1
我试图运行下面的代码抛出异常,它抛出的异常getSeriesVisible:的JFreeChart上getSeriesVisible
chart.addChangeListener(new ChartChangeListener() {
int indexChanged = -1;
@Override
public void chartChanged(ChartChangeEvent event) {
XYPlot ff = chart.getXYPlot();
XYItemRenderer y = ff.getRenderer();
boolean b = y.getSeriesVisible(0);
// chart.getXYPlot().getRenderer().setSeriesVisible(0, b);
}
});
消息:异常在线程 “AWT-EventQueue的-0” 显示java.lang.NullPointerException
任何想法?
更新:我加入了几个系列,并生成图表如下:
XYSeriesCollection data = new XYSeriesCollection();
XYSeries series = new XYSeries("Series 1", true);
series.add(1, 2);
series.add(3, 5);
series.add(8, 10);
series.add(11, 3);
series.add(8, 10);
data.addSeries(series);
series = new XYSeries("Series 2");
series.add(5, -2);
series.add(7, 6);
series.add(8, 12);
series.add(11, -2);
series.add(15, 10);
data.addSeries(series);
final JFreeChart chart = ChartFactory.createXYLineChart("Chart", "X", "Y", data, PlotOrientation.VERTICAL, true, true, false);
谢谢,它被认为是isSeriesVisible – Bober02 2012-08-07 06:18:36