How to convert Xamarin.Forms XAML UI page to PDF file? - xaml

In Xamarin.Forms, I want to convert my xaml page UI (sometimes my page is scrollable when having more content) into the PDF. I have tried the PDFSharp (https://github.com/akgulebubekir/PDFSharp.Xamarin.Forms) open source. But it works only on UWP and having some issues in iOS and Android.
So is there any free open source plugin available to convert XAML UI into PDF in all three platforms? If open source not available, is there any other way or work around to achieve it in android, ios & UWP?
Thanks in advance.

I had a bit of trouble with this and managed to do it using UIkit and PdfKit tools.
Here is an exemple:
using UIKit;
using PdfKit;
//Calculate scroll View height
double xamlHeight = XamlFullPage.Height;
int numberOfPages = (int)Math.Ceiling(xamlHeight / Application.Current.MainPage.Height);
// Create a new PDF document
PdfDocument document = new PdfDocument();
for (int i = 0; i<numberOfPages; i++) //while the all the page have not been taken into account
{
await SummaryScrollView.ScrollToAsync(0, i*Application.Current.MainPage.Height, false).ConfigureAwait(false); //find the beginnig of the current page
//Captures the XAML page as image and returns the image in memory stream
var image = UIScreen.MainScreen.Capture();
// Create a page with the printscreen
PdfPage page = new PdfPage(image);
//insert page in the i position
document.InsertPage(page, i);
page.Dispose();
}
//Write file in temp foleder
document.Write(Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "TuitionFees" + fileName + ".pdf"));`

Related

ImageMagick.Net - convert pdf to tiff

I am running into an issue when converting from pdf to tiff. Here is the code I used (based on a sample provided in the documentation):
private void convImageMx(string pdfFile)
{
var settings = new MagickReadSettings();
// Settings the density to 300 dpi will create an image with a better quality
settings.Density = new Density(300, 300);
settings.ColorType = ColorType.TrueColor;
string tifpath = Path.GetDirectoryName(pdfFile) + "\\" + Path.GetFileNameWithoutExtension(pdfFile);
using (var images = new MagickImageCollection())
{
// Add all the pages of the pdf file to the collection
images.Read(pdfFile, settings);
var page = 1;
foreach (var image in images)
{
// Write page to file that contains the page number
image.Format = MagickFormat.Ptif;
image.Crop(image.Width, image.Height);
image.Write(tifpath + "_p_" + page + ".tif");
page++;
}
}
}
When I provide a multiple pdf as input, I get multiple tiff files - one file per page. However, each file contains 7 pages which are shrinking images of the original page and the size is very large (original pdf size is 328k, the size of one tiff is 67mb!).
I think I need to set the compression property as well as crop property correctly. But did not find any documentation with .NET.
[EDIT] I commented the line with density so that the size issue is fixed. However, the repeating images is still an issue.

Generating and Downloading a PDF

I am developing an Android app for flight reservation and i am using firebase Database for storing and retriving data. I need to generate a PDF of Ticket and contents should be changed as per passenger details and stored in local directory. I have a template of Ticket. What should i do?
Thank you in advance.
Since Android 5 you can use PdfDocument and its friend classes to generate a PDF document on Android device. The official documentation is here. There is no library to use a template with PdfDocument. You have to use some drawing primitive to accomplish your task.
Here is a sample to generate a PDF with a single page A4:
// create a new document
PdfDocument document = new PdfDocument();
// crate a page description
PageInfo pageInfo = new PageInfo.Builder(595, 842, 1).create();
// start a page
Page page = document.startPage(pageInfo);
Canvas canvas=page.getCanvas());
// draw something on the page
Paint paint = new Paint();
paint.setColor(Color.RED);
canvas.drawCircle(50, 50, 30, paint);
// finish the page
document.finishPage(page);
// write the document content
document.writeTo(getOutputStream());
// close the document
document.close();
The page content is defined with Canvas object. Just another example. I hope this helps you.

iTextSharp rotated PDF page reverts orientation when file is rasterized at print house

Using iTextSharp I am creating a PDF composed of a collection of existing PDFs, some of the included PDFs are landscape orientation and need to be rotated. So, I do the following:
private static void AdjustRotationIfNeeded(PdfImportedPage pdfImportedPage, PdfReader reader, int documentPage)
{
float width = pdfImportedPage.Width;
float height = pdfImportedPage.Height;
if (pdfImportedPage.Rotation != 0)
{
PdfDictionary pageDict = reader.GetPageN(documentPage);
pageDict.Put(PdfName.ROTATE, new PdfNumber(0));
}
if (width > height)
{
PdfDictionary pageDict = reader.GetPageN(documentPage);
pageDict.Put(PdfName.ROTATE, new PdfNumber(270));
}
}
This works great. The included PDFs rotated to portrait orientation if needed. The PDF prints correctly on my local printer.
This file is sent to a fulfillment house, and unfortunately, the landscape included files do not print properly when going through their printer and rasterization process. They use Kodak (Creo) NexRip 11.01 or Kodak (Creo) Prinergy 6.1. machines. The fulfillment house's suggestion is to: "generate a new PDF file after we rotate pages or make any changes to a PDF. It is as easy as exporting out to a PostScript and distilling back to a PDF."
I know iTextSharp doesn't support PostScript. Is there another way iTextSharp can rotate included PDFs to hold the orientation when rasterized?
First let me assure you that changing the rotation in the page dictionary is the correct procedure to achieve what you want. As far as I can see your code, there's nothing wrong with it. You are doing the right thing.
Unfortunately, you are faced with a third party product over which you have no control that is not doing the right thing. How to solve this?
I have written an example called IncorrectExample. I have named it that way because I don't want it to be used in a context that is different from yours. You can safely ignore all the warnings I added: they are not meant for you. This example is very specific to your problem.
Please try the following code:
public void manipulatePdf(String src, String dest)
throws IOException, DocumentException {
// Creating a reader
PdfReader reader = new PdfReader(src);
// step 1
Rectangle pagesize = getPageSize(reader, 1);
Document document = new Document(pagesize);
// step 2
PdfWriter writer
= PdfWriter.getInstance(document, new FileOutputStream(dest));
// step 3
document.open();
// step 4
PdfContentByte cb = writer.getDirectContent();
for (int i = 1; i <= reader.getNumberOfPages(); i++) {
pagesize = getPageSize(reader, i);
document.setPageSize(pagesize);
document.newPage();
PdfImportedPage page = writer.getImportedPage(reader, i);
if (isPortrait(reader, i)) {
cb.addTemplate(page, 0, 0);
}
else {
cb.addTemplate(page, 0, 1, -1, 0, pagesize.getWidth(), 0);
}
}
// step 4
document.close();
reader.close();
}
public Rectangle getPageSize(PdfReader reader, int pagenumber) {
Rectangle pagesize = reader.getPageSizeWithRotation(pagenumber);
return new Rectangle(
Math.min(pagesize.getWidth(), pagesize.getHeight()),
Math.max(pagesize.getWidth(), pagesize.getHeight()));
}
public boolean isPortrait(PdfReader reader, int pagenumber) {
Rectangle pagesize = reader.getPageSize(pagenumber);
return pagesize.getHeight() > pagesize.getWidth();
}
I have taken the pages.pdf file as an example. This file is special in the sense that it has two pages in landscape that are created in a different way:
one page is a page of which the width is smaller than the height (sounds like it's a page in portrait), but as there's a /Rotate value of 90 added to the page dictionary, it is shown in landscape.
the other page isn't rotated, but it has a height that is smaller than the width.
In my example, I am using the classes Document and PdfWriter to create a copy of the original document. This is wrong in general because it throws away all interaction. I should use PdfStamper or PdfCopy instead, but it is right in your specific case because you don't need the interactivity: the final purpose of the PDF is to be printed.
With Document, I create new pages using a new Rectangle that uses the lowest value of the dimensions of the existing page as the width and the highest value as the height. This way, the page will always be in portrait. Note that I use the method getPageSizeWithRotation() to make sure I get the correct width and height, taking into account any possible rotation.
I then add a PdfImportedPage to the direct content of the writer. I use the isPortrait() method to find out if I need to rotate the page or not. Observe that the isPortrait() method looks at the page size without taking into account the rotation. If we did take into account the rotation, we'd rotate pages that don't need rotating.
The resulting PDF can be found here: pages_changed.pdf
As you can see, some information got lost: there was an annotation on the final page: it's gone. There were specific viewer preferences defined for the original document: they're gone. But that shouldn't matter in your specific case, because all that matters for you is that the pages are printed correctly.

Create PDF file with images in WinRT

How I can create PDF files from a list of image in WinRT. I found something similar for windows phone 8 here("Converting list of images to pdf in windows phone 8") But I am looking for a solution for windows 8. If anyone of having knowledge about this please share your thoughts with me.
Try http://jspdf.com/
This should work on WinJS, but I haven't tested it. In a XAML app you can try to host a web browser control with a jsPDF-enabled page.
ComponentOne has now released the same PDF library that they had in Windows Phone for Windows Runtime. Tho it's not open source, of course.
Amyuni PDF Creator for WinRT (a commercial library) could be used for this task. You can create a new PDF file by creating a new instance of the class AmyuniPDFCreator.IacDocument, then add new pages with the method AddPage, and add pictures to each page by using the method IacPage.CreateObject.
The code in C# for adding a picture to a page will look like this:
public IacDocument CreatePDFFromImage()
{
IacDocument pdfDoc = new IacDocument();
// Set the license key
pdfDoc.SetLicenseKey("Amyuni Tech.", "07EFCD0...C4FB9CFD");
IacPage targetPage = pdfDoc.GetPage(1); // A new document will always be created with an empty page
// Adding a picture to the current page
using (Stream imgStrm = await Windows.ApplicationModel.Package.Current.InstalledLocation.OpenStreamForReadAsync("pdfcreatorwinrt.png"))
{
IacObject oPic = page.CreateObject(IacObjectType.acObjectTypePicture, "MyPngPicture");
BinaryReader binReader = new BinaryReader(imgStrm);
byte[] imgData = binReader.ReadBytes((int)imgStrm.Length);
// The "ImageFileData" attribute has not been added yet to the online documentation
oPic.AttributeByName("ImageFileData").Value = imgData;
oPic.Coordinates = new Rect(100, 2000, 1200, 2000);
}
return pdfDoc;
}
Disclaimer: I currently work as a developer of the library
For an "open source" alternative it might be better for you to rely on a web service that creates the PDF file using one of the many open source libraries available.
I think this may help you if you want to convert an image (.jpg) file to a PDF file.
Its working in my lab.
string source = "image.jpg";
string destinaton = "image.pdf";
PdfDocument doc = new PdfDocument();
doc.Pages.Add(new PdfPage());
XGraphics xgr = XGraphics.FromPdfPage(doc.Pages[0]);
XImage img = XImage.FromFile(source);
xgr.DrawImage(img, 0, 0);
doc.Save(destinaton);
doc.Close();
Thanks.

Adding a dynamic image to a PDF using ColdFusion and iText

I pieced together some code to insert a dynamic image into a PDF using both ColdFusion and iText, while filling in some form fields as well. After I got it working and blogged about it, I couldn't help but think that there might be a better way to accomplish this. I'm using the basic idea of this in a production app right now so any comments or suggestion would be most welcomed.
<cfscript>
// full path to PDF you want to add image to
readPDF = expandpath(”your.pdf”);
// full path to the PDF we will output. Using creatUUID() to create
// a unique file name so we can delete it afterwards
writePDF = expandpath(”#createUUID()#.pdf”);
// full path to the image you want to add
yourimage = expandpath(”dynamic_image.jpg”);
// JAVA STUFF!!!
// output buffer to write PDF
fileIO = createObject(”java”,”java.io.FileOutputStream”).init(writePDF);
// reader to read our PDF
reader = createObject(”java”,”com.lowagie.text.pdf.PdfReader”).init(readPDF);
// stamper so we can modify our existing PDF
stamper = createObject(”java”,”com.lowagie.text.pdf.PdfStamper”).init(reader, fileIO);
// get the content of our existing PDF
content = stamper.getOverContent(reader.getNumberOfPages());
// create an image object so we can add our dynamic image to our PDF
image = createobject(”java”, “com.lowagie.text.Image”);
// get the form fields
pdfForm = stamper.getAcroFields();
// setting a value to our form field
pdfForm.setField(”our_field”, “whatever you want to put here”);
// initalize our image
img = image.getInstance(yourimage);
// centering our image top center of our existing PDF with a little margin from the top
x = (reader.getPageSize(1).width() - img.scaledWidth()) - 50;
y = (reader.getPageSize(1).height() - img.scaledHeight()) / 2 ;
// now we assign the position to our image
img.setAbsolutePosition(javacast(”float”, y),javacast(”float”, x));
// add our image to the existing PDF
content.addImage(img);
// flattern our form so our values show
stamper.setFormFlattening(true);
// close the stamper and output our new PDF
stamper.close();
// close the reader
reader.close();
</cfscript>
<!— write out new PDF to the browser —>
<cfcontent type=”application/pdf” file = “#writePDF#” deleteFile = “yes”>
<cfpdf> + DDX seems possible.
See http://forums.adobe.com/thread/332697
I have made it in another way with itext library
I don´t want overwrite my existing pdf with the image to insert, so just modify the original pdf inserting the image, just insert with itext doesn´t work for me.
So, I have to insert the image into a blank pdf (http://itextpdf.com/examples/iia.php?id=59)
And then join my original pdf and the new pdf-image. Obtaining one pdf with several pages.
(http://itextpdf.com/examples/iia.php?id=110)
After that you can overlay the pdf pages with this cool concept
http://itextpdf.com/examples/iia.php?id=113