[Tex/LaTex] Multicols inside Tcolorbox breaks page before long Multicols (and doesn’t listen to pageheight)

multicoltcolorbox

As can be shown when compiling the following MWE, the page-height (2inch) allows for 11 lines of text per page (cf. page 1), since Twelfth line and Thirteenth line are sent to page 2.

After those thirteen lines, I introduce another thirteen lines of text, but which are inside a Multicols environment.

Explanation of title: Multicols inside Tcolorbox breaks page before long Multicols

The annoying thing is that the Multicol-lines are not added immediately after the previous lines (i.e. First line (inside multicols) doesn't start after Thirteenth line, but instead is sent to the next page because the Multicol is "too long" to fit on the same page).

Explanation of title: Multicols inside Tcolorbox doesn't listen to pageheight

Then, one can notice that the lines inside the Tcolorbox actually don't break after 11 lines, but go well beyond that (cf. the lines overflowing on page 3).

Note: I suppose that these behavior are not specifically related to the Tcolorbox (but are instead endemic to Multicols). Anyway, the MWE shows how I figured out the issue, and at the same time the Tcolorbox can clarify some things visually (e.g. page-height).

\documentclass{article}

\usepackage{multicol}
\usepackage[a4paper, total={7in, 2in}]{geometry}
\usepackage[breakable]{tcolorbox}
\newcommand\tbox[1]{\begin{tcolorbox}[breakable]#1\end{tcolorbox}}
\begin{document}

\tbox{

First line\\
Second line\\
Third line\\
Fourth line\\ 
Fifth line\\
Sixth line\\
Seventh line\\
Eighth line\\
Tenth line\\
Eleventh line\\
Twelfth line\\
Thirteenth line\\

\begin{multicols}{2}

First line (inside multicol)\\
Second line (inside multicol)\\
Third line (inside multicol)\\
Fourth line (inside multicol)\\
Fifth line (inside multicol)\\
Sixth line (inside multicol)\\
Seventh line (inside multicol)\\
Eighth line (inside multicol)\\
Tenth line (inside multicol)\\
Eleventh line (inside multicol)\\
Twelfth line (inside multicol)\\
Thirteenth line (inside multicol)\\ \columnbreak

Next to first line (inside multicol)\\
Next to second line (inside multicol)\\
Next to third line (inside multicol)\\
Next to fourth line (inside multicol)\\
Next to fifth line (inside multicol)\\
Next to sixth line (inside multicol)\\
Next to seventh line (inside multicol)\\
Next to eighth line (inside multicol)\\
Next to tenth line (inside multicol)\\
Next to eleventh line (inside multicol)\\
Next to  twelfth line (inside multicol)\\
Next to thirteenth line (inside multicol)\\ 

\end{multicols}

}

\end{document}

Best Answer

since you want manual control over the lines anyway, I'd just do

\documentclass{article}

\usepackage{multicol}
\usepackage[a4paper, total={7in, 2in}]{geometry}
\usepackage[breakable]{tcolorbox}
\newcommand\tbox[1]{\begin{tcolorbox}[breakable]#1\end{tcolorbox}}
\newcommand\x[2]{%
\noindent\makebox[.5\textwidth][l]{#1}%
\makebox[.5\textwidth][l]{#2}%
}
\begin{document}

\tbox{

\x{%
First line (inside multicol)}{%
Next to first line (inside multicol)}

\x{%
Second line (inside multicol)}{%
Next to second line (inside multicol)}

\x{%
Third line (inside multicol)}{%
Next to third line (inside multicol)}

\x{%
Fourth line (inside multicol)}{%
Next to fourth line (inside multicol)}

\x{%
Fifth line (inside multicol)}{%
Next to fifth line (inside multicol)}

\x{%
Sixth line (inside multicol)}{%
Next to sixth line (inside multicol)}

\x{%
Seventh line (inside multicol)}{%
Next to seventh line (inside multicol)}

\x{%
Eighth line (inside multicol)}{%
Next to eighth line (inside multicol)}

\x{%
Tenth line (inside multicol)}{%
Next to tenth line (inside multicol)}

\x{%
Eleventh line (inside multicol)}{%
Next to eleventh line (inside multicol)}

\x{%
Twelfth line (inside multicol)}{%
Next to  twelfth line (inside multicol)}

\x{%
Thirteenth line (inside multicol)}{%
Next to thirteenth line (inside multicol)}

}

\end{document}

Related Solutions

[Tex/LaTex] how to make ragged bottoms of columns in multicols when preventing page breaks

The desired effect can be achieved using the \raggedcolumns macro:

\documentclass[10pt,notitlepage]{article}%
\setlength{\columnseprule}{0pt} %column thicnkess 
\setlength{\columnsep}{5.0pt}
\usepackage{lipsum}
\usepackage{multicol}
\usepackage{titlesec}
\titleformat{\section}{\large\bfseries}{\thesection}{1em}{}
\begin{document}
\begin{multicols}{3}
\raggedcolumns     %new code
\interlinepenalty=10000
\section{some section}
\lipsum[75]
\section{some section}
\lipsum[75]
\section{some section}
\lipsum[3]
\section{some section}
\lipsum[75]
\section{some section}
\lipsum[75]
\section{some section}
\lipsum[75]
\section{some section}
\lipsum[4]
\section{some section}
\lipsum[75]
\end{multicols}
\end{document}

enter image description here

[Tex/LaTex] Identify tcolorbox page breaks

The short answer is:

Secure the text parts which should not break by putting them into a minipage.
Put your separating rule into a construction with e.g. \cleaders or \xleaders. This will make the line vanish at box breaks.

The long answer uses \tcbline* from the current tcolorbox development (unpublished yet; will be in version 3.10). I put this as a patch into the following source code.

This \tcbline* vanishes at box breaks. Further, its style can be set with segmentation style. My example shows two variants.

From your question, I presume that you want to have the partial boxes closed:

\documentclass{article}
\usepackage[many]{tcolorbox}
\usepackage{lipsum}

\makeatletter

%%%% begin patch for tcolorbox older than 3.10 %%%%%
\def\tcb@draw@pseudo@segmentation#1{%
\begingroup\tcb@shield@externalize\begin{tikzpicture}%
  \path[use as bounding box] (0,{\the\dimexpr-\kvtcb@middle-\kvtcb@boxsep\relax})
     rectangle (\linewidth,{\the\dimexpr\kvtcb@middle+\kvtcb@boxsep\relax});
  \node[line width=0mm,inner sep=0mm,draw=none,fill=none,rectangle,
        name=segmentation,at={({\the\dimexpr-\kvtcb@boxsep-(#1)\relax},0)},right,%
        minimum width=\tcb@innerwidth,minimum height=\the\dimexpr\kvtcb@middle*2\relax]{};
  \tcb@drawlower@path%
\end{tikzpicture}\endgroup}

\def\tcbline@star#1{%
{\parskip\z@\par\nointerlineskip}%
\xleaders\vbox{\tcb@draw@pseudo@segmentation{#1}}\vskip\dimexpr(\kvtcb@middle+\kvtcb@boxsep)*2\relax%
{\parskip\z@\par\nointerlineskip}}

\def\tcbline@#1{%
{\parskip\z@\par\nointerlineskip}%
\tcb@draw@pseudo@segmentation{#1}%
{\parskip\z@\par\nointerlineskip}}

\def\tcbline{%
  \@ifstar{\iftcb@hasLower\tcbline@star{\kvtcb@leftlower}\else\tcbline@star{\kvtcb@leftupper}\fi}%
  {\iftcb@hasLower\tcbline@{\kvtcb@leftlower+\@totalleftmargin}\else\tcbline@{\kvtcb@leftupper+\@totalleftmargin}\fi}}
%%%% end patch for tcolorbox older than 3.10 %%%%%

\makeatother

\begin{document}

%%% Example with thick complete lines
\begin{tcolorbox}[breakable,
  enhanced standard,% for segmentation style
  segmentation style={solid,line width=0.5mm},
  ]
  \foreach \n in {1,...,10}
  {
    \begin{minipage}{\linewidth}
    \lipsum[\n]
    \end{minipage}
    \tcbline*
  }
\end{tcolorbox}

\clearpage

%%% Example with hrule style line (in red, for fun)
\begin{tcolorbox}[breakable,
  enhanced standard,% for segmentation style
  segmentation style={solid,line width=0.4pt,
    shorten >=5mm,shorten <=5mm,red},
  ]
  \foreach \n in {1,...,10}
  {
    \begin{minipage}{\linewidth}
    \lipsum[\n]
    \end{minipage}
    \tcbline*
  }
\end{tcolorbox}

\end{document}

First example part with thick lines:

Second example part with thin red (and shorter) lines:

Best Answer

Related Solutions

[Tex/LaTex] how to make ragged bottoms of columns in multicols when preventing page breaks

[Tex/LaTex] Identify tcolorbox page breaks

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