Convert android layout to PDF file

You can use custom library such as https://github.com/HendrixString/Android-PdfMyXml but there is another way that explained here - How to convert Android View to PDF - that generate a pdf that contains bitmap of your layout

I made a library to achieve this objective.

The main code snippet is -

 PdfGenerator.getBuilder()
                        .setContext(context)
                        .fromLayoutXMLSource()
                        .fromLayoutXML(R.layout.layout_print,R.layout.layout_print)
            /* "fromLayoutXML()" takes array of layout resources.
             * You can also invoke "fromLayoutXMLList()" method here which takes list of layout resources instead of array. */
                        .setDefaultPageSize(PdfGenerator.PageSize.A4)
            /* It takes default page size like A4,A5. You can also set custom page size in pixel
             * by calling ".setCustomPageSize(int widthInPX, int heightInPX)" here. */
                        .setFileName("Test-PDF")
            /* It is file name */
                        .setFolderName("FolderA/FolderB/FolderC")
            /* It is folder name. If you set the folder name like this pattern (FolderA/FolderB/FolderC), then
             * FolderA creates first.Then FolderB inside FolderB and also FolderC inside the FolderB and finally
             * the pdf file named "Test-PDF.pdf" will be store inside the FolderB. */
                        .openPDFafterGeneration(true)
            /* It true then the generated pdf will be shown after generated. */
                        .build(new PdfGeneratorListener() {
                            @Override
                            public void onFailure(FailureResponse failureResponse) {
                                super.onFailure(failureResponse);
                /* If pdf is not generated by an error then you will findout the reason behind it
                 * from this FailureResponse. */
                            }

                            @Override
                            public void showLog(String log) {
                                super.showLog(log);
                /*It shows logs of events inside the pdf generation process*/ 
                            }

                            @Override
                            public void onSuccess(SuccessResponse response) {
                                super.onSuccess(response);
                /* If PDF is generated successfully then you will find SuccessResponse 
                 * which holds the PdfDocument,File and path (where generated pdf is stored)*/
                
                            }
                        });

I have tried many ways.
Finally got an answer Using this library https://mvnrepository.com/artifact/com.itextpdf/itextpdf/5.0.6
Layout to image and place it in pdf

import com.itextpdf.text.Document;
import com.itextpdf.text.Image;
import com.itextpdf.text.pdf.PdfWriter;

String dirpath;
public void layoutToImage(View view) {
    // get view group using reference  
    relativeLayout = (RelativeLayout) view.findViewById(R.id.print);
    // convert view group to bitmap
    relativeLayout.setDrawingCacheEnabled(true);
    relativeLayout.buildDrawingCache();
    Bitmap bm = relativeLayout.getDrawingCache();
    Intent share = new Intent(Intent.ACTION_SEND);
    share.setType("image/jpeg");
    ByteArrayOutputStream bytes = new ByteArrayOutputStream();
    bm.compress(Bitmap.CompressFormat.JPEG, 100, bytes);

    File f = new File(Environment.getExternalStorageDirectory() + File.separator + "image.jpg");
    try {
        f.createNewFile();
        FileOutputStream fo = new FileOutputStream(f);
        fo.write(bytes.toByteArray());
    } catch (IOException e) {
        e.printStackTrace();
    }

}
public void imageToPDF() throws FileNotFoundException {
    try {
        Document document = new Document();
        dirpath = android.os.Environment.getExternalStorageDirectory().toString();
        PdfWriter.getInstance(document, new FileOutputStream(dirpath + "/NewPDF.pdf")); //  Change pdf's name.
        document.open();
        Image img = Image.getInstance(Environment.getExternalStorageDirectory() + File.separator + "image.jpg");  
        float scaler = ((document.getPageSize().getWidth() - document.leftMargin()
                - document.rightMargin() - 0) / img.getWidth()) * 100; 
        img.scalePercent(scaler);
        img.setAlignment(Image.ALIGN_CENTER | Image.ALIGN_TOP);
        document.add(img);
        document.close();
        Toast.makeText(this, "PDF Generated successfully!..", Toast.LENGTH_SHORT).show();
    } catch (Exception e) {

    }
}

The above answer is correct, it throws an Exception error at the following line.

 bm.compress(Bitmap.CompressFormat.JPEG, 100, bytes);

Bcoz of this line of code return null

  Bitmap bm = relativeLayout.getDrawingCache();

So I have done some more research on Bitmap coming null.I use this method which first converts view to Image. Then you can use above function i.e imageToPDF() which works well.Below is my method.

 public void convertCertViewToImage()
 {

        scrollView.setDrawingCacheEnabled(true);
        scrollView.measure(View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED),
                View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
        scrollView.layout(0, 0, scrollView.getMeasuredWidth(), scrollView.getMeasuredHeight());
        scrollView.buildDrawingCache();
        Bitmap bm = Bitmap.createBitmap(scrollView.getDrawingCache());
        scrollView.setDrawingCacheEnabled(false); // clear drawing cache
        Intent share = new Intent(Intent.ACTION_SEND);
        share.setType("image/jpg");

        ByteArrayOutputStream bytes = new ByteArrayOutputStream();
        bm.compress(Bitmap.CompressFormat.JPEG, 100, bytes);

        File f = new File(getExternalFilesDir(null).getAbsolutePath() + File.separator + "Certificate" + File.separator + "myCertificate.jpg");

        f.createNewFile();
        FileOutputStream fo = new FileOutputStream(f);
        fo.write(bytes.toByteArray());

}