Highlight the next uncovered part in beamer

Question

I have created the code below to highlight the parts where something need to be completed by the students. It works, but

• instead of frames there should be a light colored background
• this background would appear just before the part will be uncovered to know where is the next problem to solve
• the beamerarticle form should not have the frames (background color is all right)

My code:

\documentclass{beamer}
\newcommand{\frameuncover}[2]{\framebox{\uncover<#1>{#2}}}

\begin{document}

\begin{frame}[fragile]
  {Hamming distance}

    The Hamming distance of the code below is \frameuncover{5-}{4}.

\begin{verbatim}
a 01010101
b 00001111
c 00110010
\end{verbatim}

d(ab) = \frameuncover{2-}{4}

d(bc) = \frameuncover{3-}{5}

d(ac) = \frameuncover{4-}{5}

\end{frame}

\end{document}

Answer 1

Edit: fixed the wiggle by using even more phantom and colorbox with the background color.

If I understand you right, this would do the trick, the first option would be for the appearance of the color box, the second for the color of the box and the last one the actual text.

There is a problem with showing the last slide hence the \only<5>{} just to show the final slide.

\documentclass{beamer}

\definecolor{custom}{rgb}{1,0.8,0.8}

\newcommand{\coloruncover}[3]{\temporal<#1>{\colorbox{bg}{\phantom{#3}}}{\colorbox{#2}{\phantom{#3}}}{\colorbox{bg}{#3}}}

\begin{document}

 \begin{frame}[fragile]
  {Hamming distance}

  The Hamming distance of the code below is \coloruncover{4}{custom}{4}\only<5>{}.

  \begin{verbatim}
   a 01010101
   b 00001111
   c 00110010
  \end{verbatim}

  d(ab) = \coloruncover{1}{custom}{4}   d(bc) = \coloruncover{2}{custom}{5}  d(ac) = \coloruncover{3}{custom}{5}

\end{frame}

\end{document}