Latex: stretchable curly braces outside math

问题:

I am producing some latex beamer slides (but I think it is not a beamer specific question per se).

I have the following:

\begin{itemize}
\item Issue1
\item Issue2
\item Issue3
\end{itemize}

Now, I want to have a right curly brace (i.e. '}') behind the items spreading over issue1 and issue2. And of course I want to write something behind that curly brace.

In a perfect world I would write something like:

\begin{itemize}
\left .
\item Issue1
\item Issue2
\right \} One and Two are cool
\item Issue3
\end{itemize}

This does not work because I am not in a math environment and I can not put the whole snippet inside a math environment because itemize would not work in that case.

Is there a clean solution or a hack to produce my desired result?

Regards, Bastian.

回答1:

I'd use tikz and make an overlay.

First include the proper packages (you may not need to include tikz since this is a beamer question):

\usepackage{tikz}
\usetikzlibrary{decorations.pathreplacing}

Then when you make your list, give names to the places after each item:

\begin{itemize}
    \item Issue 1     
        \tikz[remember picture] \node[coordinate,yshift=0.5em] (n1) {}; 
    \item Issue 2
        \tikz[remember picture] \node[coordinate] (n2) {};
    \item Issue 3
\end{itemize}

(Note: I shifted the y value up by 1/2 of a line maybe more would be better.)

Because we used remember picture we can refer to these places in an overlay:

  \begin{tikzpicture}[overlay,remember picture]
      \path (n2) -| node[coordinate] (n3) {} (n1);
      \draw[thick,decorate,decoration={brace,amplitude=3pt}]
            (n1) -- (n3) node[midway, right=4pt] {One and two are cool};
  \end{tikzpicture}

The path is there to deal with items that do not have the same width. This edit comes from ESultanik's answer.

The result is:

Side note: You can remove all of the remember picture options and add the following to automatically add remember to all pictures:

\tikzstyle{every picture}+=[remember picture]

回答2:

You could (ab)use a table instead:

\documentclass{article}
\usepackage{multirow}

\begin{document}

\begin{tabular}{ll}

\textbullet Issue 1 & \multirow{2}{*}{{\LARGE \}} One and Two are cool} \\
\textbullet Issue 2                                                     \\
\textbullet Issue 3                                                     \\

\end{tabular}

\end{document}

produces:

removed dead Imageshack link

回答3:

Here is Geoffs code with some small adaptions (just for other beamer users)

\begin{frame}{Example}

\begin{itemize}
\item The long Issue 1
\tikz[remember picture] \node[coordinate,yshift=0.7em] (n1) {}; \\
spanning 2 lines


\item Issue 2
  \tikz[remember picture] \node[coordinate, xshift=1.597cm] (n2) {};
\item Issue 3

\end{itemize}

\visible<2->{
\begin{tikzpicture}[overlay,remember picture]
  \draw[thick,decorate,decoration={brace,amplitude=5pt}]
        (n1) -- (n2) node[midway, right=4pt] {One and two are cool};
\end{tikzpicture}
 } % end visible

\end{frame}

Ressult (2nd slide of that frame):

The adaptions are:

• added the visible command (because I think it is useful to blend in the brace later)
• made the items more complex so the use of xshift became necessary (I figured out the xshift value simply by try and error so thats a drop of bitterness) Edit 2018-12-23: manual try-and-error shifting can be overcome by using this method: (n1 -| n2) -- (n2) instead of (n1) -- (n2).

回答4:

One way to get around this would be to use a math environment like align, put the bullet points by hand (with \bullet ), and then use the resources of the math environment for big braces and such.

回答5:

I did something similar once. I let the list be in a column to the left, and in the right column, I did the $\right\}$-thing so that it was as tall as some \mbox or something (which I decided with \vphantom or something similar). Unfortunately I don't have time to dig it out... I actually don't have time to be at SO at all right now ;)

回答6:

I tried my idea, below. It doesn't work: unfortunately, the vboxes produced by the itemize environment all have width \textwidth.

The UI of my suggestion is nice, and by redefining \item it should be possible to get the item vboxes be of reasonable width. Or calculate a reasonable width for the vboxes containing the items. But since there are functional solutions already, I won't spend anymore time on this.

\documentclass{article}

\def\setgrouptext#1{\gdef\grouptext{#1}}
\newenvironment{groupeditems}{\begin{displaymath}\left.\vbox\bgroup\setgrouptext}{%
  \egroup\right\rbrace\hbox{\grouptext}\end{displaymath}}

\begin{document}

\begin{itemize}
\item Line 1
\begin{groupeditems}{Lines 2 and 3 together!}
\item Line 2
\item Line 3
\end{groupeditems}
\item Line 4
\end{itemize}

\end{document}