如何使用 itext 在 pdf 的页脚上添加页码,它应该照顾它的宽度?

How to add page number on the footer of pdf using itext which should take care of its width?

我的代码示例如下


    @Override
    public void onEndPage(PdfWriter writer, Document document) {
        addFooter(writer);
    }

    private void addFooter(PdfWriter writer){
        PdfPTable footer = new PdfPTable(2);
        try {
            // set defaults
            footer.setWidths(new int[]{2, 24});
            footer.setWidthPercentage(50);

            footer.setTotalWidth(527);
            footer.setLockedWidth(true);
            footer.getDefaultCell().setFixedHeight(30);
            footer.getDefaultCell().setBorder(Rectangle.TOP);
            footer.getDefaultCell().setBorderColor(BaseColor.RED);
            // here for the text Page 100 of, word of goes below in next line. 
            //It should be in same line.
            footer.addCell(new Phrase(String.format("Page %d of", Integer.parseInt(writer.getPageNumber()+"33")), new Font(Font.FontFamily.HELVETICA, 8)));

            // add placeholder for total page count
            PdfPCell totalPageCount = new PdfPCell(total);
            totalPageCount.setBorder(Rectangle.TOP);
            totalPageCount.setBorderColor(BaseColor.GREEN);
            footer.getDefaultCell().setHorizontalAlignment(Element.ALIGN_LEFT);
            footer.addCell(totalPageCount);

            // write page
            PdfContentByte canvas = writer.getDirectContent();
            canvas.beginMarkedContentSequence(PdfName.ARTIFACT);
            footer.writeSelectedRows(0, -1, 34, 20, canvas);
            canvas.endMarkedContentSequence();
        } catch(DocumentException de) {
            throw new ExceptionConverter(de);
        }
    }

}

此代码在个位数页码的情况下工作正常。但是当页面增加到两位数时,很少有文本会转移到下一行。例如,如果文本是第 10 页,共 10 页,那么单词 "of" 会出现在下一行。

您的页脚的第一列 table 非常小。实际上太小以至于较大的页码会自动导致换行。因此,通过替换

为第一列提供更多 space
footer.setWidths(new int[]{2, 24});

例如

footer.setWidths(new int[]{2, 20});

您在评论中回应了扩大第一列的提议

but it increases the unnecessary space even if change it to only one point more. It gives the output like Page 10 of 10. I mean after "Page 10 of", there is much more space.

要缩小间距,您可以右对齐第一列的内容,例如添加

footer.getDefaultCell().setHorizontalAlignment(Element.ALIGN_RIGHT);

在添加 "Page %d of" 单元格之前。

因此,

private void addFooterImproved(PdfWriter writer) {
    PdfPTable footer = new PdfPTable(2);
    try {
        // set defaults
        footer.setWidths(new int[]{2, 20});
        footer.setWidthPercentage(50);

        footer.setTotalWidth(527);
        footer.setLockedWidth(true);
        footer.getDefaultCell().setFixedHeight(30);
        footer.getDefaultCell().setBorder(Rectangle.TOP);
        footer.getDefaultCell().setBorderColor(BaseColor.RED);
        footer.getDefaultCell().setHorizontalAlignment(Element.ALIGN_RIGHT);
        footer.addCell(new Phrase(String.format("Page %d of", writer.getPageNumber()), new Font(Font.FontFamily.HELVETICA, 8)));

        // add placeholder for total page count
        PdfPCell totalPageCount = new PdfPCell(total);
        totalPageCount.setBorder(Rectangle.TOP);
        totalPageCount.setBorderColor(BaseColor.GREEN);
        footer.getDefaultCell().setHorizontalAlignment(Element.ALIGN_LEFT);
        footer.addCell(totalPageCount);

        // write page
        PdfContentByte canvas = writer.getDirectContent();
        canvas.beginMarkedContentSequence(PdfName.ARTIFACT);
        footer.writeSelectedRows(0, -1, 34, 20, canvas);
        canvas.endMarkedContentSequence();
    } catch(DocumentException de) {
        throw new ExceptionConverter(de);
    }
}

(CreateFooter辅助方法)

100 页文档的结果:

...