如何使用 iTextLibrary 在动态 pdf 中添加页眉和页脚? [英] How to add Header and Footer in dynamic pdf using iTextLibrary?

问题描述

我已经使用 iText 库创建了一个 PDF 文件动态，现在我想添加 Header 和 页脚，为此我添加了给定代码:

I have created a PDF file dynamically using iText Library, Now I want to add Header and Footer in PDF's pages, for this one I have added given code:

document.addHeader("My Header Title", "My Header Details");

但在我的 PDF 页面中，无法设置此标题.什么是我不知道的问题，如果您对此有任何想法，请分享您的想法.

But in my PDF's pages this header couldn't set. What is issue that I don't know, If you have any idea related to it,please share your thoughts.

推荐答案

如果您使用当前的 iText 版本(即目前为 5.4.x)，请查看示例 MovieHistory2 来自 iText in Action— 第 2 版 展示了如何在创建 PDF 时向 PDF 添加页眉(奇数页和偶数页的不同页眉).

In case you use a current iText version (i.e. 5.4.x as of now) have a look at the sample MovieHistory2 from iText in Action — 2nd Edition which shows how to add headers (different ones for odd and even pages) to a PDF while creating it.

最重要的是 PdfPageEventHelper 实现

/** Inner class to add a header and a footer. */
class HeaderFooter extends PdfPageEventHelper {
    /** Alternating phrase for the header. */
    Phrase[] header = new Phrase[2];
    /** Current page number (will be reset for every chapter). */
    int pagenumber;

    /**
     * Initialize one of the headers.
     * @see com.itextpdf.text.pdf.PdfPageEventHelper#onOpenDocument(
     *      com.itextpdf.text.pdf.PdfWriter, com.itextpdf.text.Document)
     */
    public void onOpenDocument(PdfWriter writer, Document document) {
        header[0] = new Phrase("Movie history");
    }

    /**
     * Initialize one of the headers, based on the chapter title;
     * reset the page number.
     * @see com.itextpdf.text.pdf.PdfPageEventHelper#onChapter(
     *      com.itextpdf.text.pdf.PdfWriter, com.itextpdf.text.Document, float,
     *      com.itextpdf.text.Paragraph)
     */
    public void onChapter(PdfWriter writer, Document document,
            float paragraphPosition, Paragraph title) {
        header[1] = new Phrase(title.getContent());
        pagenumber = 1;
    }

    /**
     * Increase the page number.
     * @see com.itextpdf.text.pdf.PdfPageEventHelper#onStartPage(
     *      com.itextpdf.text.pdf.PdfWriter, com.itextpdf.text.Document)
     */
    public void onStartPage(PdfWriter writer, Document document) {
        pagenumber++;
    }

    /**
     * Adds the header and the footer.
     * @see com.itextpdf.text.pdf.PdfPageEventHelper#onEndPage(
     *      com.itextpdf.text.pdf.PdfWriter, com.itextpdf.text.Document)
     */
    public void onEndPage(PdfWriter writer, Document document) {
        Rectangle rect = writer.getBoxSize("art");
        switch(writer.getPageNumber() % 2) {
        case 0:
            ColumnText.showTextAligned(writer.getDirectContent(),
                    Element.ALIGN_RIGHT, header[0],
                    rect.getRight(), rect.getTop(), 0);
            break;
        case 1:
            ColumnText.showTextAligned(writer.getDirectContent(),
                    Element.ALIGN_LEFT, header[1],
                    rect.getLeft(), rect.getTop(), 0);
            break;
        }
        ColumnText.showTextAligned(writer.getDirectContent(),
                Element.ALIGN_CENTER, new Phrase(String.format("page %d", pagenumber)),
                (rect.getLeft() + rect.getRight()) / 2, rect.getBottom() - 18, 0);
    }
}

是这样注册的:

    PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream(RESULT));
    HeaderFooter event = new HeaderFooter();
    writer.setBoxSize("art", new Rectangle(36, 54, 559, 788));
    writer.setPageEvent(event);

根据评论中的要求，onEndPage 方法的一个更简单的变体，带有静态标头而不是交替标头:

As requested in the comments, a simpler variant of the onEndPage method with a static header instead of the alternating one:

    public void onEndPage(PdfWriter writer, Document document)
    {
        Rectangle rect = writer.getBoxSize("art");
        ColumnText.showTextAligned(writer.getDirectContent(),
                Element.ALIGN_RIGHT, new Phrase("My static header text"),
                rect.getRight(), rect.getTop(), 0);
        ColumnText.showTextAligned(writer.getDirectContent(),
                Element.ALIGN_CENTER, new Phrase(String.format("page %d", pagenumber)),
                (rect.getLeft() + rect.getRight()) / 2, rect.getBottom() - 18, 0);
    }

这篇关于如何使用 iTextLibrary 在动态 pdf 中添加页眉和页脚?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！