javascript - 如何从 AngularJS 指令中选择动态生成的元素？

Question

在我的指令中，我需要选择某些 DOM 元素，其中一些元素是在 ng-repeat 循环中动态生成的。如果我以直接的方式进行，我只会得到静态元素。但是，如果我将选择延迟 500 毫秒，我将获得所有元素，这正是我想要的。

虽然这可行，但它不是一个理想的解决方案，而且看起来肯定不是最佳实践。一方面，您希望超时时间尽可能短，但另一方面，您希望在选择之前确保 DOM 已准备就绪。

当所有动态 DOM 准备就绪时，是否会触发一个事件？从 AngularJS 指令中选择动态生成的元素的推荐方法是什么？

示例:

HTML:

<div data-my-directive>
    <div class="modal-body">                        
        <label data-localize>type:</label>&nbsp;
        <select class="form-control" ng-model="assetFilter.appCode" ng-change="loadassets(assetFilter.appCode)" ng-options="type.code as type.name for type in types"></select>

            <table class="table table-default" ng-show="hasLoaded">
                <tbody ng-repeat="asset in assets | filter:assetFilter | orderBy:'assetKey':false">
                <tr>
                    <td>
                        <div class="container-fluid">
                            <div class="row vert-align">
                                <div class="col-sm-4">
                                    {{asset.assetKey}}
                                </div>
                                <div class="col-sm-8" style="height:100%">
                                    <input ng-hide="asset.assetKey.length >= 80" type="text" class="form-control" ng-model="asset.assetValue" ng-change="asset.isModified=true">
                                    <textarea ng-show="asset.assetKey.length > 80" class="form-control" ng-model="asset.assetValue" ng-change="asset.isModified=true"></textarea>
                                </div>
                            </div>
                        </div>
                    </td>
                </tr>
            </tbody>
        </table>

    </div>
    <div class="modal-footer">
        <button class="btn btn-primary" ng-click="save(saveassets, $event)" ng-disabled="!(assets | anyModified)" data-localize>Save</button>
        <button class="btn btn-warning" ng-click="close($event)" data-localize>Close</button>
    </div>
</div>

指令:

myApp.directive('myDirective', function ($timeout) {
    return {
        restrict: 'A', //attribute only
        link: function (scope, elem, attr, ctrl) {    
            var context = elem[0]; 
            var availableFormElements = 'input:not([disabled]):not([class*=ng-hide]),' +
                'select:not([disabled]):not([class*=ng-hide]), textarea:not([disabled]):not([class*=ng-hide]),' +
                'button:not([disabled]):not([class*=ng-hide]),' +
                '*[class*=btn]:not([disabled]):not([class*=ng-hide])';

            var allFormElements = context.querySelectorAll(availableFormElements);
            // Will only get static elements, nothing from ng-repeat loop

            $timeout(function () {
                allFormElements = context.querySelectorAll(availableFormElements);
                // Will include all elements, also from ng-repeat loop
            }, 500);     

            // Code to manipulate selected form elements   

    };
});

Answer 1

这是一个简单的示例，您可以如何计算它。Imo 这个解决方案的唯一缺点是你不能使用隔离范围。

html

<div data-ng-controller="MainController">
    <div outer-directive>
        <ul>
            <li ng-repeat="asset in assets" inner-directive>
                      {{asset}}
                      <input type="text" class="form-control">
            </li>
        </ul>
    </div>
</div>

js

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

app.controller('MainController',function($scope) {
    $scope.assets = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20]; 
});

app.directive('outerDirective', function() {
  return {
    restrict: 'A',
    controller: function($scope) {

    }
  };
});
app.directive('innerDirective', function() {
  return {
    restrict: 'A',
    require: '^outerDirective',
    link: function(scope, elem, attrs,ctrl) {
        var context = elem[0]; 
        if (scope.$last){
            var availableFormElements = 'input,textarea';
            var allFormElements = context.querySelectorAll(availableFormElements);
            console.log(allFormElements);
        }
    }
  };
});

或更好

.directive('myParent', function ($timeout) {
        return {
            restrict: 'A', //attribute only
            controller: function ($scope, $element) { 
                this.isDone = function(){
                    var context = $element[0]; 
                    var availableFormElements = 'input,textarea';
                    var allFormElements = context.querySelectorAll(availableFormElements);
                    console.log(allFormElements);
                }
            }
        };
    })
    .directive('myChild', function ($timeout) {
        return {
            require:'^myParent',
            restrict: 'A', //attribute only
            link: function (scope, elem, attr, ctrl) {    

                if (scope.$last){
                    ctrl.isDone();
                }
            }
        };
    })

顺便说一下不要触摸 Controller 中的 dom :)