java - POI 4.1.0 折线图 y 系列显示错误的图例

Question

如何在 y 系列上创建带有单个图例的折线图，而不是在 x 系列上显示多个图例

int rows = numberOfRows - 1;
int cols = headers.size();

XSSFDrawing drawing = sheet.createDrawingPatriarch();
XSSFClientAnchor anchor = drawing.createAnchor(0, 0, 0, 0, 0, 5, 10, 15);
XSSFChart chart = drawing.createChart(anchor);
chart.displayBlanksAs(DisplayBlanks.GAP);

XDDFChartLegend legend = chart.getOrAddLegend();
legend.setPosition(LegendPosition.TOP_RIGHT);

// Use a category axis for the bottom axis.
XDDFCategoryAxis bottomAxis = chart.createCategoryAxis(AxisPosition.BOTTOM);
bottomAxis.setOrientation(AxisOrientation.MAX_MIN);
bottomAxis.setTitle("Date");

XDDFValueAxis rightAxis = chart.createValueAxis(AxisPosition.RIGHT);
rightAxis.setTitle("Rates");
rightAxis.setCrosses(AxisCrosses.AUTO_ZERO);

XDDFChartLegend chartLegend = chart.getOrAddLegend();
chartLegend.setPosition(LegendPosition.TOP_RIGHT);
chartLegend.setOverlay(false);

XDDFLineChartData lineChartData = (XDDFLineChartData) chart.createData(ChartTypes.LINE, bottomAxis, rightAxis);

XDDFDataSource<String> xs = XDDFDataSourcesFactory.fromStringCellRange(sheet, new CellRangeAddress(1, rows, 0, 0));

for (int col = 1; col < cols; col++) {
    XDDFNumericalDataSource<Double> ys1 = XDDFDataSourcesFactory.fromNumericCellRange(sheet, new CellRangeAddress(1, rows, col, col));
    XDDFLineChartData.Series series1 = (XDDFLineChartData.Series) lineChartData.addSeries(xs, ys1);
    series1.setTitle(headers.get(col), null);
    series1.setSmooth(false);
    series1.setMarkerStyle(MarkerStyle.NONE);
}

chart.plot(lineChartData);

上图显示了我当前的绘图折线图，y 系列预计只有 1 个图例，但显示了多个

上图折线图是使用Excel绘制的，y系列仅显示1个图例

Answer 1

有一个设置可以改变图表中同系列数据标记的颜色。请参阅:Vary the colors of same-series data markers in a chart 。在 Excel 2007 之前，默认情况下该值为 false。现在，Microsoft决定将该设置设置为默认true。因此，如果您不想要它，则需要明确设置 false。

就您而言:

...
XDDFLineChartData lineChartData = (XDDFLineChartData) chart.createData(ChartTypes.LINE, bottomAxis, rightAxis);
lineChartData.setVaryColors(false);
...