java - JFreeChart大数据无法读取轴

Question

我正在使用 JFreeChart 绘制折线图。该应用程序每 100 毫秒读取一次感官数据，因此在几分钟的捕获中会产生大量数据。我不动态绘制图表，它是静态的。我使用类别图，因为轴有时可以是十进制值，有时可以是字符串，有时可以是 boolean 值。我的问题是 X 轴(时间)有太多数据，我无法辨认文本:

有人知道我在这里能做什么吗？任何处理这个问题的提示或技巧都会很棒!

 private CategoryDataset createDataset() {
    String series1 = "First";
    String series2 = "Second";
    String category1 = "Category 1";
    String category2 = "Category 2";
    DefaultCategoryDataset dataset = new DefaultCategoryDataset();
    for (int i = 0; i < time.size(); i++) {
        dataset.addValue(Math.random(), series1, time.get(i));
    }
    return dataset;

}

private JFreeChart createChart(final CategoryDataset dataset) {

    // create the chart...
    final JFreeChart chart = ChartFactory.createLineChart(
            "Line Chart Demo 6", // chart title
            "Time", // x axis label
            "RPM", // y axis label
            dataset, // data
            PlotOrientation.VERTICAL,
            true, // include legend
            true, // tooltips
            false // urls
    );

    chart.setBackgroundPaint(Color.white);

    final CategoryPlot plot = chart.getCategoryPlot();
    plot.setBackgroundPaint(Color.white);
    plot.setDomainGridlinePaint(Color.white);
    plot.setRangeGridlinePaint(Color.white);

    final CategoryItemRenderer renderer = (CategoryItemRenderer) plot.getRenderer();

    plot.setRenderer(renderer);



    return chart;

}

public void setLists(ArrayList<String> time) {
    this.time = time;
    final CategoryDataset dataset = createDataset();
    final JFreeChart chart = createChart(dataset);
    final ChartPanel chartPanel = new ChartPanel(chart);
    chartPanel.setPreferredSize(new java.awt.Dimension(500, 270));
    setContentPane(chartPanel);
}

Answer 1

您可以通过添加以下内容来关闭标签和刻度线:

CategoryPlot plot = (CategoryPlot) chart.getPlot();
CategoryAxis cx = new CategoryAxis();
cx.setTickLabelsVisible(false);
cx.setTickMarksVisible(false);
plot.setDomainAxis(cx);

如果您想显示标签的子集(每个第 n 个值)，那么您需要对 CategoryAxis 进行子类化，以便可以覆盖 CategoryAxis#drawCategoryLabels() 和 CategoryAxis#drawTickMarks()