AngularJS多个动态指令绑定

我是AngularJS的新手，我太笨了，无法让它工作。

我正在尝试生成

• 面板列表（动态）
• 当我单击面板标题时，面板主体将展开/折叠
• 当特定的面板主体折叠时，我想创建一个表并将一些数据绑定到其中

这是我的代码

    <script>
    var app = angular.module('TestApp', []);
    app.controller('TestCtrl', function ($scope) {
        $scope.parents = [
            { id: '1', name: 'Test Parent 1', count: '2' },
            { id: '2', name: 'Test Parent 2', count: '3' },
            { id: '3', name: 'Test Parent 3', count: '1' }
        ];
        $scope.parent_click = function (parent) {
            var children_list = [
            { id: '1', parent_id: '1', name: 'Test Child 1' },
            { id: '2', parent_id: '1', name: 'Test Child 2' },
            { id: '3', parent_id: '2', name: 'Test Child 3' },
            { id: '4', parent_id: '2', name: 'Test Child 4' },
            { id: '5', parent_id: '2', name: 'Test Child 5' },
            { id: '6', parent_id: '3', name: 'Test Child 6' }
            ];
            var directive_name = 'clschild_' + parent.id;
            app.directive(directive_name, function () {
                var child_html = '<div class="panel-body"> '
                    <table ng-attr-id="tblchild_'+ parent.id + '" class="table table-hover"> '
                        <thead> '
                            <tr> '
                                <td>Name</td> '
                            </tr> '
                        </thead> '
                        <tbody> '
                            <tr ng-repeat="child in children"> '
                                <td>{{child.name}}</td> '
                            </tr> '
                        </tbody> '
                    </table> '
                </div>';
                return {
                    template: child_html,
                    link: function (scope) {
                        scope.$apply(function () { scope.children = children_list; });
                    }
                }
            });
        };
    });
</script>
<div ng-app="TestApp" ng-controller="TestCtrl">
    <div class="panel panel-default" ng-repeat="parent in parents">
        <div class="panel-heading clearfix">
            <a id="testtest" data-toggle="collapse" ng-href="#divchild_{{parent.id}}" ng-click="parent_click(parent);" class="pull-left" style="padding-top: 7.5px;">{{parent.name}}</a>
        </div>
        <div ng-attr-id="divchild_{{parent.id}}" class="panel-collapse collapse">
            <div class="clschild_{{parent.id}}">
                <div class="panel-body">
                    aaa
                </div>
            </div>
        </div>
    </div>
</div>

我想将数据绑定到相应父级的面板主体。我怎样才能做到这一点？

编辑：问题-现在，当我点击面板标题时，面板主体展开，但只显示"aaa"。我无法将子列表绑定到面板主体。

感谢