![Beamer 标题带框架标题](https://linux22.com/image/308515/Beamer%20%E6%A0%87%E9%A2%98%E5%B8%A6%E6%A1%86%E6%9E%B6%E6%A0%87%E9%A2%98%20.png)
让我们考虑一下这个 MWE
\documentclass{beamer}
\makeatletter
\setbeamertemplate{frametitle}{}
\setbeamertemplate{headline}
{
\leavevmode
\begin{beamercolorbox}[wd=\paperwidth,ht=4.8ex,dp=2ex,left]{section in head}
\hspace{1ex}{\insertsection} -- {\insertframetitle}
\end{beamercolorbox}
}
\makeatother
\begin{document}
\section{Introduction}
\begin{frame}
\frametitle{One}
Hello
\end{frame}
\begin{frame}
\frametitle{Two}
World
\end{frame}
\end{document}
排版这个,错误
! Undefined control sequence.
\beamer@@tmpl@headline ...} -- {\insertframetitle
} \end {beamercolorbox}
l.14 \begin{document}
?
有解决办法吗?