I'm trying to define a environment for code listings wrapped in a shadowbox and centered in the line. Using this code, I can generate the kind of output that I want:
\documentclass[twocolumn]{article}
\usepackage{listings}
\usepackage{fancybox}
\usepackage{lipsum}
\begin{document}
\lipsum[4]
\begin{center}
\shadowbox{%
\begin{lstlisting}[gobble=6]
line of code
line of code
\end{lstlisting}%
}
\end{center}
\lipsum[4]
\end{document}
This produces output like this:
My problem arises when trying to abstract this into an environment. I've seen the some related questions:
- How to center a listing? The answer in this question suggests using
tabular
environment to center the listing, which works, but in the present case, theshadowbox
serves the same purpose (being just big enough to hold the listing). - How to center a lstlisting In this question the
tabular
technique doesn't work, but the answer shows how to save the contents of the listing in anSbox
(fromfancybox
) and set it in aparbox
in acenterline
. - adjustbox and lstnewenvironment This question actually involves creating frames around listings, and seems to be the most relevant to my question. The answer depends on
adjustbox
, which supports a simple frame, but not the shadowbox from fancybox. - Why does pdfLaTeX fail when I try to use `begin{lstlisting}` inside a user-defined environment? The answer here points out that it's tough to define environments in which
verbatim
-like environments will appear, and so it's best to uselstnewenvironment
.
Based on these approaches, I've gotten as far as unsuccessfully trying to use lstnewenvironment
. Just trying to get a centered listing, as below, fails (error message follows):
\documentclass[twocolumn]{article}
\usepackage{listings}
\usepackage{fancybox}
\usepackage{lipsum}
\usepackage{adjustbox}
\lstnewenvironment{CenteredShadowboxListing}[1][]{%
\begin{center}%
\lstset{#1}%
}{%
\end{center}%
}
\begin{document}
\lipsum[4]
\begin{CenteredShadowboxListing}[gobble=2]
line of code
line of code
\end{CenteredShadowboxListing}
\lipsum[4]
\end{document}
This fails with the error:
! File ended while scanning use of \lst@BOLGobble@.
<inserted text>
\par
<*> mwe.tex
How can I define an environment that includes a code listing, puts a shadowbox around it, and centers the box?