texttt、textsc 和 textmd 与 beamer slides 不兼容

Question

我尝试了beamer幻灯片语法中的\texttt、\textsc和\textmd命令，但不起作用。它对其他命令有效。我发现在第二张幻灯片上显示打字机文本的唯一方法是\only<2>{\ttfamily}。

\documentclass{beamer}

\begin{document}
\begin{frame}
    %These work
    \textbf<2>{Bold in the second slide}\\
    \textit<2>{Italic in the second slide}\\
    \textsf<2>{Sans-serif in the second slide}\\
    \textsl<2>{Slanted in the second slide}\\
    \emph<2>{Emphasized in the second slide}\\
    %These don't
    \textrm<2>{Roman in the second slide}\\
    \textsc<2>{Small caps in the second slide}\\
    \texttt<2>{Typewriter in the second slide}\\
    \textmd<2>{Medium-weight in the second slide}
\end{frame}
\end{document}

为什么这三个命令对幻灯片不起作用？

Answer 1

、\textmd和均未定义覆盖规范（不要问为什么，很可能\textsc是因为至少和在演示中看起来不太好看，但这仅是猜测！）\textttbeamer\texttt\textsc

\textsc根本无法与给定的字体一起使用，因此我lmodern另外使用了。

系统提供了使用覆盖规范beamer的复杂版本（参见示例）。请注意，最后一个参数数字实际上是用于覆盖的。\newcommand\renewcommand

\documentclass{beamer}
\let\textmdorig\textmd
\let\textscorig\textsc
\let\textttorig\texttt

\usepackage{lmodern}
\usepackage[T1]{fontenc}
\begin{document}


\renewcommand<>{\textmd}[1]{%
  \only#2{\textmdorig{#1}}%
}
\renewcommand<>{\textsc}[1]{%
  \only#2{\textscorig{#1}}%
}
\renewcommand<>{\texttt}[1]{%
  \only#2{\textttorig{#1}}%
}


\begin{frame}
    %These work
    \textbf<2>{Bold in the second slide}

    \textit<2>{Italic in the second slide}

    \textsf<2>{Sans-serif in the second slide}

    \textsl<2>{Slanted in the second slide}

    \emph<2>{Emphasized in the second slide}

    \textrm<2>{Roman in the second slide}

    \textsc<2>{Small Caps In The Second Slide}

    \texttt<2>{Typewriter in the second slide}

    \textmd<2>{Medium-weight in the second slide}
\end{frame}
\end{document}