Create version of report with local links to referenced articles

Question

I have the following set-up in mind, and I hope someone could help me achieve this:

I cite entries from my .bib file. I use the hyperref package (manual) with the pagebackref option set to true, so when I run pdfLaTeX all my references point to the corresponding bibliography option and I can jump back to my reference.

During report writing this behaviour is not useful for me. I would rather have it such that a reference click would open the PDF file of the clicked article. So when I have a BibTex entry with label {mylittlepony}, I cite this with

Everybody loves chocolate \cite{mylittlepony}.

In the PDF file it says:

Everybody loves chocolate [1].

Now if I click the [1] a file called mylittlepony.pdf should open from a pre-defined folder.

This behaviour should only occur during report writing. When I want to generate the document for other people the original hyperref behaviour should occur, so an additional option should be set for the hyperref package. This is a hard restriction.

I want this to work with TexWorks' (Windows) integrated PDF-viewer as I like the syncTex functionality. This is not a hard restriction. If there are other ways of keeping a simple editor, syncTex and the custom behaviour described above I would go for that.

I tried using the \href function to reference to local files, but this does not work in the integrated PDF-viewer, only in Acrobat Reader X.

Answer 1

You can use the following code:

\usepackage{ifdraft}
\ifdraft{\let\obibcite=\bibcite}{}
\usepackage[final]{hyperref}
\makeatletter
\ifdraft{
  \let\bibcite=\obibcite
  \def\@citex[#1]#2{\leavevmode
  \let\@citea\@empty
  \@cite{\@for\@citeb:=#2\do
  {\@citea\def\@citea{,\penalty\@m\ }%
  \edef\@citeb{\expandafter\@firstofone\@citeb\@empty}%
  \if@filesw\immediate\write\@auxout{\string\citation{\@citeb}}\fi
  \hyper@linkurl{% NEW
  \@ifundefined{b@\@citeb}{\hbox{\reset@font\bfseries ?}%
  \G@refundefinedtrue
  \@latex@warning
  {Citation `\@citeb' on page \thepage \space undefined}}%
  {\@cite@ofmt{\csname b@\@citeb\endcsname}}}%
  {\@citeb.pdf}% NEW
  }}{#1}}
}{}
\makeatother

It uses the ifdraft package to determine whether the document is in draft mode. If so, the original definition of the \bibcite macro is saved, then hyperref is loaded (with the final option, otherwise no links would be generated at all). Now, we restore the hyperref-free version of \bibcite to remove the default link to the bibliography which is normally produced. Instead, we patch the internal LaTeX command \@citex to generate a hyperlink to the corresponding PDF file - so \cite{mylittepony} links to mylittlepony.pdf now.

Example code:

\documentclass[draft]{article}

\usepackage{ifdraft}
\ifdraft{\let\obibcite=\bibcite}{}
\usepackage[final]{hyperref}
\makeatletter
\ifdraft{
  \let\bibcite=\obibcite
  \def\@citex[#1]#2{\leavevmode
  \let\@citea\@empty
  \@cite{\@for\@citeb:=#2\do
  {\@citea\def\@citea{,\penalty\@m\ }%
  \edef\@citeb{\expandafter\@firstofone\@citeb\@empty}%
  \if@filesw\immediate\write\@auxout{\string\citation{\@citeb}}\fi
  \hyper@linkurl{% NEW
  \@ifundefined{b@\@citeb}{\hbox{\reset@font\bfseries ?}%
  \G@refundefinedtrue
  \@latex@warning
  {Citation `\@citeb' on page \thepage \space undefined}}%
  {\@cite@ofmt{\csname b@\@citeb\endcsname}}}%
  {\@citeb.pdf}% NEW
  }}{#1}}
}{}
\makeatother

\begin{document}
Everybody loves chocolate \cite{mylittlepony}.

\begin{thebibliography}{1}
\bibitem{mylittlepony}
My bibliography entry.
\end{thebibliography}
\end{document}

(The environment thebibliography is solely for making a self-contained example, you can replace it with your own \bibliography{...} without harm.)

This code is tested with TeXworks 0.4.3 on Windows 7, where it opens mylittlepony.pdf with the default PDF viewer. Note that it may not work with other versions of TeXworks or different operating systems: Unfortunately, the internal viewer has a very limited support for hyperlinks - direct file links are apparently not working, so this solution creates an URL link instead, which works for TeXworks, may break with other viewers on the other hand.