amcharts使用心得

在使用amcharts做统计的时候，遇到一个问题，就是怎么把后台传过来的一个json格式的字符串怎么转换成json数组，因为amchatrs要求解析的数据格式是json格式的数组。

解决方案：在js中先将隐藏域中的值转换成Array数组，再赋给chart的dataProvider属性，具体过程如下：

1、action中需要一个变量存储json格式的字符串传到jsp页面。

private String countAllStr = "";

public String getCountAllStr() {   

　　return countAllStr;  

}

public void setCountAllStr(String countAllStr) {   

　　this.countAllStr = countAllStr;

}

2、jsp页面处理：

<input id="countAllStr" type="hidden" value="<s:property value='countAllStr'/>"/>

<script type="text/javascript">  

　　var dataForCountAll = new Array();
  　 dataForCountAll = eval($("#countAllStr").val());

　　// SERIAL CHART
     var chartForCountAll = new AmCharts.AmSerialChart();
     chartForCountAll.dataProvider = dataForCountAll;
     chartForCountAll.categoryField = "title";
     chartForCountAll.marginRight = 0;
     chartForCountAll.marginTop = 0;   
     chartForCountAll.autoMarginOffset = 0;
     chartForCountAll.columnWith = 5;
   // the following two lines makes chart 3D
     chartForCountAll.depth3D = 20;
     chartForCountAll.angle = 30;
     //columnWidth
     chartForCountAll.columnWidth = 0.2;
     //columnSpacing
     chartForCountAll.columnSpacing = 2;
     //colors
     //chartForCountAll.colors = ['#FF6600', '#FCD202', '#B0DE09', '#0D8ECF', '#2A0CD0', '#CD0D74', '#CC0000', '#00CC00', '#0000CC', '#DDDDDD', '#999999', '#333333', '#990000'];
     // category
     var categoryAxis = chartForCountAll.categoryAxis;
     categoryAxis.labelRotation = 0;
     categoryAxis.dashLength = 5;
     categoryAxis.gridPosition = "start";
     // value
     var valueAxis = new AmCharts.ValueAxis();
     valueAxis.dashLength = 5;
     chartForCountAll.addValueAxis(valueAxis);
     // GRAPH           
     var graph = new AmCharts.AmGraph();
     graph.valueField = "value";
     graph.balloonText = "[[title]]: [[value]]";
     graph.type = "column";
     graph.lineAlpha = 0;
     graph.fillAlphas = 1;
     graph.lineColor = ['#FF6600', '#FCD202'];
     chartForCountAll.addGraph(graph);
     // WRITE
     chartForCountAll.write("countAllList");

</script>