javascript - Amcharts:更改整个数据集

Question

我开始使用 amcharts 4，但遇到了问题:根据文档更改图表数据集，只需将新的对象数组分配给 chart.data:

chart.data = [{ some data object }, {}......]

它似乎对我有用，请参阅此代码笔:https://codepen.io/anon/pen/LMgEjV

/**
 * ---------------------------------------
 * This demo was created using amCharts 4.
 *
 * For more information visit:
 * https://www.amcharts.com/
 *
 * Documentation is available at:
 * https://www.amcharts.com/docs/v4/
 * ---------------------------------------
 */

// Create chart instance
var chart = am4core.create("chartdiv", am4charts.PieChart);

// Add data
chart.data = [{
  "country": "Lithuania",
  "litres": 501.9
}, {
  "country": "Czech Republic",
  "litres": 301.9
}, {
  "country": "Ireland",
  "litres": 201.1
}, {
  "country": "Germany",
  "litres": 165.8
}, {
  "country": "Australia",
  "litres": 139.9
}, {
  "country": "Austria",
  "litres": 128.3
}, {
  "country": "UK",
  "litres": 99
}, {
  "country": "Belgium",
  "litres": 60
}, {
  "country": "The Netherlands",
  "litres": 50
}];

// Add and configure Series
var pieSeries = chart.series.push(new am4charts.PieSeries());
pieSeries.dataFields.value = "litres";
pieSeries.dataFields.category = "country";

function changeData() {
  chart.data = [{
    "country": "Lithuania",
    "litres": 501.9
   }, {
      "country": "Czech Republic",
      "litres": 301.9
    }
  ];
  
  chart.validateData();
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
}

#chartdiv {
  width: 100%;
  height: 400px;
}

<script src="https://www.amcharts.com/lib/4/core.js"></script>
<script src="https://www.amcharts.com/lib/4/charts.js"></script>
<button id="btn-change" onClick="changeData()">Click Me</button>
<div id="chartdiv"></div>

我错过了什么？

Answer 1

我不是 100% 确定我理解问题，但无论如何我会尽力帮助你，我检查了你的代码，我认为主要问题发生了，因为你将整个数组推送到 chart.data而不仅仅是您要更改的对象。请看我的代码:

function changeData() {
    chart.data.push({
        "country": "Lithuania",
        "litres": "501.9"
       })

 chart.validateData();
}