我尝试在 4 张幻灯片中显示框架。前 2 张还可以，但我无法使用两张幻灯片显示表格。第一列的内容显示正确 - 仅在第 4 张幻灯片上，但此列周围的边框仍显示
\documentclass[12pt]{beamer}
%\documentclass[12pt,handout]{beamer}
\usepackage{multirow} %Used for tables with merged cells
\usepackage{collcell} %pdflatex.exe hangs without this one
\begin{document}
\begin{frame}{Communication Models}
\begin{itemize}[<+->]
\item OSI
\item TCP/IP
\end{itemize}
\onslide<3->
\begin{center}
%Works almost fine, but first column should disappear fully (not just text)
\begin{tabular}{|>{\onslide<4->}l<{\onslide<3->}|l|l|l|}
\hline
\textbf{Mnemonic}& \textbf{\#} & \textbf{OSI} & \textbf{TCP/IP} \\ \hline
All & 7 & Application & \multirow{3}{*}{Application} \\ \cline{1-3}
People & 6 & Presentation & \\ \cline{1-3}
Seem & 5 & Session & \\ \hline
To & 4 & Transport & Transport \\ \hline
Need & 3 & Network & Internet \\ \hline
Data & 2 & Data Link & \multirow{2}{*}{Link Access} \\ \cline{1-3}
Processing & 1 & Physical & \\ \hline
\end{tabular}
\end{center}
\end{frame}
\end{document}
代替：
\begin{tabular}{|>{\onslide<4->}l<{\onslide<3->}|l|l|l|}
我尝试使用：
\begin{tabular}{>{\onslide<4->}|l<{\onslide<3->}|l|l|l|}
\begin{tabular}{ \ifnum\slideno>3 | \fi >{\onslide<4->}l<{\onslide<3->}|l|l|l|}
但第一个版本给出：
! Package array Error: >{..} at wrong position: token ignored.
第二：
! Package array Error: Illegal pream-token (\ifnum): `c' used.
是否可以让几张幻灯片上的第一列完全隐藏（包括边框）？
解决方案，基于 Piet 的答案 (UPD2)
更新的解决方案（UPD3）使用与页面无关的slideinframe计数器，对每一帧分别进行计数
该解决方案用于\newcolumntype{G}第一列，它不会出现在幻灯片 3 中，但会出现在幻灯片 4 和讲义中。
% Add line below to preamble
\def\Gobble#1\EndGobble{}
% UPD3: 3 lines below define slide counter within a frame (found here: http://tex.stackexchange.com/a/120940/119704)
\makeatletter
\def\c@slideinframe{\beamer@slideinframe}
\makeatother
...
% Add lines below to body (before tabular, and edit tabular definition)
% Next line is to show first column on handouts
\newcolumntype{G}{|l}
% Rules below hide first column on first 3 slides of beamer presentation, no influence on handouts
\only{beamer}{
% UPD3: Change "page" to "slideinframe"
%\ifnum\value{page}>3 \newcolumntype{G}{|l}\else
\ifnum\value{slideinframe}>3 \newcolumntype{G}{|l}\else
% I would be grateful if someone could describe the magic below :)
\newcolumntype{G}{@{}>{\Gobble}l<{\EndGobble}@{}}\fi
}
% Apply newcolumntype
\begin{tabular}{G|l|l|l|}
基于 samcarter 解决方法的解决方案 (UPD1)
绘制一个颜色与背景颜色相同的矩形此解决方案需要微调（矩形的位置和大小）
% Add line below to preamble:
\usepackage{tikz}
...
% Add lines to the end of frame:
\only<beamer>{
\vspace*{-4.7cm}
\begin{tikzpicture}
\begin{onlyenv}<3>
\draw [color=bg, fill=bg] (0,0) rectangle (3.67,4.3);
\end{onlyenv}
\end{tikzpicture}
}
\end{frame}
\end{document}
答案1
编辑：我已将其更改为稍微干净的解决方案\newcolumntype。
您不能将宏放入tabular必须在定义时展开的规范中。您必须使整begin{tabular}{...}行都具有条件性。然后您仍然需要吞掉第一列文本。
或者，定义一个新的列类型，以幻灯片编号为条件。以下是示例：
\documentclass[12pt]{beamer}
\usepackage{multirow} %Used for tables with merged cells
\usepackage{collcell} %pdflatex.exe hangs without this one
\def\Gobble#1\EndGobble{}
\begin{document}
\begin{frame}{Communication Models}
\begin{itemize}[<+->]
\item OSI
\item TCP/IP
\end{itemize}
\onslide<3-4>
\begin{center}
\only<3> {\newcolumntype{G}{@{}>{\Gobble}l<{\EndGobble}@{}}}
\only<4> {\newcolumntype{G}{|l}}
\begin{tabular}{G|l|l|l|}
\hline
\textbf{Mnemonic}& \textbf{\#} & \textbf{OSI} & \textbf{TCP/IP} \\ \hline
All & 7 & Application & \multirow{3}{*}{Application} \\ \cline{1-3}
People & 6 & Presentation & \\ \cline{1-3}
Seem & 5 & Session & \\ \hline
To & 4 & Transport & Transport \\ \hline
Need & 3 & Network & Internet \\ \hline
Data & 2 & Data Link & \multirow{2}{*}{Link Access} \\ \cline{1-3}
Processing & 1 & Physical & \\ \hline
\end{tabular}
\end{center}
\end{frame}
\end{document}
答案2
解决方法：在桌子上放置一个与背景颜色相同的矩形。
编辑：现在有相对覆盖说明 - 所以在表格前插入多少张幻灯片并不重要。
\documentclass[12pt]{beamer}
\usepackage{multirow} %Used for tables with merged cells
\usepackage{collcell} %pdflatex.exe hangs without this one
\usepackage{tikz}
\begin{document}
\begin{frame}{Communication Models}
\pause
\begin{tabular}{|l|l|l|l|}
\hline
\textbf{Mnemonic}& \textbf{\#} & \textbf{OSI} & \textbf{TCP/IP} \\ \hline
All & 7 & Application & \multirow{3}{*}{Application} \\ \cline{1-3}
People & 6 & Presentation & \\ \cline{1-3}
Seem & 5 & Session & \\ \hline
To & 4 & Transport & Transport \\ \hline
Need & 3 & Network & Internet \\ \hline
Data & 2 & Data Link & \multirow{2}{*}{Link Access} \\ \cline{1-3}
Processing & 1 & Physical & \\ \hline
\end{tabular}
\vspace*{-4.21cm}
\begin{tikzpicture}
\begin{onlyenv}<.(1)>
\draw [color=bg, fill=bg] (0,0) rectangle (2.42,4.2);
\end{onlyenv}
\end{tikzpicture}
\pause
\end{frame}
\end{document}
