指令中不可访问angularjs范围

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，我将非常感谢（

$http

呼叫是异步的。指令需要在

范围内
$watch
更改。在指令中添加以下内容：

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

或监视
$scope.LoadingIsOne
更改：

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

$http
调用是异步的。指令需要在
范围内
$watch
更改。在指令中添加以下内容：

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

或监视
$scope.LoadingIsOne
更改：

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