[Tex/LaTex] How to make a hyperlink cover the whole line in table of contents including the dots

Question

The linktoc=all option of hyperref package makes both the reference text and page number clickable hyperlinks. However, the dots are still not hyperlinks.
This is not very important but I'm asking out of curiosity to know if it is a limitation in hyperref, noting that MS Word & OpenOffice as well as other tools allow to have the dots clickable?

May be it's not recommended?

Answer 1

Hyperlinks in the table of contents (TOC) are generated by the \contentsline command defined in hyperref.sty. The linktoc=all option setting makes \contentsline add separate links to the title and page number. A third link can be applied to the leader between the title and page number by patching the appropriate leader-generating command locally using etoolbox. Enclosing the whole TOC entry in a hyperlink would be much tidier, but this is a relatively difficult problem.

For TOCs formatted by latex internals, the leader is generated by the command \@dottedtocline defined in latex.ltx. The following patch simply encloses the leader in a hyperlink pointing to the current TOC entry's location, which is passed as the fourth argument to \contentsline.

\documentclass{report}
\usepackage[linktoc=all]{hyperref}
\usepackage{etoolbox}

\makeatletter
\pretocmd{\contentsline}
  {\patchcmd{\@dottedtocline}
     {\leaders}
     {\hyper@linkstart{link}{#4}\leaders}
     {}
     {}%
   \patchcmd{\@dottedtocline}
     {\hfill}
     {\hfill\hyper@linkend}
     {}
     {}}
  {}
  {}
\makeatother

\begin{document}
\tableofcontents
\chapter{First Chapter} \pagebreak
\section{First Section} \pagebreak
\subsection{First Subsection}
\chapter{Second Chapter} \pagebreak
\section{Second Section} \pagebreak
\subsection{Second Subsection}
\end{document}

The result looks terrible with link borders, but not so bad with colorlinks=true.

This patch is general enough to work with TOCs formatted via package-defined user commands so long as the leader is generated by \@dottedtocline. KOMA-Script's tocstyle is one example of such a package - it redefines \@dottedtocline.

tocloft and memoir issue the command \cftdotfill instead of \@dottedtocline. The code below demonstrates a patch that will work for both the tocloft package and the memoir document class.

\documentclass{memoir}
\usepackage[linktoc=all]{hyperref}
\usepackage{etoolbox}

\makeatletter
\pretocmd{\contentsline}
  {\patchcmd{\cftdotfill}
     {\leaders}
     {\hyper@linkstart{link}{#4}\leaders}
     {}
     {}%
   \patchcmd{\cftdotfill}
     {\hfill}
     {\hfill\hyper@linkend}
     {}
     {}}
  {}
  {}
\makeatother

\setcounter{tocdepth}{2}
\renewcommand*{\cftdot}{\ensuremath{\ast}}
\renewcommand*{\cftsectionfont}{\itshape}
\renewcommand*{\cftsectionleader}{\cftdotfill{\cftsectiondotsep}}
\renewcommand*{\cftsubsectionfont}{\scshape}
\renewcommand*{\cftsubsectiondotsep}{9}
\renewcommand*{\cftsubsectionleader}{\cftdotfill{\cftsubsectiondotsep}}

\begin{document}
\tableofcontents
\chapter{First Chapter} \pagebreak
\section{First Section} \pagebreak
\subsection{First Subsection}
\chapter{Second Chapter} \pagebreak
\section{Second Section} \pagebreak
\subsection{Second Subsection}
\end{document}