瓦丁图表工具提示动态格式化程序

Question

Vaadin 图表是否提供了一种动态格式化工具提示的方法。 我想将一些逻辑绑定到工具提示上的值表示。 代替SOME_STRING，我需要反向规范化函数来更改值。

Map coefficients = new HashMap();
Chart chart = new Chart(ChartType.LINE);
Configuration conf = chart.getConfiguration();
Tooltip tooltip = conf.getTooltip();
tooltip.setFormatter(
"function() { " +
"return SOME_STRING }"
);
func reverseNormalization(String name, Double normalizedValue) {
return normalizedValue * coefficients.get(name);;
}

Answer 1

下面是一个示例：

conf.getTooltip().setPointFormatter(
"function() { " +
"var category = this.x; " +
"var multiplier = 10; " +
"switch (category) " + 
"{ " + 
"   case 0: " + 
"       multiplier = 10; " + 
"       break; " + 
"   case 1: " + 
"       multiplier = 20; " + 
"       break; " + 
"   case 2: " + 
"       multiplier = 30; " + 
"       break; " + 
"   default:  " + 
"       multiplier = 50; " + 
"}" +
"var tipTxt = this.series.name + ': <b>' + this.y*multiplier + '</b><br>'; " +
"return tipTxt; " +
"}"  
);

this.x将为您提供工具提示显示的点的类别值(从零开始(。您可以使用 this.x、this.y 和 this.series.name 来应用动态计算和格式。