使用amCharts.js绘制柱形图（column chart）时，有时需要默认显示每一个柱子的数值。
通过在AmCharts.AmGraph中设置labelText属性为[[value]]，即可实现上述需求。
效果如下所示：
上例的代码如下所示：
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>amCharts examples</title> <link href="https://www.jb51.net/style.css" type="text/css"> <script src="https://www.amcharts.com/lib/3/amcharts.js" type="text/javascript"></script> <script src="https://www.amcharts.com/lib/3/serial.js" type="text/javascript"></script> <script src="https://www.amcharts.com/lib/3/themes/light.js"></script> <script> var chart; var chartData = [ { "country": "China", "visits": 2325 }, { "country": "USA", "visits": 1822 }, { "country": "Japan", "visits": 1809 }, { "country": "Germany", "visits": 1322 }, { "country": "UK", "visits": 1122 }, { "country": "France", "visits": 1114 } ]; AmCharts.ready(function () { // SERIAL CHART chart = new AmCharts.AmSerialChart(AmCharts.themes.light); chart.dataProvider = chartData; chart.categoryField = "country"; chart.startDuration = 1; // AXES // category var categoryAxis = chart.categoryAxis; categoryAxis.labelRotation = 90; categoryAxis.gridPosition = "start"; // value // in case you don't want to change default settings of value axis, // you don't need to create it, as one value axis is created automatically. // GRAPH var graph = new AmCharts.AmGraph(); graph.valueField = "visits"; graph.balloonText = "[[category]]: <b>[[value]]</b>"; graph.type = "column"; graph.lineAlpha = 0; graph.fillAlphas = 0.8; // display label text on each column graph.labelText = "[[value]]"; chart.addGraph(graph); // CURSOR var chartCursor = new AmCharts.ChartCursor(); chartCursor.cursorAlpha = 0; chartCursor.zoomable = false; chartCursor.categoryBalloonEnabled = false; chart.addChartCursor(chartCursor); chart.creditsPosition = "top-right"; chart.write("chartdiv"); }); </script> </head> <body> <div></div> </body> </html>
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