我没有显示D3饼图

Question

您好我正在尝试显示D3饼图，但我只获得图例符号...有人可以帮我显示动态数据显示的d3饼图。它不会显示任何错误只有图例符号显示饼图是没有显示。

这是我正在使用的html

    <script src="angularjs-nvd3-directives-master/examples/js/angular.js"></script>
    <script src="angularjs-nvd3-directives-master/examples/js/d3.js"></script>
    <script src="angularjs-nvd3-directives-master/examples/js/nv.d3.js"></script>
    <script src="angularjs-nvd3-directives-master/dist/angularjs-nvd3-directives.js"></script>

    <link href="angularjs-nvd3-directives-master/examples/stylesheets/nv.d3.css" rel="stylesheet" />

<style>
    #chart svg {
       height: 295px;
       width:300px;
    }
</style>
    <div id="chart">
       <svg></svg>
    </div>   

   and the javascript code i am using is...I want to display pie chart for dynamic data.


$.ajax({
        type: "POST",
        url: "Assets.asmx/Statereport",
        data: "{}",
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        success: OnSuccess

    });
    function OnSuccess(data, status) {

        var myObject = JSON.parse(data.d);
        var source = {
            datatype: "json",
            datafields: [
               { name: 'totsch' },
                { name: 'districtname' },
                { name: 'statename' }

            ],
            localdata: myObject
        };
        var dataAdapter = new $.jqx.dataAdapter(source);
        var ObjectIDs = [];
        for (var i = 0; i < myObject.length; i++) {
            ObjectIDs.push(myObject[i].statename);
        }
        var gridquerystr = ObjectIDs[0].toString();


    nv.addGraph(function () {
        var chart = nv.models.pieChart()
            .x(function (d) { return d.label })
            .y(function (d) { return d.value })
            .showLabels(false);

        d3.select("#chart svg")
            .datum(myObject)
          .transition().duration(1200)
            .call(chart);

        return chart;
    });

please help me as soon as posssible..... or suggest me any opensource charts for displaying dynamic data using ajax json data . I am new to coding so please help 
[![d3 pie chart][1]][1]


  [1]: http://i.stack.imgur.com/ppqZf.jpg