jfreechart 使用-优快云博客

本文介绍了如何使用JFreeChart库处理图表上的鼠标事件，包括获取鼠标位置对应的坐标值、响应点击事件及移动事件等。通过示例代码展示了如何实现这些功能，并提供了具体的实现思路。

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http://ltc603.iteye.com/blog/30207

http://langhua9527.iteye.com/blog/395244

http://chinaxxren.iteye.com/blog/701297

http://hoocy.iteye.com/blog/327066

http://www.iteye.com/wiki/topic/360994

public String getToolTipText(MouseEvent e) {
// TODO Auto-generated method stub
// return super.getToolTipText(e);

  Point2D p = translateScreenToJava2D(e.getPoint());
  ChartRenderingInfo info = getChartRenderingInfo();
  Rectangle2D dataArea = info.getPlotInfo().getDataArea();

  // check if the mouse is really in the data area
  if (dataArea.contains(p) == false) {
   return null;
  }

XYPlot plot = (XYPlot) chart.getPlot();

ValueAxis domainAxis = plot.getDomainAxis();
RectangleEdge domainAxisEdge = plot.getDomainAxisEdge();

double chartX = domainAxis.java2DToValue(p.getX(), dataArea,
domainAxisEdge);

  ValueAxis yAxis = plot.getRangeAxis();
  RectangleEdge yAxisEdge = plot.getRangeAxisEdge();

  double chartY = yAxis.java2DToValue(p.getY(), dataArea, yAxisEdge);

  String value = String.format("x = %.1f, y= %.1f", chartX, chartY);

//  return String.valueOf(chartX);

  return value;

}

Rectangle2D dataArea = chartPanel.getChartRenderingInfo().getPlotInfo().getDataArea();
Point2D p = chartPanel.translateScreenToJava2D(pt);
double chartX = xyplot.getDomainAxis().java2DToValue(p.getX(), dataArea, xyplot.getDomainAxisEdge());
double chartY = xyplot.getRangeAxis().java2DToValue(p.getY(), dataArea, xyplot.getRangeAxisEdge());

chartPanel
  .addChartMouseListener(new org.jfree.chart.ChartMouseListener() {
   public void chartMouseClicked(ChartMouseEvent evt) {
    try {
     if (evt.getChart() != null
       & evt.getEntity() != null) {
      CategoryItemEntity cie = (CategoryItemEntity) evt
        .getEntity();
      if (cie.getCategory() == null)
       return;
      if (cie.getCategoryIndex() >= 0) {
       cie = (CategoryItemEntity) evt.getEntity();
       int i = cie.getCategoryIndex();
       System.out.println("Your Selected Index > "
         + i);
      }
     } else
      return;
    } catch (Exception ce) {
     System.out.println("Error" + ce);
    }
   }

public void chartMouseMoved(ChartMouseEvent event) {

    int x = event.getTrigger().getX();
    int y = event.getTrigger().getY();
    ChartEntity entity = event.getEntity();
    if (entity != null) {
     System.out.println("Mouse moved: " + x + ", " + y
       + ": " + entity.toString());
    } else {
     System.out.println("Mouse moved: " + x + ", " + y
       + ": null entity.");
    }
   }
  });