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Using method UsePdfPrinting() not allowing to print PDF documents


#1

Hello,


I attach you the screenshot. As you can see, the print button is disabled (if I am trying to print PDF document) so I can’t print the document.

Can you reproduce that?

Thank you.

#2

Hello Alexis,

We are sorry to hear that you have this issue. Can you tell us a bit more about this issue? It occurs especially with PDF documents, or with others too? On the screenshot we also see watermark and rotated page. The issue is still present, when these factors (rotating and watermarking) are disabled? We also don’t see a standard GUI on the screenshot, have you disabled it?

Can you, please, provide us a source code of the GroupDocs.Viewer widget? And also to describe sequence of your actions?

Thanks.


#3

Hello Denis,


About your questions:
  • It ocurrs only with PDF.
  • PDF with/without watkermark or with/whitout rotated pages.
What do you mean about the standard GUI?

The GroupDocs.Viewer widget sent via email.

Thank you.

#4

Hello Alexis,

Thanks for providing us the code, but we unfortunately cannot reproduce the issue using your source code. About the “standard GUI” phrase, which I’ve asked - the question is removed now; I figured out that you are using the Google Chrome, and a Google Chrome toolbar is present on a screenshot.

I used Google Chrome and “Print” button is active, as you can see from the screenshot below.

I googled a little and found out that this issue may be caused by different reasons like plugins and so on. So I want to ask you the next things and then report the results here:
1. In the Google Chrome are you able to print the document using a “Ctrl + Shift + P” combination?
2. What about other browsers? Are you able to reproduce this issue there and if yes, then how it looks like?

Thanks and waiting for your reply.


#5

Hello Denis,


Thanks for your answers.

About your questions:
  1. No, I’m not able.
  2. Yes, I am (attachs included)



#6

Hello Alexis,

Thanks for your reply, now we can see, that this issue is not related with specific browser, but rather with all browsers.

We suspect that this issue may be related to the some specific system configuration and settings, which are not associated with the GroupDocs.Viewer. It is very unusual and non-believable, that GroupDocs.Viewer is a reason of such issue. Because, in fact, when the option “.UsePdfPrinting()” is enabled and you click the “Print” button, server returns pure PDF document with “application/pdf” content type, and nothing more. And from this moment, when a browser has obtained a PDF-version of the document from the server, the GroupDocs.Viewer and a server at all have nothing to do with what happens next. All that will happen at the next step depends on how the browser will handle the PDF file.

To verify this you can try to open the same page on another machine, for example (but you should be careful - that another computer can be configured also with the same option). Or you can try to print some another (not related with the GroupDocs.Viewer) PDF file from the browser.

Thanks.


#7

Hi Denis,
It is possible to get the url for the pdf that is printed using the “UsePdfPrinting” function?
We are thinking on ask you to do or do it ourself, an applet that prints this pdf.


Please send me your comments.

Thanks,
Juan


#8

Hello Juan,

I’m sorry but, to be honest, I cannot understand, which URL you need. maybe, there is some misunderstanding; now I’ll try to explain and answer, and then you will clarify your question.

There are two printing modes: standard printing (or HTML-printing) and PDF-printing. These modes are controlled by the “UsePdfPrinting” method:
.UsePdfPrinting(false)” (or method is not specified) - standard mode;
".UsePdfPrinting(true)" - PDF mode.

Standard mode
When you click the “Print” button on the toolbar or use a groupdocsViewer(“printDocument”)” JavaScript method from the GroupDocs.Viewer widget, GroupDocs.Viewer sends an asynchronous POST-request to the server-side using the URL “http://domain-name/document-viewer/GetPrintableHtmlHandler”. The POST request parameters dictionary contains some specific data like the document name, rendering mode, watermark and its specifications (if watermark is present) and so on - you can investigate this by yourself. Server obtains this request, generates on server-side a special HTML-version of the document, which is designated especially for the printing, and returns a JSON array to the client-side. Each element in this JSON array represents a single page of the document and contains one link like “http://domain-name/document-viewer/GetDocumentPageImageHandler?path=candy.pdf&width=&quality=100&usePdf=True&watermarkText=&watermarkColor=&watermarkPosition=Diagonal&watermarkFontSize=0&useHtmlBasedEngine=False&rotate=False&pageIndex=0”. GroupDocs.Viewer on the client-side builds a HTML-version for the printing based on these links, invokes a “window.print();” JavaScript method and passes the HTML-version for the printing into this method. Browser opens a “Printing” modal window, where you can select printer, page range, number of copies and so on - it depends on the specific browser.

PDF-mode
When you click the “Print” button on the toolbar or use a groupdocsViewer(“printDocument”)” JavaScript method from the GroupDocs.Viewer widget, GroupDocs.Viewer sends an asynchronous GET-request to the server-side using the URL like “http://domain-name/document-viewer/GetPdfWithPrintDialogHandler?path=candy.pdf&useHtmlBasedEngine=true&supportPageRotation=true” (GET-parameters contains different document-related data, as you can see). The server obtains this request and returns a PDF-version of the original document (or the original document, if it is a PDF) to the client-side with “Content-Type: application/pdf” response header. If browser is able to display the PDF document, it displays it (for example, if you have installed an Adobe Reader, all your browsers should be able to display PDF files). If browser cannot display a PDF, it shows a “Save file” modal window - this behaviour depends on the specific browser.

That’s why the previously reported problems with disabled “Print” buttons are not related to the GroupDocs.Viewer - it simply cannot control your printers and computers, enabling or disabling them. It simply calls the “window.print();” JavaScript method in case of standard printing mode or returns a PDF file in case of the PDF-mode. And that’s all.

Thanks and waiting for your reply.

#9

Hi Denis,
i was referring to the pdf-mode, as you say when you click the “Print” button the viewer, uses an url like “http://domain/viewersite/document-viewer/GetPdfWithPrintDialogHandler?path=temp\S\106_1.docx&watermarkText=+&watermarkColor=0&watermarkPosition=TopCenter&watermarkFontSize=0&useHtmlBasedEngine=true&supportPageRotation=true” to get the pdf.
To get off the problems of depend if the browser is able to display the PDF document, we are thinking on use another web page that will have an applet that will use this url to print the pdf directly.

In your opinion, how do you think about this solution?
I’ll would be glad to hear your comments.

Thank,
Juan


#10

Hello Juan,

Well, if you do need such functionality, you are welcome to use it. This link is idempotent, it “holds” a GET-request, and its result depends on the GET-parameters, and only on them. By using this link and passing the specific desired parameters like document name, you can obtain a PDF-version of any existent document. The only requirement - the cache should exist for the requested document. It is not necessary to open the document just before using this link; the document can be opened a long time ago and even by another user. In other words, the “GetPdfWithPrintDialogHandler” HTTP-handler cannot generate the PDF-version of a document, it can only deliver the previously generated file.

But, again, this link will only provide you the PDF-version of the document and nothing more. How to print this document - depends on you and your environment. For example, you can save this PDF, open in Adobe Reader (for example) and print. Or print from the browser, if browser can open a PDF.

Thanks.


#11

Hi Denis,

how are you?

It is possible for you to implement an api function to return this url, relative to the document displayed by the viewer?

My idea is, having the document opened by the viewer. Invoke this new function and get the url, and then, print the document.

Thanks,
Juan


#12

Hi,
I’ve managed to get the url using:

$("#container").groupdocsViewer(“getViewModel”).pdfPrintUrl

Thanks,
Juan


#13

Hello Juan,

Sure, we will review this request and will let you know about this.

Thanks.