对于Apache poi折线图，如何使第一列不在y轴上显示？

问题描述

here is the "Asis position in excel"

now the line chart looks like

what I want

谢谢大家！！

这是Apache网站上的代码示例：

public class LineChart {

    public static void main(String[] args) throws IOException {
        try (XSSFWorkbook wb = new XSSFWorkbook()) {
            XSSFSheet sheet = wb.createSheet("linechart");
            final int NUM_OF_ROWS = 3;
            final int NUM_OF_COLUMNS = 10;

            // Create a row and put some cells in it. Rows are 0 based.
            Row row;
            Cell cell;
            for (int rowIndex = 0; rowIndex  xs = XDDFDataSourcesFactory.fromNumericCellRange(sheet, new CellRangeAddress(0, 0, 0, NUM_OF_COLUMNS - 1));
            XDDFNumericalDataSource ys1 = XDDFDataSourcesFactory.fromNumericCellRange(sheet, new CellRangeAddress(1, 1, 0, NUM_OF_COLUMNS - 1));
            XDDFNumericalDataSource ys2 = XDDFDataSourcesFactory.fromNumericCellRange(sheet, new CellRangeAddress(2, 2, 0, NUM_OF_COLUMNS - 1));

            XDDFLineChartData data = (XDDFLineChartData) chart.createData(ChartTypes.LINE, bottomAxis, leftAxis);
            XDDFLineChartData.Series series1 = (XDDFLineChartData.Series) data.addSeries(xs, ys1);
            series1.setTitle("a", null); // https://stackoverflow.com/questions/21855842
            //series1.setSmooth(false); // https://stackoverflow.com/questions/29014848
            series1.setMarkerStyle(MarkerStyle.NONE); // https://stackoverflow.com/questions/39636138
            XDDFLineChartData.Series series2 = (XDDFLineChartData.Series) data.addSeries(xs, ys2);
            series2.setTitle("b", null);
            //series2.setSmooth(true);
            //series2.setMarkerSize((short) 6);
            series2.setMarkerStyle(MarkerStyle.NONE); // https://stackoverflow.com/questions/39636138

            CTBoolean ctBoolean = CTBoolean.Factory.newInstance();
            ctBoolean.setVal(false);
            CTPlotArea plotArea = chart.getCTChart().getPlotArea();
            chart.getCTChartSpace().setRoundedCorners(ctBoolean);
            for (CTLineSer ser : plotArea.getLineChartArray()[0].getSerArray()) {
                CTDLbls ctdLbls = ser.addNewDLbls();

                ctdLbls.setShowSerName(ctBoolean);
                ctdLbls.setShowLegendKey(ctBoolean);
                ctdLbls.setShowLeaderLines(ctBoolean);
                ctdLbls.setShowCatName(ctBoolean);
                CTDLblPos ctdLblPos = CTDLblPos.Factory.newInstance();
                ctdLblPos.setVal(STDLblPos.CTR);
                CTDLblPos.Factory.newInstance();
                ctdLbls.setDLblPos(ctdLblPos);
            }

            chart.plot(data);

            // if your series have missing values like https://stackoverflow.com/questions/29014848
            // chart.displayBlanksAs(DisplayBlanks.GAP);

            // https://stackoverflow.com/questions/24676460
            solidLineSeries(data, 0, PresetColor.LIGHT_GREEN);
            solidLineSeries(data, 1, PresetColor.DARK_RED);

            // Write the output to a file
            try (FileOutputStream fileOut = new FileOutputStream("ooxml-line-chart.xlsx")) {
                wb.write(fileOut);
            }
        }
    }
    //CTPresetLineDashProperties
    private static void solidLineSeries(XDDFChartData data, int index, PresetColor color) {
        XDDFSolidFillProperties fill = new XDDFSolidFillProperties(XDDFColor.from(color));
        XDDFLineProperties line = new XDDFLineProperties();
        if (index == 0) {
            line.setPresetDash(new XDDFPresetLineDash(PresetLineDash.DOT));
        }
        line.setFillProperties(fill);
        XDDFChartData.Series series = data.getSeries().get(index);
        XDDFShapeProperties properties = series.getShapeProperties();
        if (properties == null) {
            properties = new XDDFShapeProperties();
        }
        properties.setLineProperties(line);
        series.setShapeProperties(properties);
    }
}

思路：

默认情况下，值轴和类别轴在类别点上完全相交。因此，如果值轴在0点处与类别轴交叉，则现在看起来像您的结果。

但是如果x轴是类别轴，则存在设置XDDFValueAxis.setCrossBetween。如果将其设置为AxisCrossBetween.BETWEEN，则值轴与类别点之间的类别轴交叉。这看起来像您想要的。

所以在您的情况下：

...
            // Use a category axis for the bottom axis.
            XDDFCategoryAxis bottomAxis = chart.createCategoryAxis(AxisPosition.BOTTOM);
            //bottomAxis.setTitle("x"); // https://stackoverflow.com/questions/32010765
            XDDFValueAxis leftAxis = chart.createValueAxis(AxisPosition.LEFT);
            //leftAxis.setTitle("f(x)");
            leftAxis.setCrosses(AxisCrosses.AUTO_ZERO);

            leftAxis.setCrossBetween(AxisCrossBetween.BETWEEN);
...

顺便说一句：您应该摆脱不推荐使用的方法。

例如，不推荐使用get...Array()的ooxml-schemas方法。您可以使用get...Array(item)从数组中获取具体项目，或者使用List获得get...List()。

根据您的情况：

...
            //for (CTLineSer ser : plotArea.getLineChartArray()[0].getSerArray()) {
            for (CTLineSer ser : plotArea.getLineChartArray(0).getSerList()) {
...

而且XDDFChartData.getSeries()也已弃用。如果需要一个系列，请使用XDDFChartData.getSeries(index)

根据您的情况：

...
        //XDDFChartData.Series series = data.getSeries().get(index);
        XDDFChartData.Series series = data.getSeries(index);
...

以上内容就是爱站技术频道小编为大家分享的对于Apache poi折线图，如何使第一列不在y轴上显示？看完以上分享之后，大家应该都知道怎么去显示了吧。