如何向PDF文档中插入图片？

有两种方法可以帮助您将图片插入到PDF文档中。第一钟是调用PDFPage.addImageFromFilePath接口。您可以参考如下示例代码，该代码将图片插入到PDF文档的首页：

备注：在调用PDFPage.addImageFromFilePath接口之前，您需要获取并解析将要添加图片的页面。

String path = "mnt/sdcard/input_files/sample.pdf";
try {

    // Initialize a PDFDoc object with the path to the PDF file.
    PDFDoc document = new PDFDoc(path);

    // Load the unencrypted document content.
    document.load(null);

    // Get the first page of the PDF file.
    PDFPage page = document.getPage(0);

    // Parse the page.
    if (!page.isParsed()) {
        Progressive parse = page.startParse(e_ParsePageNormal, null, false);
        int state = Progressive.e_ToBeContinued;
        while (state == Progressive.e_ToBeContinued) {
            state = parse.resume();
        }
    }

    // Add an image to the first page.
    page.addImageFromFilePath("mnt/sdcard/input_files/2.png", new PointF(20, 30), 60, 50, true);

    // Save the document that has added the image.
    document.saveAs("mnt/sdcard/input_files/sample_image.pdf", PDFDoc.e_SaveFlagNormal);

} catch (Exception e) {
    e.printStackTrace();
}

第二种是使用PDFPage.addAnnot接口在指定的页面添加一个stamp，然后将图片转换为位图，并将位图设置给刚添加的stamp注释。您可以参考以下的示例代码，该代码将图片作为stamp注释插入到PDF文件的首页：

String path = "mnt/sdcard/input_files/sample.pdf";
try {

    // Initialize a PDFDoc object with the path to the PDF file.
    PDFDoc document = new PDFDoc(path);

    // Load the unencrypted document content.
    document.load(null);

    // Get the first page of the PDF file.
    PDFPage page = document.getPage(0);

    // Add a stamp annotation to the first page.
    Stamp stamp = new Stamp(page.addAnnot(Annot.e_Stamp, new RectF(100, 350, 250, 150))); 

    // Load a local image and convert it to a Bitmap.
    Bitmap bitmap = BitmapFactory.decodeFile("mnt/sdcard/input_files/2.png");

    // Set the bitmap to the added stamp annotation.
    stamp.setBitmap(bitmap);

    //Reset appearance stream.
    stamp.resetAppearanceStream();

    // Save the document that has added the stamp annotation.
    document.saveAs("mnt/sdcard/input_files/sample_image.pdf", PDFDoc.e_SaveFlagNormal);

} catch (Exception e) {
    e.printStackTrace();
}