一张幻灯片内的计时命令

Question

命令 \transduration{time}\effect（例如 \transduration{10}\transfade）用于自动播放幻灯片和幻灯片中的元素。但似乎参数“时间”在一张幻灯片中必须是恒定的。是否可以为出现在一张幻灯片上的不同元素设置不同的时间？（例如，列表中的项目取决于它们的长度）？

例如，

\begin{frame}
\begin{enumerate} 
\item This is a long item. This is a long item. This is a long item. This is a   long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. \pause
\item This is a short item. This is a short item. \pause
\item This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. \pause
\item This is a short item. This is a short item. \pause

\end{enumerate}
\transduration{2}\transfade
\end{frame}

Answer 1

是的，这是可能的，但不是自动的。由于\transduration是覆盖感知的，你可以这样做

\transduration<1>{10}
\transduration<2>{2}
\transduration<3>{10}
\transduration<4>{2}

还要注意[<+->]覆盖规范，enumerate因此您不必手动引入\pause：

\documentclass{beamer}

\begin{document}

\begin{frame}
\begin{enumerate}[<+->]
\item This is a long item. This is a long item. This is a long item. This is a   long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item.
\item This is a short item. This is a short item.
\item This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item. This is a long item.
\item This is a short item. This is a short item.
\end{enumerate}
\transduration<1>{10}
\transduration<2>{2}
\transduration<3>{10}
\transduration<4>{2}
\transfade
\end{frame}

\end{document}