Problem with counters

Question

I want to make a presentation with certain tasks, but since there are certain problems with using enumitem with beamer, I decided to make it myself, so I have this example code:

\documentclass{beamer}

\usepackage[english]{babel}
\usepackage[utf8]{inputenc}
\usepackage{ifthen}

\usetheme{CambridgeUS}

\newcounter{tasknumber}
\stepcounter{tasknumber}
\newcounter{taskletter}

\resetcounteronoverlays{tasknumber}
\resetcounteronoverlays{taskletter}

\newcommand{\task}[1][ ]
{
        \ifthenelse{\equal{#1}{+}}{
        \stepcounter{tasknumber}\setcounter{taskletter}{0}}{} %<- why this doesn't work?
        Task \thetasknumber.
}

\newcommand{\taskl}
{
    \stepcounter{taskletter}
    \alph{taskletter})
}

\begin{document}
    \begin{frame}
        \frametitle{\task}
        \taskl ...
        \taskl ...
        \taskl ...
    \end{frame}
    %\setcounter{taskletter}{0}
    \begin{frame}
        \frametitle{\task[+]}
        \taskl ...
        \taskl ...
        \taskl ...
    \end{frame}
\end{document}

Obviously, I want to get first frame for first task with a), b) and c), and second frame for second task with a) b) and c) as well, but I get d), e) and f) on second frame. I wouldn't like adding \setcounter{taskletter}{0} after every frame.

Answer 1

You should put \frametitle inside \task instead of the reverse.

\documentclass{beamer}

\usepackage[english]{babel}
\usepackage[utf8]{inputenc}
\usepackage{ifthen}

\usetheme{CambridgeUS}

\newcounter{tasknumber}
\stepcounter{tasknumber}
\newcounter{taskletter}

\resetcounteronoverlays{tasknumber}
\resetcounteronoverlays{taskletter}

\newcommand{\task}[1][ ]
{
        \ifthenelse{\equal{#1}{+}}{
        \stepcounter{tasknumber}\setcounter{taskletter}{0}}{} %<- why this doesn't work?
        \frametitle{Task \thetasknumber.}
}

\newcommand{\taskl}
{
    \stepcounter{taskletter}
    \alph{taskletter})
}

\begin{document}
    \begin{frame}
        \task
        \taskl ...
        \taskl ...
        \taskl ...
    \end{frame}
    %\setcounter{taskletter}{0}
    \begin{frame}
        \task[+]
        \taskl ...
        \taskl ...
        \taskl ...
    \end{frame}
\end{document}