Last Updated: 05 Mar 2021 12:46 by ADMIN
Release LIB 2021.1.309 (9/3/2021)
Created on: 11 Feb 2021 15:20
Category: PDFViewer
Type: Bug Report
Displaying a blank page with some PDF-Files

Hi Telerik Support

We use your Telerik PDF-Viewer since your last Version "UI for WPF R1 2021" which supports Type 3 fonts.
Now the version runs productive by our customers. But after a day, they found some special PDFs that doesn't work quite right with your PDF-Viewer.

In the appendix you will find the PDf-Files as samples for the bugs that i'm describing.
Because of data privacy, the PDF-Files are cutted and cropped.
Also a demo project is appended (It could also be reproduced with the demo Progress Telerik WPF UI for th PDF-Viewer).

First Problem: Blank Page

Hint: It seems that only a few PDF-Files from a specific program seems to be a problem.

  1. Open Demo "WpfAppPdfViewer.exe"
  2. Open the file sample_1_blank_page.pdf(see appendix)
  3. You will see only a blank page
  4. Open the same PDF-File in another PDF-Reader like Adobe Reader and you will see a scan with an illegible stamp of an address

Second Problem: Displaying data delayed

  1. Open Demo "Progress Telerik UI for WPF"
  2. Open the file sample_2_delayed_display.pdf (see appendix)
  3. You will see only a blank page
  4. Wait approx. 5-10 sec. and you will see the content of the PDF-File.

I would be glad for a quick possible solution for our customer.

Best regards

Serge Schoop

Posted on: 15 Feb 2021 07:28

Hi Daniel,

Thanks for the detailed description and for sharing the files.

I have approved the issue and our developers will look into it. Unfortunately, I cannot suggest a workaround for this issue (the case with the first file).   

For the second case, I have logged a separate item. You can track its progress, subscribe to status changes, and add your comment to it here:PdfViewer: Handle the cases when the page is rendered slowly and the document appears empty.

I can not suggest a workaround for this issue as well.

I have updated your Telerik points for both issues. 

Should you have any other questions do not hesitate to ask.

Progress Telerik

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Posted on: 11 Feb 2021 15:25
In the second Problem, step by step description, you could also use the demo project appended: WpfAppPdfViewer