我无法使用javascript在运行时更改amchart主题

Question

是否可以使用runtime在javascript更改图表主题？我无法在任何地方找到这样做的例子。

我尝试使用validateNow但没有成功。

谢谢！

Answer 1

如果要在运行时更改主题，则必须使用clear方法清除图表实例并重新创建图表。

这是一个例子：

var chart;
var chartConfig = {
  type: "serial",
  dataProvider: [{
    "year": 2005,
    "income": 23.5,
    "expenses": 18.1
  }, {
    "year": 2006,
    "income": 26.2,
    "expenses": 22.8
  }, {
    "year": 2007,
    "income": 30.1,
    "expenses": 23.9
  }, {
    "year": 2008,
    "income": 29.5,
    "expenses": 25.1
  }, {
    "year": 2009,
    "income": 24.6,
    "expenses": 25
  }],
  categoryField: "year",
  categoryAxis: {
    gridPosition: "start"
  },
  valueAxes: [{
    title: "Million USD"
  }],
  graphs: [{
    type: "column",
    title: "Income",
    valueField: "income",
    lineAlpha: 0,
    fillAlphas: 0.8,
    balloonText: "[[title]] in [[category]]:<b>[[value]]</b>"
  }, {
    type: "line",
    title: "Expenses",
    valueField: "expenses",
    lineThickness: 2,
    bullet: "round",
    balloonText: "[[title]] in [[category]]:<b>[[value]]</b>"
  }],
  legend: {
    useGraphSettings: true
  }
};

function createChart(theme) {      
  if (chart && chart.clear) {
    chart.clear();
  }
  var config = JSON.parse(JSON.stringify(chartConfig)); //clone the config before reusing it
  config.theme = theme;
  
  if (theme === "dark") {
    document.body.style.backgroundColor = "#282828";
  }
  else {
    document.body.style.backgroundColor = "#ffffff";
  }
  
  chart = AmCharts.makeChart("chartdiv", config);
}

//set up event handler for switching themes
Array.prototype.forEach.call(
  document.querySelectorAll("#theme-switch li"),
  function (li) {
    li.addEventListener("click", function() {
      createChart(li.id);
    });
  }
);


createChart("none");

#theme-switch li {
  display: inline;
  width: 10%;
  padding: 0 2em;
  border: 1px solid #ccc;
  color: #0000ff;
  cursor: pointer;
  background-color: #ececec;

}

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

<script type="text/javascript" src="//www.amcharts.com/lib/3/amcharts.js"></script>
<script type="text/javascript" src="//www.amcharts.com/lib/3/serial.js"></script>
<script type="text/javascript" src="//www.amcharts.com/lib/3/themes/none.js"></script>
<script type="text/javascript" src="//www.amcharts.com/lib/3/themes/light.js"></script>
<script type="text/javascript" src="//www.amcharts.com/lib/3/themes/dark.js"></script>

<ul id="theme-switch">
  <li id="none">None</li>
  <li id="light">Light</li>
  <li id="dark">Dark</li>
</ul>

<div id="chartdiv">
</div>