Why does \titleclass remove my sections from the TOC?

Question

I'm trying to define a \preface command that would be identical to \chapter except that

It should not increment \thechapter counter.
In the TOC, "Preface" should go where "Chapter N" would normally go.
In the footers, I want "Preface - {chapter title}" instead of "Chapter N - {chapter title}"

Since I'm using titlesec anyway, I figured I'd try out titleclass for the first time. The moment I added the preface titleclass, however, my section level entries disappeared from the TOC!

After a few hours of debugging, I'm not making any headway. Any idea what's going on here?

Here's a MWE:

\documentclass[oneside]{book}

\usepackage{blindtext}
\usepackage{titlesec}
\usepackage{titletoc}
\usepackage{hyperref}
\usepackage{xcolor}

% use arabic numbering throughout
\makeatletter
\renewcommand{\frontmatter}{\cleardoublepage \@mainmatterfalse}
\renewcommand{\mainmatter}{\cleardoublepage \@mainmattertrue}
\makeatother

%%%% begin preface defs %%%%

% see http://tex.stackexchange.com/a/17278/2041 and the titlesec manual
\titleclass{\preface}{top}[\part]

\newcounter{preface} % required when defining a new titleclass; accessible via \thepreface

\titleformat{\preface}
    {\huge\bfseries}{}{0em}{}

% TODO verify that these dimensions make sense
\titlespacing*{\preface}{0pt}{3.25ex plus 1ex minus .2ex}{1.5ex plus .2ex}

% see autoref in hyperref manual
\newcommand{\prefaceautorefname}{preface}

%%%% end preface defs %%%%

%\setcounter{secnumdepth}{2} % I'm not sure if this is appropriate

\setcounter{tocdepth}{1} % only go down to the section level in TOC

%%%% begin TOC formatting %%%%

\titlecontents{chapter}
              [3pt]
              {\addvspace{1pc}}%
              {\contentsmargin{0pt}%
               \bfseries\large%
               \llap{\makebox[1.5in]{%
                   {\color{gray}Chapter~\thecontentslabel}\hfill\textbf{\thecontentspage}\hspace{8pt}%
               }}%
              }
              {\contentsmargin{0pt}\large}
              {}
              [\addvspace{.5pc}]

\titlecontents{preface}
              [3pt]
              {\addvspace{1pc}}%
              {\contentsmargin{0pt}%
               \bfseries\large%
               \llap{\makebox[1.5in]{%
                   {\color{gray}Preface}\hfill\textbf{\thecontentspage}\hspace{8pt}%
               }}%
              }
              {\contentsmargin{0pt}\large}
              {}
              [\addvspace{.5pc}]

\titlecontents{section}
              [3pt]
              {\addvspace{1pc}}%
              {\contentsmargin{0pt}%
               \large
               \llap{\makebox[1.5in]{%
                   \hfill\textbf{\thecontentspage}\hspace{8pt}%
               }}%
              }
              {\contentsmargin{0pt}\large}
              {}
              [\addvspace{.5pc}]

%%%% end TOC formatting %%%%


\begin{document}

\frontmatter

\tableofcontents

\mainmatter

\preface{Will This Work?}
%\chapter{Perhaps This Will Work}

\Blindtext[2]

\section{Under The Preface}

\Blindtext[3]

\subsection{To The Subway}

\Blindtext[2]

\subsection{Then To A Submarine}

\Blindtext[2]

\chapter{My First Chapter}

\blindtext[1]

\section{First Section Under A Chapter}

\Blindtext[2]

\section{Secondi}

\Blindtext[2]

\section{Triad}

\Blindtext[3]

\chapter{How About Another Chapter}

\section{Woot}

\Blindtext[2]

\end{document}

try with \setcounter{tocdepth}{2} levels are changed: preface=0, chapter=1, section=2,... — touhami, Sep 05 '16 at 21:51
@touhami For some reason this then causes subsections to also appear in the TOC. — Alan Munn, Sep 05 '16 at 22:25
@AlanMunn you're right, thanks for pointing this, i'll try to see closer. — touhami, Sep 06 '16 at 18:09

egreg · Accepted Answer · 2016-09-07T07:52:54.633

I've always found \titleclass very mysterious.

You can solve this in a different way, by setting the preface in the frontmatter (but it's just for logical placement) as \chapter*, adding manually the needed bits.

\documentclass[oneside]{book}

\usepackage{blindtext}
\usepackage{xcolor}
\usepackage{titlesec}
\usepackage{titletoc}
\usepackage{hyperref}

% use arabic numbering throughout
\makeatletter
\renewcommand{\frontmatter}{\cleardoublepage \@mainmatterfalse}
\renewcommand{\mainmatter}{\cleardoublepage \@mainmattertrue}
\makeatother

%%%% begin preface defs %%%%
\makeatletter
\newcommand{\preface}[1]{%
  \chapter*{#1}%
  \addcontentsline{toc}{chapter}{\protect\numberline{\protect\preface}#1}%
  \chaptermark{#1}%
%  \vspace*{-6ex}% add if really wanted
}
\makeatother
\newcommand{\chapterorpreface}{%
  \expandafter\ifx\expandafter\preface\thecontentslabel
    Preface
  \else
    Chapter~\thecontentslabel
  \fi
}
%%%% end preface defs %%%%

\setcounter{tocdepth}{1} % only go down to the section level in TOC

%%%% begin TOC formatting %%%%

\titlecontents{chapter}
  [3pt]
  {\addvspace{1pc}}%
  {\contentsmargin{0pt}%
   \bfseries\large
   \makebox[0pt][r]{\makebox[1.5in]{%
     \textcolor{gray}{\chapterorpreface}\hfill\textbf{\thecontentspage}\hspace{8pt}%
   }}%
  }
  {\contentsmargin{0pt}\large}
  {}
  [\addvspace{.5pc}]

\titlecontents{section}
  [3pt]
  {\addvspace{1pc}}%
  {\contentsmargin{0pt}%
   \large
   \makebox[0pt][r]{\makebox[1.5in]{%
     \hfill\textbf{\thecontentspage}\hspace{8pt}%
   }}%
  }
  {\contentsmargin{0pt}\large}
  {}
  [\addvspace{.5pc}]

%%%% end TOC formatting %%%%

\begin{document}

\frontmatter

\tableofcontents

\preface{Will This Work?}

\Blindtext[2]

\section{Under The Preface}

\Blindtext[3]

\subsection{To The Subway}

\Blindtext[2]

\subsection{Then To A Submarine}

\Blindtext[2]

\mainmatter

\chapter{My First Chapter}

\blindtext[1]

\section{First Section Under A Chapter}

\Blindtext[2]

\section{Secondi}

\Blindtext[2]

\section{Triad}

\Blindtext[3]

\chapter{How About Another Chapter}

\section{Woot}

\Blindtext[2]

\end{document}

The \chapterorpreface macro examines the current \thecontentslabel and, if it is \preface, it just prints “Preface”.

A solution with \titleclass, where \preface is made the same level as \chapter, namely 0. I added also the support for bookmarks and headers.

\documentclass[oneside]{book}

\usepackage{blindtext}

\usepackage{xcolor}
\usepackage{titlesec}
\usepackage{titletoc}
\usepackage{hyperref}
\usepackage{bookmark} % better using this

% use arabic numbering throughout
\makeatletter
\renewcommand{\frontmatter}{\cleardoublepage \@mainmatterfalse}
\renewcommand{\mainmatter}{\cleardoublepage \@mainmattertrue}
\makeatother

%%%% begin preface defs %%%%

% see http://tex.stackexchange.com/a/17278/2041 and the titlesec manual
\titleclass{\preface}[0]{top}%[\part]

\newcounter{preface} % required when defining a new titleclass; accessible via \thepreface

\titleformat{\preface}{\huge\bfseries}{}{0em}{}

% TODO verify that these dimensions make sense
\titlespacing*{\preface}{0pt}{3.25ex plus 1ex minus .2ex}{1.5ex plus .2ex}

% see autoref in hyperref manual
\newcommand{\prefaceautorefname}{preface}
\makeatletter
\def\toclevel@preface{0}
\makeatother
\renewcommand{\prefacemark}[1]{%
  \markboth{\MakeUppercase{Preface}}{\MakeUppercase{Preface}}% or whatever
}
%%%% end preface defs %%%%

%\setcounter{secnumdepth}{2} % I'm not sure if this is appropriate

\setcounter{tocdepth}{1} % only go down to the section level in TOC

%%%% begin TOC formatting %%%%

\titlecontents{chapter}
              [3pt]
              {\addvspace{1pc}}%
              {\contentsmargin{0pt}%
               \bfseries\large%
               \llap{\makebox[1.5in]{%
                   {\color{gray}Chapter~\thecontentslabel}\hfill\textbf{\thecontentspage}\hspace{8pt}%
               }}%
              }
              {\contentsmargin{0pt}\large}
              {}
              [\addvspace{.5pc}]

\titlecontents{preface}
              [3pt]
              {\addvspace{1pc}}%
              {\contentsmargin{0pt}%
               \bfseries\large%
               \llap{\makebox[1.5in]{%
                   {\color{gray}Preface}\hfill\textbf{\thecontentspage}\hspace{8pt}%
               }}%
              }
              {\contentsmargin{0pt}\large}
              {}
              [\addvspace{.5pc}]

\titlecontents{section}
              [3pt]
              {\addvspace{1pc}}%
              {\contentsmargin{0pt}%
               \large
               \llap{\makebox[1.5in]{%
                   \hfill\textbf{\thecontentspage}\hspace{8pt}%
               }}%
              }
              {\contentsmargin{0pt}\large}
              {}
              [\addvspace{.5pc}]

%%%% end TOC formatting %%%%


\begin{document}

\frontmatter

\tableofcontents

\mainmatter

\preface{Will This Work?}
%\chapter{Perhaps This Will Work}

\Blindtext[2]

\section{Under The Preface}

\Blindtext[3]

\subsection{To The Subway}

\Blindtext[2]

\subsection{Then To A Submarine}

\Blindtext[2]

\chapter{My First Chapter}

\blindtext[1]

\section{First Section Under A Chapter}

\Blindtext[2]

\section{Secondi}

\Blindtext[2]

\section{Triad}

\Blindtext[3]

\chapter{How About Another Chapter}

\section{Woot}

\Blindtext[2]

\end{document}

Great! Any idea why specifically was going wrong with my code? I'm more interested in learning than achieving the target output. — splicer, Sep 06 '16 at 03:42
Also, in your second approach, it seems that commenting out the prefaceautorefname, toclevel@preface, and prefacemark stuff still produces the same result. What exactly does it accomplish? — splicer, Sep 06 '16 at 04:23
@splicer The definition of \prefaceautorefname doesn't seem to be essential; on the other hand, \toclevel@preface avoids a warning and \prefacemark fixes the headers (try without it and look at the headers). I just changed the \titleclass declaration, but I don't really get what problem there was, as changing tocdepth to 2 also listed subsections in the TOC. — egreg, Sep 06 '16 at 08:07
In your first solution, why wrap \chapter* and addcontentsline in a group? — splicer, Sep 07 '16 at 02:46
@splicer The remains of an experiment, I forgot to remove them — egreg, Sep 07 '16 at 07:51

Why does \titleclass remove my sections from the TOC?

1 Answers1