[Tex/LaTex] Accessing the current frame number in beamer

beamercounters

I know how to manually reset the page counter using a fix value. In the MWE below this fix value 0. Now I wonder how to use a variable value like \framenumber - 1. In this question it was asked for the counter of the overlay with the solution \overlaynumber; but \framenumber is an "unidentified controll sequence". Reading this question I experimented with \beamer@slideinframe and \arabic{slideinframe} finding, that the latter will always give the same number, and does not increases when called later in the document.

\documentclass{beamer}
\usetheme{metropolis}

\begin{document}
\begin{frame}{Counter should be 1}
\end{frame}
\setcounter{framenumber}{0}
\begin{frame}{Counter should again be 1}
\end{frame}
\begin{frame}{Counter should be 2}
\end{frame}
\setcounter{framenumber}{1}
\begin{frame}{Counter should again be 2}
\end{frame}
\end{document}

Best Answer

3 different possibilities how not to increase the frame counter from one page to the next:

Excluding a frame from contributing to the frame counter

\documentclass{beamer}
\usetheme{metropolis}

\begin{document}
\begin{frame}{Counter should be 1}
\end{frame}

\begin{frame}[noframenumbering]{Counter should again be 1}
\end{frame}

\begin{frame}{Counter should be 2}
\end{frame}

\begin{frame}[noframenumbering]{Counter should again be 2}
\end{frame}

\end{document}

Manually adjusting the frame counter

\documentclass{beamer}
\usetheme{metropolis}

\begin{document}
\begin{frame}{Counter should be 1}
\end{frame}

\addtocounter{framenumber}{-1}
\begin{frame}{Counter should again be 1}
\end{frame}

\begin{frame}{Counter should be 2}
\end{frame}

\addtocounter{framenumber}{-1}
\begin{frame}{Counter should again be 2}
\end{frame}

\end{document}

Not using different frames

\documentclass{beamer}
\usetheme{metropolis}

\begin{document}

\begin{frame}
\frametitle<1>{Counter should be 1}
\frametitle<2>{Counter should again be 1}
\only<1>{slide 1}
\only<2>{slide 2}
\end{frame}

\begin{frame}
\frametitle<1>{Counter should be 2}
\frametitle<2>{Counter should again be 2}
\only<1>{slide 1}
\only<2>{slide 2}
\end{frame}


\end{document}