angularjs - angularjs范围在指令中不可访问

Question

我正在尝试使用 angularjs 指令加载图表。我想在数据来自服务器响应后加载图表。但是范围是空的。我的代码是

<div class="span4" ui-if="loadingIsDone">
                                            <article id="piChart2">
                                                <section id="toolBox1">
                                                    <h3 id="toolH1"></h3>
                                                    <p id="toolD1"></p>
                                                </section>
                                                <article id="toolTip1"></article>
                                                <canvas id="canvas1" width="250" height="250" draw-chart>

                                                </canvas>
                                            </article>
                                        </div>

我的控制器是

controller(){
 $scope.teamStrengths =  {};
 $scope.loadingIsDone = false;

 $http({
        url: "url", 
          method: "POST",
          data: {"userUids":uids}
         }).success(function(response){

             $scope.teamStrengths =  response.resource.strengths;//data loads successfully


             $scope.loadingIsDone = true;

             //rest of code is skipped
}

我的指令是

Directives.directive('drawChart', function() {
       return function(scope, element, attrs) {

           console.debug("element :"+element);
           console.debug("attrs :"+attrs);

             graphDraw('canvas1',scope.teamStrengths.value1,scope.teamStrengths.value2,scope.teamStrengths.value3)
         //grap loads successfully with static data



       };
     });

请帮助我，我将不胜感激

Answer 1

$http调用是异步的。指令需要$watch在scope. 在你的指令中添加这个：

 scope.$watch('teamStrengths', function(newValue, oldValue) {
     if (newValue)
        graphDraw('canvas1',scope.teamStrengths.value1,scope.teamStrengths.value2,scope.teamStrengths.value3)
 }, true);

或注意$scope.loadingIsDone变化：

 scope.$watch('loadingIsDone', function(newValue, oldValue) {
     if (newValue == true)
        graphDraw('canvas1',scope.teamStrengths.value1,scope.teamStrengths.value2,scope.teamStrengths.value3)
 }, true);