检测ng-repeat finish

$scope.data = [
    {
        str: 'a'
    },
    {
        str: 'b'
    },
    {
        str: 'c'
    }
]
//自定义指令repeatFinish
app.directive('repeatFinish',function(){
    return {
        link: function(scope,element,attr){
            console.log(scope.$index)
            if(scope.$last == true){
                console.log('ng-repeat执行完毕')
                scope.$eval( attr.repeatFinish );  // ng-repeat执行完毕后触发此函数
            }
        }
    }
})；
$scope.renderFinish = function(){
    console.log('渲染完之后的操作')
}
<div id="box">
    <span ng-repeat="item in data" repeat-finish="renderFinish()">{{item.str}}</span>
</div>