chartjs动态创建数据数组 [英] chartjs creating data array dynamically

问题描述

我正在使用chartjs库创建一个饼图，并且想知道如何表示动态绘制图表所需要的值，

Im creating a Pie chart using chartjs library, and Im wondering how I could represent the values the will be need to render the chart dynamically,

在chartjs.org教程中，数据数组是这样表示的

In chartjs.org tutorial the array of data is represented like this

var data = [
        {
           value: 300,
           color:"#F7464A",
           highlight: "#FF5A5E",
           labelColor : 'white',
           labelFontSize : '16'
        },
        {
            value: 100,
            color: "#46BFBD",
            highlight: "#5AD3D1",           
            labelColor : 'white',
            labelFontSize : '16'
        },
        {
            value: 100,
            color: "#FDB45C",
            highlight: "#FFC870",
            labelColor : 'white',
            labelFontSize : '16'
        }
    ]

，数据将作为参数传递以呈现图表

and data will be pass as an argument to render the chart

new Chart(ctx).Pie(data);

然后呈现具有3个分区的图表:

this then renders a chart with 3 partitions:

但是说我想渲染X个分区，我该如何制作一个数据数组?

But say I want to render X partitions, how can i make an array of data?

我可以循环执行并将其附加到数据吗?

would I be able to do in a loop and append it to data?

到目前为止的代码:

function drawPie(ctx){

            var newopts = {
                inGraphDataShow: true,
                inGraphDataRadiusPosition: 2,
                inGraphDataFontColor: 'white',
            }

            //=========
            // this should be dynamic (data will come the parameter)
            //==========
            var data = [
            {
                value: 300,
                color:"#F7464A",
                highlight: "#FF5A5E",

                labelColor : 'white',
                 labelFontSize : '16'
            },
            {
                value: 100,
                color: "#46BFBD",
                highlight: "#5AD3D1",           

                labelColor : 'white',
                labelFontSize : '16'
            },
            {
                value: 100,
                color: "#FDB45C",
                highlight: "#FFC870",

                 labelColor : 'white',
                 labelFontSize : '16'
            }
        ]

        new Chart(ctx).Pie(data, newopts);

} 

推荐答案

您只需要按照Chart.js期望的饼状图生成数据结构，如果您不知道元素的最大数量，就可以生成饼图.颜色(如果您知道最大数量的元素，则可以从颜色数组中选择颜色).例如

You just need to generate the data structure in the way Chart.js expects for a pie chart and if you don't know the maximum number of element generate the colors (if you know the maximum number of elements, you could just pick it from a color array). For instance

var dynamicData = [
    { label: "One", value: 23 },
    { label: "Two", value: 33 },
    { label: "Three", value: 43 },
    { label: "Four", value: 53 },
]

dynamicData.forEach(function (e, i) {
    e.color = "hsl(" + (i / dynamicData.length * 360) + ", 50%, 50%)";
    e.highlight = "hsl(" + (i / dynamicData.length * 360) + ", 50%, 70%)";
    // + any other code you need to make your element into a chart.js pie element
})

var ctx = document.getElementById("myChart").getContext("2d");
var myPieChart = new Chart(ctx).Pie(dynamicData);

---

小提琴- http://jsfiddle.net/k4ztyqzc/

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