自动双列模式

Question

我正在尝试创建歌本文档类。每首歌曲都在自己的页面上。如果歌曲是常规大小（适合一页一列），我想实现歌曲页面为一列，但如果歌曲太长而无法适合一页一列，则歌曲页面为两列（所有这些都必须自动发生，无需歌本作者交互）。可以实现吗？如果可以，如何实现？

附言：请不要向我推荐其他歌曲集风格和类别，我已经搜索过但它们不能满足我的需求。

Answer 1

您可以先使用单列模式在里面排版歌曲\savebox，然后测量最终的大小。如果太大，则再次以双列模式排版。据我所知，没有用于此目的的软件包，但这可以很容易地进行编程。您可以使用例如包来收集环境内容environ。

environ这里有一个使用和 的示例实现multicol。请根据您的需要进行调整。我提供了两个带有虚拟文本的示例用法。

\documentclass{article}

\usepackage{environ}
\usepackage{multicol}

\newsavebox{\songbox}

\NewEnviron{song}{% can also have arguments
    \clearpage
    % Add song title, at as argument etc.
    %
    % The content is \BODY
    % Let's save it in normal single column mode:
    \savebox{\songbox}{%
    \begin{minipage}{\linewidth}%
        \BODY
    \end{minipage}%
    }%
    % To high? (Replace \textheight if required)
    % \ht = hight, \dp = depth, both together is the total height
    \ifnum\dimexpr\ht\songbox+\dp\songbox > \textheight
        % Typeset again in two column mode:
        \begin{multicols}{2}%
           \BODY
        \end{multicols}%
    \else
        % Size is already OK, so use the content of the saved box:
        \usebox{\songbox}%
    \fi
}

\begin{document}

\begin{song}
   A short song\\
   La la la la la \\
   A very short song indeed\\
   But this is a very long line to demonstrate that we are still in single column mode. In fact it is so long that it will be broken into two lines.
\end{song}

\begin{song}
   This is a long song\\
   This is a long song\\
   And this is a long line to show the two column mode.
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
   This is a long song\\
\end{song}

\end{document}