面积图接受一系列数据点(x,y)作为输入值,使用一条线连接它们,并映射所获得的线和轴之间的区域。在JavaFX中,您可以通过实例化javafx.scene.chart.AreaChart类来创建面积图。
在实例化此类时,必须传递Axis类的两个对象,它们代表x轴和y轴(作为构造函数的参数)。由于Axis类是抽象的,因此您需要传递其具体子类的对象NumberNumber(用于数字值)或CategoryAxis(字符串值)。
该XYChart.Data 类表示图表中的数据点,你可以通过实例这个类来创建一个数据点。
XYChart.Data dataPoint1 = new XYChart.Data(x-value, y-value)
XYChart.Data dataPoint2 = new XYChart.Data(x-value, y-value)
XYChart.Data dataPoint3 = new XYChart.Data(x-value, y-value)
一旦创建了所有必需的数据点,就可以创建实例化XYChart.Series类并将其添加数据所需的序列。
XYChart.Series series = XYChart.Series
series.getData().add(dataPoint1);
series.getData().add(dataPoint2);
series.getData().add(dataPoint3);
您可以根据需要创建任意数量的此类序列。
以下JavaFX示例演示了多个面积图的创建。
import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.stage.Stage;
import javafx.scene.chart.AreaChart;
import javafx.scene.chart.CategoryAxis;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart;
import javafx.scene.layout.StackPane;
public class AreaCharts_Multiple extends Application {
public void start(Stage stage) {
//定义x和y轴
CategoryAxis xAxis = new CategoryAxis();
NumberAxis yAxis = new NumberAxis();
//设置轴的标签
xAxis.setLabel("Month");
yAxis.setLabel("Temperature(°C)");
//创建面积图
AreaChart<String, Number> areaChart = new AreaChart<String, Number>(xAxis, yAxis);
//准备系列的数据点1-
XYChart.Series series1 = new XYChart.Series();
series1.getData().add(new XYChart.Data("Jan", 7.0));
series1.getData().add(new XYChart.Data("Feb", 6.9));
series1.getData().add(new XYChart.Data("March", 9.5));
series1.getData().add(new XYChart.Data("April", 14.5));
series1.getData().add(new XYChart.Data("May", 18.2));
series1.getData().add(new XYChart.Data("June", 21.5));
series1.getData().add(new XYChart.Data("July", 25.2));
series1.getData().add(new XYChart.Data("August", 26.5));
series1.getData().add(new XYChart.Data("Sep", 23.3));
series1.getData().add(new XYChart.Data("Oct", 18.3));
series1.getData().add(new XYChart.Data("Nov", 13.9));
series1.getData().add(new XYChart.Data("Dec", 9.6));
//准备系列2的数据点
XYChart.Series series2 = new XYChart.Series();
series2.getData().add(new XYChart.Data("Jan", -0.2));
series2.getData().add(new XYChart.Data("Feb", 0.8));
series2.getData().add(new XYChart.Data("March", 5.7));
series2.getData().add(new XYChart.Data("April", 11.3));
series2.getData().add(new XYChart.Data("May", 17.0));
series2.getData().add(new XYChart.Data("June", 22.0));
series2.getData().add(new XYChart.Data("July", 24.8));
series2.getData().add(new XYChart.Data("August", 24.1));
series2.getData().add(new XYChart.Data("Sep", 20.1));
series2.getData().add(new XYChart.Data("Oct", 14.1));
series2.getData().add(new XYChart.Data("Nov", 8.6));
series2.getData().add(new XYChart.Data("Dec", 2.5));
//准备系列的数据点3-
XYChart.Series series3 = new XYChart.Series();
series3.getData().add(new XYChart.Data("Jan", 3.9));
series3.getData().add(new XYChart.Data("Feb", 4.2));
series3.getData().add(new XYChart.Data("March", 5.7));
series3.getData().add(new XYChart.Data("April", 8.5));
series3.getData().add(new XYChart.Data("May", 11.9));
series3.getData().add(new XYChart.Data("June", 15.2));
series3.getData().add(new XYChart.Data("July", 17.0));
series3.getData().add(new XYChart.Data("August", 16.6));
series3.getData().add(new XYChart.Data("Sep", 14.2));
series3.getData().add(new XYChart.Data("Oct", 10.3));
series3.getData().add(new XYChart.Data("Nov", 6.6));
series3.getData().add(new XYChart.Data("Dec", 4.8));
//设置所有系列的名称
series1.setName("Tokyo");
series2.setName("New York");
series3.setName("London");
//将数据设置为面积图
areaChart.getData().addAll(series1, series2, series3);
//创建一个堆栈窗格来保存图表
StackPane pane = new StackPane(areaChart);
pane.setPadding(new Insets(15, 15, 15, 15));
pane.setStyle("-fx-background-color: BEIGE");
//设置场景
Scene scene = new Scene(pane, 595, 350);
stage.setTitle("Area Chart");
stage.setScene(scene);
stage.show();
}
public static void main(String args[]){
launch(args);
}
}
输出结果