[Tex/LaTex] Beamer: show subitem at the same time as the item

Question

In Beamer whenever you have

\begin{itemize}[<+->]
\item A
\begin{itemize}
\item a1
\item a2
\end{itemize}
\item B
\item C
\end{itemize}

subitem a1 appears after item A.

What if I want that when A appears the first subitem also appear?

Thank you

Answer 1

To let the first subitem appear, you have to tell it explicitly with:

\item<.>

or

\item<.->

which does not increase the overlay specification (the second makes persistent the item).

\documentclass{beamer}
\usepackage{lmodern}

\begin{document}
\begin{frame}
\begin{itemize}[<+->]
\item A
\begin{itemize}
\item<.-> a1
\item a2
\end{itemize}
\item B
\item C
\end{itemize}
\end{frame}
\end{document}