如何从AngularJS中具有自己的范围*的自定义指令*中访问父作用域?

时间:2013-07-27 16:47:58

标签: angularjs angularjs-directive

我正在寻找在指令中访问“父”范围的任何方式。范围,转换,要求的任何组合,从上面传递变量(或范围本身)等。我完全愿意向后弯腰,但我想避免一些完全hacky或不可维护的东西。例如,我知道我现在可以通过从preLink参数中取$scope并迭代它的$sibling范围来找到概念性的“父”。

我真正想要的是能够$watch父范围内的表达式。如果我能做到这一点,那么我可以完成我在这里要做的事情: AngularJS - How to render a partial with variables?

重要提示是指令必须可在同一父范围内重复使用。因此默认行为(范围:false)对我不起作用。我需要每个指令实例有一个单独的范围,然后我需要$watch一个存在于父范围内的变量。

代码示例值1000字,所以:

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?
                }
            }
        }
    };
});

6 个答案:

答案 0 :(得分:626)

请参阅What are the nuances of scope prototypal / prototypical inheritance in AngularJS?

总结:指令访问其父($parent)范围的方式取决于指令创建的范围类型:

  1. default(scope: false) - 该指令不会创建新范围,因此这里没有继承。该指令的作用域与父/容器的作用域相同。在链接功能中,使用第一个参数(通常为scope)。

  2. scope: true - 该指令创建一个新的子范围,该范围原型继承自父范围。在父作用域上定义的属性可用于指令scope(因为原型继承)。只要注意写入原始范围属性 - 这将在指令范围上创建一个新属性(隐藏/隐藏同名父范围属性)。

  3. scope: { ... } - 该指令创建一个新的隔离/隔离范围。它没有原型继承父作用域。您仍然可以使用$parent访问父作用域,但通常不建议这样做。相反,您应该使用=@和{{1}指定使用该指令的同一元素上的附加属性指定指令所需的父作用域属性(和/或函数)。记谱法。

  4. & - 该指令创建一个新的“transcluded”子作用域,它原型继承自父作用域。如果该指令还创建了隔离范围,则transcluded和隔离范围是兄弟。每个范围的transclude: true属性引用相同的父范围。
    Angular v1.3 update :如果该指令还创建了隔离范围,则转换范围现在是子范围隔离范围。被抄袭和隔离的范围不再是兄弟姐妹。现在,transcluded范围的$parent属性引用了隔离范围。

  5. 以上链接包含所有4种类型的示例和图片。

    您无法访问指令编译函数中的作用域(如此处所述:https://github.com/angular/angular.js/wiki/Understanding-Directives)。您可以在链接函数中访问指令的范围。

    <强>观赏:

    对于1.和2.上面:通常你通过一个属性指定指令需要哪个父属性,然后$ watch it:

    $parent

    <div my-dir attr1="prop1"></div>
    

    如果您正在观看对象属性,则需要使用$ parse:

    scope.$watch(attrs.attr1, function() { ... });
    

    <div my-dir attr2="obj.prop2"></div>
    

    对于3. above(隔离范围),请使用var model = $parse(attrs.attr2); scope.$watch(model, function() { ... }); @表示法查看您为其指定属性的名称:

    =

    <div my-dir attr3="{{prop3}}" attr4="obj.prop4"></div>
    

答案 1 :(得分:49)

访问控制器方法意味着从指令控制器/链接/范围访问父作用域上的方法。

如果指令是共享/继承父作用域,则只需调用父作用域方法就可以了。

如果要从Isolated指令范围访问父作用域方法,则需要做更多的工作。

从隔离指令范围调用父作用域方法或监视父作用域变量(选项#6 ),几乎没有选项(可能超出下面列出的选项)。

注意我在这些示例中使用了link function,但您也可以根据要求使用directive controller

选项#1。 通过对象文字和指令html模板

<强> 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>

<强> 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>

<强> 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"
    }]

});

work plnkr:http://plnkr.co/edit/rgKUsYGDo9O3tewL6xgr?p=preview

选项#2。通过Object文字和指令链接/范围

<强> 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>

<强> 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>

<强> 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"
    }]
});

work plnkr:http://plnkr.co/edit/BRvYm2SpSpBK9uxNIcTa?p=preview

选项#3。通过函数参考和指令html模板

<强> 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>

<强> 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>

<强> 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"
    }]
});

work plnkr:http://plnkr.co/edit/Jo6FcYfVXCCg3vH42BIz?p=preview

选项#4。通过函数参考和指令链接/范围

<强> 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>

<强> 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>

<强> 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"
    }]

});

work plnkr:http://plnkr.co/edit/BSqx2J1yCY86IJwAnQF1?p=preview

选项#5:通过ng-model和双向绑定,您可以更新父范围变量。。因此,在某些情况下,您可能不需要调用父作用域函数。

<强> 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>

<强> 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>

<强> 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"
    }]
});

work plnkr:http://plnkr.co/edit/hNui3xgzdTnfcdzljihY?p=preview

选项#6:通过$watch$watchCollection 在上述所有示例中,items都是双向绑定,如果在父作用域中修改了项目,则指令中的项目也会反映这些更改。

如果您想观看父作用域中的其他属性或对象,可以使用$watch$watchCollection执行此操作,如下所示

<强> 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>

脚本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"
  }]
});

您可以随时参考AngularJs文档,以获取有关指令的详细说明。

答案 2 :(得分:11)

 scope: false
 transclude: false

你将拥有相同的范围(使用父元素)

$scope.$watch(...

有很多方法可以访问父作用域取决于这两个选项范围&amp; transclude。

答案 3 :(得分:7)

这是我曾经使用过的一个技巧:创建一个“虚拟”指令来保存父作用域并将其放在所需指令之外的某个位置。类似的东西:

module.directive('myDirectiveContainer', function () {
    return {
        controller: function ($scope) {
            this.scope = $scope;
        }
    };
});

module.directive('myDirective', function () {
    return {
        require: '^myDirectiveContainer',
        link: function (scope, element, attrs, containerController) {
            // use containerController.scope here...
        }
    };
});

然后

<div my-directive-container="">
    <div my-directive="">
    </div>
</div>

也许不是最优雅的解决方案,但它完成了工作。

答案 4 :(得分:4)

如果您使用的是ES6 Classes和ControllerAs语法,则需要做一些稍微不同的事情。

请参阅下面的代码段并注意vm是父HTML中使用的父控制器的ControllerAs

myApp.directive('name', function() {
  return {
    // no scope definition
    link : function(scope, element, attrs, ngModel) {

        scope.vm.func(...)

答案 5 :(得分:0)

尝试了一切后,我终于找到了解决方案。

只需将以下内容放入模板中即可:

{{currentDirective.attr = parentDirective.attr; ''}}

它只是写入您要访问当前范围的父范围属性/变量。

还要注意语句末尾的; '',以确保模板中没有输出。 (Angular评估每个语句,但仅输出最后一个语句。)

有点hacky,但经过几个小时的反复试验后,它就完成了工作。