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Beamer 中叠加层的相对顺序

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Beamer 中叠加层的相对顺序

我正在使用相对叠加层创建演示文稿。当叠加层的显示顺序与代码解析的beamer顺序不同时，事情就会变得困难（例如参见tex相对叠加）。

第一部分

考虑以下示例。理解出现的顺序并不容易，想出实现所需顺序的代码也不容易。代码越复杂，事情就越难处理。

请注意，我不关心覆盖层是否包含列表项或tikz元素或其他内容。这应该是一个通用的解决方案。

现在：

\documentclass{beamer}
\begin{document}
\begin{frame}
\begin{itemize}
\item<+(2)-> First item, appears third
\item<+(-1)-> Second item, appears first
\item<+(1)-> Third item, appears fourth
\item<+(-2)-> Fourth item, appears second
\end{itemize}
\end{frame}
\end{document}

我想知道是否有一种方法可以定义叠加层的顺序，而不考虑其在文档中的出现顺序。下面给出了一个可能的示例。

通缉（无法编译）

\documentclass{beamer}
\begin{document}
\begin{frame}
\begin{itemize}
\item<foo1> First item, appears third
\item<foo2> Second item, appears first
\item<foo3> Third item, appears fourth
\item<foo4> Fourth item, appears second
\end{itemize}
\setorder{foo2, foo4, foo1, foo3}
\end{frame}
\end{document}

第二部分

此外，我希望覆盖层也可以消失。请考虑以下命令。目的是第一个覆盖层显示标记为foo1和 的项目。第二个覆盖层显示标记为和 的foo3项目，等等。foo1foo2

\setorder{ {foo1, foo3}, {foo1, foo2}, {foo3, foo4}, {foo2, foo4} }

答案1

这并不是真正的符号覆盖规范，而是针对第一个问题的简单尝试：

\documentclass{beamer}
\usepackage{etoolbox}

\def\againframeorder<#1>#2{%
  \def\do##1{\againframe<##1>{#2}}
  \docsvlist{#1}%
}

\setbeamercovered{transparent}

\begin{document}
\begin{frame}<beamer:0>[label=foo]
  \begin{itemize}
    \item<1> First item, appears third
    \item<2> Second item, appears first
    \item<3> Third item, appears fourth
    \item<4> Fourth item, appears second
  \end{itemize}
\end{frame}

\againframeorder<2,4,1,3>{foo}

\end{document}

基本上，我们在这里使用绝对覆盖编号作为“符号”，但不发送相应的帧（<beamer:0>）。然后我们使用循环\againframe按预期顺序发送它们。

在此处输入图片描述

答案2

经过一段时间，我让“setorder”命令开始工作，这使得示例相对容易定义。我会尝试使用它，看看它是否有用。抱歉缩进不好。

我问了这个问题的扩展版本本网站。

\documentclass{beamer}
\usepackage{xstring}
\usepackage{etoolbox}
\usepackage{tikz}
\newcounter{mycounter}

% #1 is of the form <name>[=-|n], e.g. foo=- or foo=10 or foo
% Stores in #2 the overlay specification for <name> s.t. it can be appended to the content of <name>
\newcommand*{\getNewOverlayContent}[2]{%
    \getItemSpec{#1}{itemSpec}%
    \IfStrEq{\itemSpec}{-}{%
        \csedef{#2}{\arabic{beamerpauses}-}%
    }{%
        \IfStrEq{\itemSpec}{}{%
            \csedef{#2}{\arabic{beamerpauses}}%
        }{%
            \IfInteger{\itemSpec}{%
%               \mycounter=\
                \setcounter{mycounter}{\arabic{beamerpauses}}%
                \addtocounter{mycounter}{\itemSpec}%
                \addtocounter{mycounter}{-1}%
                \csedef{#2}{\arabic{beamerpauses}-\arabic{mycounter}}%
            }{%
                \PackageError{setorder}{Argument has illegal format}{Argument was #1}%
            }%
        }%
    }%
%   input: #1, itemspec:\itemSpec, beamervalue: \arabic{beamerpauses}, content: \csuse{#2} \\
}
% #1 is of the form 'foo=1' or 'foo=-' or 'foo'. 
% #2 Is the name of the macro which should hold the result
% This macro stores the part infront '=' (the name) in #2.
\newcommand*{\getItemName}[2]{% 
    \IfSubStr{#1}{=}{%
        \StrBefore{#1}{=}[\tmp]%
        \csdef{#2}{\tmp}%
    }{%
        \csdef{#2}{#1}% 
    }%
}
% #1 is of the form 'foo=1' or 'foo=-' or 'foo'. 
% #2 Is the name of the macro which should hold the result
% This macro stores the part behind '=' (the overlay spec) in #2. The stored part is empty iff there is no '=' in #1
\newcommand*{\getItemSpec}[2]{%
    \StrBehind{#1}{=}[\tmp]%
    \csdef{#2}{\tmp}%
}
% #2 is the name where content should be appended. 
% It has been ensured previously that #2 is a defined macro
% #1 is the content to append
% Depending on whether #2 is empty or not a (,) is added 
% before appending #1
\newcommand*{\appendToOverlaySpecification}[2]{%
    \IfStrEq{\csexpandonce{#2}}{}{%
        % #1 i.e. <name> is empty
        \cseappto{#2}{\csname#1\endcsname}%
    }{%
        \cseappto{#2}{,\csname#1\endcsname}%
    }%
}

\newcommand*{\setorderItem}[1]{%
    \getNewOverlayContent{#1}{overlaycontent}%
    \getItemName{#1}{cmdname}%
    \appendToOverlaySpecification{overlaycontent}{\cmdname}%
}

\newcommand*{\setorderList}[1]{%
    \forcsvlist{\setorderItem}{#1}%
    \stepcounter{beamerpauses}%
}
\newcommand*{\setorder}[1]{%    
    \clearNamesListofLists{#1}%
    \forcsvlist{\setorderList}{#1}%
}

% takes a list of lists of the form: {foo=1, bla},{gar=-} and then defines empty macros for each name
\newcommand*{\clearNamesListofLists}[1]{%
    \forcsvlist{    \clearNamesList}{#1}%
}
\newcommand*{\clearNamesList}[1]{%
    \forcsvlist{    \clearName}{#1}%
}
\newcommand*{\clearName}[1]{%
    \getItemName{#1}{cmdname}%
    \csdef{\cmdname}{}% 
}
\begin{document}
\begin{frame}{Each overlay one item}
\setorder{{seconditem},{fourthitem},{firstitem},{thirditem}}

\begin{itemize}
\item<\firstitem> First item, appears third
\item<\seconditem> Second item, appears first
\item<\thirditem> Third item, appears fourth
\item<\fourthitem> Fourth item, appears second
\end{itemize}
\end{frame}

\begin{frame}{More complex example}
\setorder{{seconditem=2},{fourthitem},{firstitem=-},{thirditem=-}}
\begin{itemize}
\item<\firstitem> First item, appears third, does not disappear
\item<\seconditem> Second item, appears first, stays 2 slides
\item<\thirditem> Third item, appears fourth, does not disappear
\item<\fourthitem> Fourth item, appears second, stays 1 slide
\end{itemize}
\begin{tikzpicture}
\node<\seconditem> (foo1) [draw] {For second item};
\node<\fourthitem> (foo2) [draw, below of=foo1] {For fourth item};
\node<\firstitem> (foo3) [draw, right of=foo1, node distance=3.5cm] {For first item};
\node<\thirditem> (foo4) [draw, below of=foo3] {For third item};
\end{tikzpicture}
\end{frame}
\end{document}

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