使用 ajax 从 chartjs 填充动态饼图

Question

你好堆栈溢出程序员，我有一个关于使用 ajax 从我的数据库中获取数据并将其显示在 chartjs 库中的饼图中的问题。现在我正在尝试使动态数据被饼图格式中的格式所接受。

这是我的 ajax 及其响应：（仍然没有显示我的 piegraph。我不知道为什么）

    function getpieclinic() {
    $.ajax({
            type: "POST",
            url: siteurl+"patients_report/piedataclinic",
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: OnSuccess_,
            error: OnErrorCall_
    });

    function OnSuccess_(response) {
      // alert("hi");
            var aData = response.d;
            var arr = [];
            $.each(aData, function (inx, val) {
                var obj = {};
                obj.color = val.color;
                obj.value = val.value;
                obj.label = val.label;
                arr.push(obj);
            });
            var ctx = $("#myChart").get(0).getContext("2d");
            var myPieChart = new Chart(ctx).Pie(arr);
        }

        function OnErrorCall_(response) {}
}

我的 ajax 响应如下：

[{"clinic_name":"Clinic 1","total_checked_up":"4"},{"clinic_name":"Clinic 2","total_checked_up":"0"},{"clinic_name":"Clinic 3","total_checked_up":"0"},{"clinic_name":"Clinic 4","total_checked_up":"0"}]

现在，我想制作饼图chartjs 数据格式的动态格式，以便能够显示它。这是示例中的默认格式：

var pieChartCanvas = $("#pieChart").get(0).getContext("2d");
    var pieChart = new Chart(pieChartCanvas);
    var PieData = [
      {
        value: 700,
        color: "#f56954",
        highlight: "#f56954",
        label: "Chrome"
      },
      {
        value: 500,
        color: "#00a65a",
        highlight: "#00a65a",
        label: "IE"
      },
      {
        value: 400,
        color: "#f39c12",
        highlight: "#f39c12",
        label: "FireFox"
      },
      {
        value: 600,
        color: "#00c0ef",
        highlight: "#00c0ef",
        label: "Safari"
      },
      {
        value: 300,
        color: "#3c8dbc",
        highlight: "#3c8dbc",
        label: "Opera"
      },
      {
        value: 100,
        color: "#d2d6de",
        highlight: "#d2d6de",
        label: "Navigator"
      }
    ];
    var pieOptions = {
      //Boolean - Whether we should show a stroke on each segment
      segmentShowStroke: true,
      //String - The colour of each segment stroke
      segmentStrokeColor: "#fff",
      //Number - The width of each segment stroke
      segmentStrokeWidth: 2,
      //Number - The percentage of the chart that we cut out of the middle
      percentageInnerCutout: 50, // This is 0 for Pie charts
      //Number - Amount of animation steps
      animationSteps: 100,
      //String - Animation easing effect
      animationEasing: "easeOutBounce",
      //Boolean - Whether we animate the rotation of the Doughnut
      animateRotate: true,
      //Boolean - Whether we animate scaling the Doughnut from the centre
      animateScale: false,
      //Boolean - whether to make the chart responsive to window resizing
      responsive: true,
      // Boolean - whether to maintain the starting aspect ratio or not when responsive, if set to false, will take up entire container
      maintainAspectRatio: true,
      //String - A legend template
      legendTemplate: "<ul class=\"<%=name.toLowerCase()%>-legend\"><% for (var i=0; i<segments.length; i++){%><li><span style=\"background-color:<%=segments[i].fillColor%>\"></span><%if(segments[i].label){%><%=segments[i].label%><%}%></li><%}%></ul>"
    };
    //Create pie or douhnut chart
    // You can switch between pie and douhnut using the method below.
    pieChart.Doughnut(PieData, pieOptions);

Answer 1

您可以通过以下方式完成此操作...

// for demonstration purposes only
// use response.d in real case scenario
var response = [{ "clinic_name": "Clinic 1", "total_checked_up": "10" }, { "clinic_name": "Clinic 2", "total_checked_up": "20" }, { "clinic_name": "Clinic 3", "total_checked_up": "30" }, { "clinic_name": "Clinic 4", "total_checked_up": "40" }]; // response from ajax request

OnSuccess_(response);

function OnSuccess_(response) {
    var pieChartCanvas = $("#pieChart").get(0).getContext("2d");
    var pieChart = new Chart(pieChartCanvas);
    var PieData = [];
  
    // create PieData dynamically
    response.forEach(function(e) {
        var random_color = '#' + Math.floor(Math.random() * 16777215).toString(16);
        PieData.push({
            value: e.total_checked_up,
            color: random_color,
            highlight: random_color,
            label: e.clinic_name
        });
    });
  
    var pieOptions = {
        //Boolean - Whether we should show a stroke on each segment
        segmentShowStroke: true,
        //String - The colour of each segment stroke
        segmentStrokeColor: "#fff",
        //Number - The width of each segment stroke
        segmentStrokeWidth: 2,
        //Number - The percentage of the chart that we cut out of the middle
        percentageInnerCutout: 0, // This is 0 for Pie charts
        //Number - Amount of animation steps
        animationSteps: 100,
        //String - Animation easing effect
        animationEasing: "easeOutBounce",
        //Boolean - Whether we animate the rotation of the Doughnut
        animateRotate: true,
        //Boolean - Whether we animate scaling the Doughnut from the centre
        animateScale: false,
        //Boolean - whether to make the chart responsive to window resizing
        responsive: true,
        // Boolean - whether to maintain the starting aspect ratio or not when responsive, if set to false, will take up entire container
        maintainAspectRatio: true,
        //String - A legend template
        legendTemplate: "<ul class=\"<%=name.toLowerCase()%>-legend\"><% for (var i=0; i<segments.length; i++){%><li><span style=\"background-color:<%=segments[i].fillColor%>\"></span><%if(segments[i].label){%><%=segments[i].label%><%}%></li><%}%></ul>"
    };
  
    //Create pie or douhnut chart
    // You can switch between pie and douhnut using the method below.
    pieChart.Doughnut(PieData, pieOptions);
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/1.0.2/Chart.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<canvas id="pieChart"></canvas>