[Tex/LaTex] How to prevent a page break between section title and colored rule

colorpage-breakingrulessectioningtitlesec

I use \usepackage[explicit]{titlesec} to customize the design of my sections, subsections…
In particular, i have :

\titleformat{\section}%
{\large\sffamily\bfseries}%
{My Section \arabic{section} }%
{0.5em}%
{#1}% \\ \hspace*{-1.5cm}
[{\color{blue}\titlerule[2.5pt]}]

where the {\color{blue}\titlerule[2.5pt]} produces an underline. The problem is, that a page breaking can happen just after the section title, and the line would appear on the next page. Is there a way to prevent that ?

EDIT : Minimal Example:

\documentclass[12pt]{article}
\usepackage[explicit]{titlesec}
\usepackage[dvipsnames]{xcolor}

\titleformat{\section}%
{\large\sffamily\bfseries}%
{Section \arabic{section}}%
{0.5em}%
{#1}% \\ \hspace*{-1.5cm}
[{\color{blue}\titlerule[2.5pt]}]

\begin{document}

\section{titre1}
blabla  
\vspace{16cm}\\
blabla  
\section{titre2}
blabla blabla 
\end{document}

Best Answer

Replace {\color{blue}<rule definition>} with \textcolor{blue}{<rule definition>}.

\documentclass[12pt]{article}
\usepackage[explicit]{titlesec}
\usepackage[dvipsnames]{xcolor}

\titleformat{\section}%
{\large\sffamily\bfseries}%
{Section \arabic{section}}%
{0.5em}%
{#1}% \\ \hspace*{-1.5cm}
[\textcolor{blue}{\titlerule[2.5pt]}]

\begin{document}

\section{titre1}
blabla  
\vspace{16cm}\\    blabla  
\section{titre2}
blabla blabla 
\end{document}

EDIT: Note that this solution produces unwanted additional vertical space between title and underline. See Strange behaviour of titlesec, with colored titlerule and particularly egreg's answer for a solution to this follow-up problem.

Related Solutions

[Tex/LaTex] How to put a line above a section heading and prevent a page break between

To prevent a page break, you could use a minipage environment. The samepage environment could also be used. Further there's the needspace package: the command \needspace requests a user-defined amount of space, otherwise it inserts a page break. That can be useful for headings because they should also not be right at the end of the page.
You can insert a \raggedright command, for instance directly before \@startsection.

There are packages you could use:

titlesec is very good for customizing headings
sectsty is also useful, for instance for 2. the command \sectionfont{\raggedright} would be sufficient.

Since the needspace package offers a nice solution and might cause less problems, I recommend to use its \needspace command. Since I know you don't like to load additional packages, here's a minimal example with only the copied \needspace command for a demonstration:

\documentclass{article}
\makeatletter
\newcommand{\needspace}[1]{\begingroup\setlength{\dimen@}{#1}%
  \vskip\z@\@plus\dimen@ \penalty -100\vskip\z@\@plus -\dimen@
  \vskip\dimen@ \penalty 9999\vskip -\dimen@\endgroup}% from needspace.sty
\def\section{%
    \needspace{3\baselineskip}%
    \vskip 1.2ex%
    \hrule height 1pt%
    \@startsection{section}{1}{\z@}{-1pt}{1pt}{%
      \raggedright\normalfont\large\bfseries}%
}
\makeatother
\begin{document}
Text
\vspace{.93\textheight}
\section{This is a very, very long heading just to test the justification}
\end{document}

Output:

alt text

To verify that it works like desired:

if you remove the line \needspace{3\baselineskip}% there would be a page break between the top line and the section title
if you remove \raggedright the word justification would be hyphenated.

[Tex/LaTex] How to prevent page break between two section headings

The problem is that \color{MMIblue} inserts a whatsit that disrupts the mechanism for disallowing page breaks after sectional titles.

Use

\newcommand\section{%
  \@startsection{section}{1}
    {\headerindent}%
    {-3.5ex \@plus -1ex \@minus -.2ex}%
    {2ex \@plus.2ex}%
    {\headingfont\Large\textcolor{MMIblue}}}

which works because the last instruction in the sixth argument to \@startsection reads the section title (with the number) as a braced group, which can then be interpreted by \textcolor as its second argument.

Best Answer

Related Solutions

[Tex/LaTex] How to put a line above a section heading and prevent a page break between

[Tex/LaTex] How to prevent page break between two section headings

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