POI设置单元格背景为自定义色彩(POI setting Cell Background to a

我想自定义颜色设置为一个单元格背景。
我用HSSFWorkbook （不能用别的）。

HSSFPalette palette = aWorkBook.getCustomPalette();             
Color col = new Color(backgroundColor);                     
HSSFColor myColor  = palette.addColor((byte) 10, (byte) 11, (byte) 12);

我得到这个错误： java.lang.RuntimeException: Could not find free color index

Answer 1:

因为调色板充满你得到这个错误。什么，你需要做的是覆盖预设的颜色。下面是我使用的函数的例子：

public HSSFColor setColor(HSSFWorkbook workbook, byte r,byte g, byte b){
    HSSFPalette palette = workbook.getCustomPalette();
    HSSFColor hssfColor = null;
    try {
        hssfColor= palette.findColor(r, g, b); 
        if (hssfColor == null ){
            palette.setColorAtIndex(HSSFColor.LAVENDER.index, r, g,b);
            hssfColor = palette.getColor(HSSFColor.LAVENDER.index);
        }
    } catch (Exception e) {
        logger.error(e);
    }

    return hssfColor;
}

后来又用它作为背景色：

HSSFColor lightGray =  setColor(workbook,(byte) 0xE0, (byte)0xE0,(byte) 0xE0);
style2.setFillForegroundColor(lightGray.getIndex());
style2.setFillPattern(CellStyle.SOLID_FOREGROUND);

Answer 2:

见http://poi.apache.org/spreadsheet/quick-guide.html#CustomColors 。

自定义颜色

HSSF：

HSSFWorkbook wb = new HSSFWorkbook();
HSSFSheet sheet = wb.createSheet();
HSSFRow row = sheet.createRow((short) 0);
HSSFCell cell = row.createCell((short) 0);
cell.setCellValue("Default Palette");

//apply some colors from the standard palette,
// as in the previous examples.
//we'll use red text on a lime background

HSSFCellStyle style = wb.createCellStyle();
style.setFillForegroundColor(HSSFColor.LIME.index);
style.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);

HSSFFont font = wb.createFont();
font.setColor(HSSFColor.RED.index);
style.setFont(font);

cell.setCellStyle(style);

//save with the default palette
FileOutputStream out = new FileOutputStream("default_palette.xls");
wb.write(out);
out.close();

//now, let's replace RED and LIME in the palette
// with a more attractive combination
// (lovingly borrowed from freebsd.org)

cell.setCellValue("Modified Palette");

//creating a custom palette for the workbook
HSSFPalette palette = wb.getCustomPalette();

//replacing the standard red with freebsd.org red
palette.setColorAtIndex(HSSFColor.RED.index,
        (byte) 153,  //RGB red (0-255)
        (byte) 0,    //RGB green
        (byte) 0     //RGB blue
);
//replacing lime with freebsd.org gold
palette.setColorAtIndex(HSSFColor.LIME.index, (byte) 255, (byte) 204, (byte) 102);

//save with the modified palette
// note that wherever we have previously used RED or LIME, the
// new colors magically appear
out = new FileOutputStream("modified_palette.xls");
wb.write(out);
out.close();

XSSF：

XSSFWorkbook wb = new XSSFWorkbook();
XSSFSheet sheet = wb.createSheet();
XSSFRow row = sheet.createRow(0);
XSSFCell cell = row.createCell( 0);
cell.setCellValue("custom XSSF colors");

XSSFCellStyle style1 = wb.createCellStyle();
style1.setFillForegroundColor(new XSSFColor(new java.awt.Color(128, 0, 128)));
style1.setFillPattern(CellStyle.SOLID_FOREGROUND);

Answer 3:

不要忘记调用此。

style.setFillPattern(CellStyle.Align_Fill);

参数可根据您的需要是不同的。也许CellStyle.FINE_DOTS左右。

Answer 4:

插槽免费从NPOI Excel中indexedcolors 57+

            Color selColor;

        var wb = new HSSFWorkbook();

        var sheet = wb.CreateSheet("NPOI");
        var style = wb.CreateCellStyle();
        var font = wb.CreateFont();
        var palette = wb.GetCustomPalette();

        short indexColor = 57; 
        palette.SetColorAtIndex(indexColor, (byte)selColor.R, (byte)selColor.G, (byte)selColor.B);

        font.Color = palette.GetColor(indexColor).Indexed;

Answer 5:

正如指出的弗拉德的答案，你跑出来的自由颜色的插槽。要解决这个问题的方法之一是缓存的颜色：每当你尝试RGB组合，常规应先检查，如果组合是在缓存中; 如果是在缓存中，那么它应该使用那一个，而不是从头开始创建一个新的; 新的颜色会那么如果他们没有在缓存中，才能创建。

下面是我使用的执行情况; 它采用XSSF加番石榴的LoadingCache并朝从CSS generationg XSSF颜色面向rgb(r, g, b)的声明，但它应该是比较琐碎，以使其适应HSSF：

    private final LoadingCache<String, XSSFColor> colorsFromCSS = CacheBuilder.newBuilder()
            .build(new CacheLoader<String, XSSFColor>() {

                private final Pattern RGB = Pattern.compile("rgb\\(\\s*(\\d+)\\s*, \\s*(\\d+)\\s*,\\s*(\\d+)\\s*\\)");

                @Override
                public XSSFColor load(String style) throws Exception {
                    Matcher mat = RGB.matcher(style);
                    if (!mat.find()) {
                        throw new IllegalStateException("Couldn't read CSS color: " + style);
                    }                       
                    return new XSSFColor(new java.awt.Color(
                            Integer.parseInt(mat.group(1)), 
                            Integer.parseInt(mat.group(2)), 
                            Integer.parseInt(mat.group(3))));
                }

            });

也许别人可以发表HSSF相同呢？ ;）

文章来源: POI setting Cell Background to a Custom Color