = 'World';

  $scope.addItem = function() {
    $scope.items.push({
      id: $scope.id,
      name: $scope.name,
      model: $scope.model
    });
    $scope.currentItem = {};
    $scope.currentItem.id = $scope.id;
    $scope.currentItem.name = $scope.name;
    $scope.currentItem.model = $scope.model;
  }

  $scope.selectedItems = ["allItems"];

  $scope.items = [{
    "id": "allItems",
    "name": "All Items",
    "order": 0
  }, {
    "id": "CaseItem",
    "name": "Case Item",
    "model": "PredefinedModel"
  }, {
    "id": "Application",
    "name": "Application",
    "model": "Bank"
  }]
});

你可以随时查阅AngularJ的文档,以获得有关指令的详细说明。

热门问答

域名注册时写了企业,可以转为个人的吗?

滑稽园扛把子

Swoole · PHP开发工程师 (已认证)

As a PHP Developer
推荐
可以的,操作如下 登录控制台 登录 腾讯云控制台。 选择 “云产品 > 域名与网站 > 域名注册”,进入 “域名服务” 页面,查看已购买的所有域名信息。 修改/过户域名信息 在需要修改域名信息的域名行中,单击【更多】,选择【域名信息修改】。如下图所示: 也可直接单击需要修改域名信...... 展开详请

如何按照上传时间顺序,获取cos bucket 中的object信息?

波斯狗儿对象存储产品经理
推荐
对象存储是 KV 有序存储,只能按对象键 UTF-8 字符顺序排。详细了解对象的概念:https://cloud.tencent.com/document/product/436/13324 如果需要按时间列表,需要在上传时就指定好路径,这样列表的时候也是按顺序的。比如 pho...... 展开详请

云开发环境和开发者自己的服务器能连通吗?

李成熙heyli

腾讯 · 高级工程师 (已认证)

腾讯高级工程师,专注于工程化及性能优化。 https://github.com/lcxfs1991
可以的请参考这份教程: https://github.com/TencentCloudBase/mp-book/blob/master/guide/readme.md#3-%E5%9C%A8%E8%87%AA%E5%B7%B1%E7%9A%84%E6%9C%8D%E5%8A%A1...... 展开详请

腾讯云 COS 怎么才能外链调用 m3u8 到别的网站播放?

滑稽园扛把子

Swoole · PHP开发工程师 (已认证)

As a PHP Developer
推荐
设置公有读私有写:当访问对象时,COS 读取到对象的权限为公有读,此时无论存储桶为何种权限,对象都可以被直接下载 设置步骤 登录 对象存储控制台,选择左侧菜单栏【存储桶列表】,进入存储桶列表页面。单击需要修改对象权限的对应存储桶,进入存储桶。 📷 找到需要设置权限的对象(如 e...... 展开详请

云通信IM 可以发送语音消息吗?

YingJoy_腾讯云+校园合伙人
可以的哦,在云通信IM的文档中有写 消息类型(文本,图片,语音,表情等自定义消息): 文本:最大 1~2k 字节(支持透传特殊字符); 图片:原图/缩略图/大图(支持格式:png/gif/jpeg/jpg/webp); 语音:异步语音消息(语音支持暂无上限); 表情等自定义消息...... 展开详请

Ubuntu搭建的WordPress如何修改php.ini?

滑稽园扛把子

Swoole · PHP开发工程师 (已认证)

As a PHP Developer
推荐
php新手很多不知道怎么查配置文件在哪,这里提供一个很简单的方法 使用 php -i 命令可以打印php的详细信息,可以把这堆东西输出一下 php -i > outputphp.txt,结合 grep 查找命令 php -i| grep php.ini 打印结果如下 Config...... 展开详请

所属标签

扫码关注云+社区