Java 如何在JFreeChart中将ChartPanel坐标转换为XYPlot坐标

我在ChartPanel上实现了所有Listner。在鼠标拖动事件中，我将注释上的坐标更改为重绘，以显示拖动操作。工作正常，但坐标有点混乱。实际上，我得到的坐标是在ChartPanel的上下文中，它随后将转换为XYPlots的轴值，因此注释是在奇怪的位置绘制的。

您需要使用

java2DToValue（）

将

MouseEvent

XY坐标转换为图表坐标

图表面板

鼠标操作代码

Rectangle2D dataArea = chartPanel.getChartRenderingInfo().getPlotInfo().getDataArea();
XYPlot xyPlot = chartPanel.getChart().getXYPlot();
// event is the MouseEvent from one of the MouseEvent functions
// store the location and use it later to place the annotation
java.awt.Point clickLocation = new Point(event.getX(), event.getY()); 

double x = xyPlot.getDomainAxis().java2DToValue(clickLocation.getX(), dataArea, xyPlot.getDomainAxisEdge());
double y = xyPlot.getRangeAxis().java2DToValue(clickLocation.getY(), dataArea, xyPlot.getRangeAxisEdge());
String text = Double.toString(x) + " " + Double.toString(y);

XYTextAnnotation annotation = new XYTextAnnotation(text, x, y);
plot.addAnnotation(annotation);

注释代码

Rectangle2D dataArea = chartPanel.getChartRenderingInfo().getPlotInfo().getDataArea();
XYPlot xyPlot = chartPanel.getChart().getXYPlot();
// event is the MouseEvent from one of the MouseEvent functions
// store the location and use it later to place the annotation
java.awt.Point clickLocation = new Point(event.getX(), event.getY()); 

double x = xyPlot.getDomainAxis().java2DToValue(clickLocation.getX(), dataArea, xyPlot.getDomainAxisEdge());
double y = xyPlot.getRangeAxis().java2DToValue(clickLocation.getY(), dataArea, xyPlot.getRangeAxisEdge());
String text = Double.toString(x) + " " + Double.toString(y);

XYTextAnnotation annotation = new XYTextAnnotation(text, x, y);
plot.addAnnotation(annotation);