Problem loading .pdf file from qrc

[el33t]

Hi,

I have a qrc resource file which contains some image, htm and pdf file. I'm able to load the images and htm files perfectly without any problem, however whenever I try to load the PDF files(using poppler), I get the following error :

Couldn't open file 'qrc:/file/money.pdf' : Invalid argument "

HOWEVER,

When I open the PDF file from outside the resource, it works flawlessly.

Below is a code snippet of what I'm trying to do :

........
txt = new QWebView(this);
QUrl url("qrc:/file/00101.htm");  //THE .HTM FILE LOADS FLAWLESSLY
 txt->load(url);
 
Poppler::Document *document = Poppler::Document::load("qrc:/file/money.pdf");   // DOESEN'T WORK IF I LOAD FROM RESOURCE
 
Poppler::Document *document = Poppler::Document::load("C:/Users/el33t/Documents/QT EXPERIMENTS/Pro1/file/money.pdf"); // WORKS FLAWLESSLY IF I LOAD IT EXTERNALLY.

........
txt = new QWebView(this);
QUrl url("qrc:/file/00101.htm");  //THE .HTM FILE LOADS FLAWLESSLY
 txt->load(url);

Poppler::Document *document = Poppler::Document::load("qrc:/file/money.pdf");   // DOESEN'T WORK IF I LOAD FROM RESOURCE

Poppler::Document *document = Poppler::Document::load("C:/Users/el33t/Documents/QT EXPERIMENTS/Pro1/file/money.pdf"); // WORKS FLAWLESSLY IF I LOAD IT EXTERNALLY.

To copy to clipboard, switch view to plain text mode 

Any help would be greatly appreciated.

Regards,

[DanH]

If the load operation is being done by the PDF viewer then likely it doesn't know how to access something from a QRC.

And putting large files in a QRC is a bad idea anyway -- it's really only intended for small files. Putting large files in a QRC increases the amount of main store occupied by your program, makes it load slower, and generally hoses things up.

[el33t]

And putting large files in a QRC is a bad idea anyway -- it's really only intended for small files. Putting large files in a QRC increases the amount of main store occupied by your program, makes it load slower, and generally hoses things up.

But then using resources is the only way(as far as I know) of 'hiding' my files so that people don't just leech them off when I release my program.

[DanH]

They can be placed in the private directory of the app. This isn't perfectly secure, but they're inaccessible to any on-phone tools.

[wysota]

But then using resources is the only way(as far as I know) of 'hiding' my files so that people don't just leech them off when I release my program.

Security through obscurity is never a good idea. And extracting this pdf file from your binary (or directly from memory) is pretty simple so if one really wants to do it, you won't stop him.

[el33t]

ummm... I already had a discussion regarding this...so let's just stick to the topic's purpose.

What's wrong with my program? Why isin't the pdf loading from the .qrc ?

Regards

[ChrisW67]

You have already been told why Poppler, which knows nothing about the Qt mechanism for embedding resources or the pseudo-filesystem used to access them, cannot open the embedded file using a pseudo file name.

If you really must have the PDF embedded then you could:

• Use the Poppler API call that loads from data in-memory and use that after reading the resource into a QByteArray: Poppler::Document::loadFromData().
• Copy the file out of resources into a temporary file and then open that with Poppler::Document::load()

Incidentally, you refer to a "file" in the resources as ":/path/to/file"... the "qrc:" scheme is for use in URLs.

[el33t]

You have already been told why Poppler, which knows nothing about the Qt mechanism for embedding resources or the pseudo-filesystem used to access them, cannot open the embedded file using a pseudo file name.

If you really must have the PDF embedded then you could:

• Use the Poppler API call that loads from data in-memory and use that after reading the resource into a QByteArray: Poppler:ocument::loadFromData().
• Copy the file out of resources into a temporary file and then open that with Poppler:ocument::load()

Incidentally, you refer to a "file" in the resources as ":/path/to/file"... the "qrc:" scheme is for use in URLs.

WHOA!!! I followed your advice of reading the pdf into a array and voila! it works!! Thanks A LOT!

Also, I'd like to thanks the rest others who participated in this thread.

Anyways, if anyone else facing a similar problem want to see what code modification/addition I did to resolve the issue, here is the snippet :

QFile f;
  f.setFileName(":/file/money.pdf");
  f.open(QIODevice::ReadOnly);
  QByteArray pdf=f.readAll();
 
 
  Poppler::Document *document = Poppler::Document::loadFromData(pdf);

QFile f;
  f.setFileName(":/file/money.pdf");
  f.open(QIODevice::ReadOnly);
  QByteArray pdf=f.readAll();


  Poppler::Document *document = Poppler::Document::loadFromData(pdf);

To copy to clipboard, switch view to plain text mode 

Regards...