How to set up beamer to grey out past items but hide future items?

Question

I know about beamer's feature \setbeamercovered{invisible} and \setbeamercovered{transparent} to hide or grey out upcoming item's . But is there some way to have past items greyed (transparent) and future items hidden (invisible), so that only the current item is black/highlighted? And the best would be if on or 1 slide after the last all the item's could be visible highlighted. Something like this:

• [grey] past 1
• [grey] past 2
• current
• [hidden] future 1
• [hidden] future 2
• [hidden] future 3

Is there any easy way of doing this?

Answer 1

From the beamer manual, section 17.6 (Transparency Effects), use \setbeamercovered to set the default cover behavior, and override it for old items with the again covered option.

\documentclass{beamer}
\setbeamercovered{invisible}
\setbeamercovered{%
  again covered={\opaqueness<1->{15}}}
\begin{document}
\begin{frame}
\begin{itemize}[<+>]
\item Apple
\item Peach
\item Plum
\item Orange
\end{itemize}
\end{frame}
\end{document}