beamer change color current bullet

Question

How do I change the color (to say red from blue) of bullet when that particular bullet is selected? Then when I move to the next bullet, bullet 2, bullet changes to red and bullet 1 is back to blue. I tried using alert but not working, I do not want to change the color nor background of the sentence, just the bullet's item color. Thank you Either change of color or moving from empty to solid

Answer 1

Use alert and let beamer do the work for you:

\documentclass{beamer}

\begin{document}
\begin{frame}
  \frametitle{Test}
  \begin{itemize}[<alert@+>\color{black}]
  \item First
  \item Second
  \item Third
  \end{itemize}
\end{frame}
\end{document}

Answer 2

With some help from beamer: change individual bullet color in itemize list,

\documentclass{beamer}
\newenvironment{Markenv}{\only{\setbeamercolor{local structure}{fg=red}}}{}
\begin{document}
\begin{frame}
  \frametitle{Test}
  \begin{itemize}
  \item<Mark@1> First
  \item<Mark@2> Second
  \item<Mark@3> Third
  \end{itemize}
\end{frame}
\end{document}