TreeMap是数据树的直观表示，其中每个节点可以有零个或多个子节点，以及一个父节点(根节点除外).每个节点都显示为一个矩形，可以根据我们指定的值进行调整大小和着色.尺寸和颜色相对于图中的所有其他节点进行估值.以下是树形图图表的示例.我们已经在 Google Charts Configuration Syntax 一章中看到了用于绘制此图表的配置.所以，让我们看一下完整的例子.
我们使用 TreeMap 类来显示树形图.
//TreeMap chart
var chart = new google.visualization.TreeMap(document.getElementById('container'));googlecharts_treemap.htm
<html>
<head>
<title>Google Charts Tutorial</title>
<script type = "text/javascript" src = "https://www.gstatic.com/charts/loader.js">
</script>
<script type = "text/javascript" src = "https://www.google.com/jsapi">
</script>
<script type = "text/javascript">
google.charts.load('current', {packages: ['treemap']});
</script>
</head>
<body>
<div id = "container" style = "width: 550px; height: 400px; margin: 0 auto">
</div>
<script language = "JavaScript">
function drawChart() {
// Define the chart to be drawn.
var data = new google.visualization.DataTable();
var data = google.visualization.arrayToDataTable([
['Location', 'Parent', 'Market trade volume (size)', 'Market increase/decrease (color)'],
['Global', null, 0, 0],
['America', 'Global', 0, 0],
['Europe', 'Global', 0, 0],
['Asia', 'Global', 0, 0],
['Australia', 'Global', 0, 0],
['Africa', 'Global', 0, 0],
['USA', 'America', 52, 31],
['Mexico', 'America', 24, 12],
['Canada', 'America', 16, -23],
['France', 'Europe', 42, -11],
['Germany', 'Europe', 31, -2],
['Sweden', 'Europe', 22, -13],
['China', 'Asia', 36, 4],
['Japan', 'Asia', 20, -12],
['India', 'Asia', 40, 63],
['Egypt', 'Africa', 21, 0],
['Congo', 'Africa', 10, 12],
['Zaire', 'Africa', 8, 10]
]);
var options = {
minColor: '#f00',
midColor: '#ddd',
maxColor: '#0d0',
headerHeight: 15,
fontColor: 'black',
showScale: true
};
// Instantiate and draw the chart.
var chart = new google.visualization.TreeMap(document.getElementById('container'));
chart.draw(data, options);
}
google.charts.setOnLoadCallback(drawChart);
</script>
</body>
</html>验证结果.
