%% 
%%  Ein DANTE-Edition Beispiel
%% 
%%  Beispiel 04-25-4 auf Seite 143.
%% 
%%  Copyright (C) 2010 Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 

% Show page(s) 1

\PassOptionsToClass{}{beamer}
\documentclass{beamer}
\usepackage[utf8]{inputenc}


\newcounter{definition}[section]
\resetcounteronoverlays{definition}
\makeatletter
\setbeamertemplate{theorem begin}{% depends on theorem
  \refstepcounter{definition}%
  \begin{\inserttheoremblockenv}{\inserttheoremname~\thesection.\thedefinition
    \ifx\inserttheoremaddition\@empty\else\ (\inserttheoremaddition)\fi}}
\makeatother


\begin{document}
\section{foo} \Large
\begin{frame}{Nummerierte Theorem- und Definitionsumgebungen}
\begin{definition} foo bar baz \end{definition}
\begin{theorem}    foo bar baz \end{theorem}
\begin{proof}    foo bar baz \end{proof}
\begin{example}    foo bar baz \end{example}
\end{frame}
\end{document}