How to convert image file to a pdf file in Android

问题

I am trying to convert image file (jpeg) in to pdf file in my Adroid application. I have used itextpdf jar and droidtext jar. Neither work for me. Below is the code while using itextpdf.

Document document = new Document();

String directoryPath = Environment.getExternalStorageDirectory().toString();

File newPdfFile = new File(directoryPath, "textview8.pdf");

FileOutputStream fileOutputStream = null;

try {
    fileOutputStream = new FileOutputStream(newPdfFile);
} catch (FileNotFoundException fnfe) {
    Log.w(TAG, "# Exception caz of fileOutputStream : " + fnfe);
}

BufferedOutputStream bufferedOutputStream = new BufferedOutputStream(fileOutputStream);

try {
    PdfWriter.getInstance(document, bufferedOutputStream);
} catch (DocumentException de) {
    Log.w(TAG, "# Exception caz of PdfWriter.getInstance : " + de);
}

document.open(); 

Image image = null;

try {
    image = Image.getInstance(directoryPath + File.separator + "textview1.JPEG");
} catch (BadElementException bee) {
    Log.w(TAG, "# First exception caz of image : " + bee);
} catch (MalformedURLException mue) {
    Log.w(TAG, "# Second exception caz of image : " + mue);
} catch (IOException ioe) {
    Log.w(TAG, "# Third exception caz of image : " + ioe);
}

try {
    document.add(image);
} catch (DocumentException de) {
    Log.w(TAG, "# Exception caz of document.add : " + de);
}

try {
    bufferedOutputStream.flush();
    bufferedOutputStream.close();

    fileOutputStream.flush();
    fileOutputStream.close();

} catch (IOException ioe) {
    Log.w(TAG, "# Exception caz of bufferedOutputStream.flush : " + ioe);
}

document.close();

This gives me an error with a NullPointerException because of the code line document.close();

When I comment that line and run the program, it gives me the following error.

Could not find class 'com.itextpdf.awt.PdfPrinterGraphics2D', referenced from method com.itextpdf.text.pdf.PdfContentByte.createPrinterGraphicsShapes

But the class they are telling can't find is already in the jar file, which means com.itextpdf.awt.PdfPrinterGraphics2D is existing in the project.

I have added the itextpdf-5.1.3.jar to the build path also. I tried this with a emulator as well as with a real device.

Can't figure out what I have done wrong. Please help...

回答1:

Just simply do this way it works fine

Document document=new Document();
String dirpath=android.os.Environment.getExternalStorageDirectory().toString();
PdfWriter.getInstance(document,new FileOutputStream(dirpath+"/imagedemo.pdf"));
document.open();
Image im=Image.getInstance(dirpath+"/"+"logo.png");  // Replace logo.png with your image name with extension 
document.add(im);
document.close();

回答2:

All the examples I've seen directly use the FileOutputStream, did you try without buffer?

PdfWriter.getInstance(document, fileOutputStream);

回答3:

Found a way to tackle with this problem. I have to do two changes in my code.

Implement DocListener interface in my Activity
Close streams after closing the document

Here are the changes of the second point

try {
    bufferedOutputStream.flush();

    fileOutputStream.flush();

    } catch (IOException ioe) {
        Log.w(TAG, "# Exception caz of flush : " + ioe);
    }

    document.close();

try {
    bufferedOutputStream.close();

    fileOutputStream.close();

    } catch (IOException ioe) {
        Log.w(TAG, "# Exception caz of close : " + ioe);
}

Still I cannot think the relationship with the Error given in the log and the working code :-/

来源：https://stackoverflow.com/questions/12315037/how-to-convert-image-file-to-a-pdf-file-in-android

标签

android

image

pdf

itextpdf