FusionCharts ajax 调用方式

方式一:setJSONUrl

function initChart() {
                    var myChart = new FusionCharts("FusionCharts/Line.swf", "myChartId", "100%", "100%", "0", "1");
                    var url = '${pageContext.request.contextPath}/enterleaveinfoAction!realtimeCarEnterinfoChart.action?carDate=2013-0=11-28';
                    myChart.setJSONUrl(url);                 
                    myChart.render("chartContainer");
                }

问题：第一次页面加载没问题，后续刷新时会出现 no data to display，据说是跟渲染没完成重新请求数据有关。

方式二:setJSONData

 function initChart() {
            $.ajax({
                type: "POST",
                contentType: "application/json; charset=utf-8",
                url: "${pageContext.request.contextPath}/enterleaveinfoAction!realtimeCarEnterinfoChart.action?carDate=2013-0=11-28",
                data: "{}",
                dataType: 'json',

                success: function (json) {
                    var myChart = new FusionCharts("FusionCharts/Line.swf", "myChartId", "100%", "100%", "0", "1");
                    myChart.setJSONData(json);
                    myChart.render("chartContainer");
                },

                error: function (xhr) { //如果没有上面的捕获出错会执行这里的回调函数
                    alert('页出错\n\r' + xhr.responseText);
                }

            });
        }