# Paragraph above scrolling enumerate in beamer keeping position

I have done this before using tricks with absolute positioning of nodes in tikz, or more crude by repeating the content manually in slides and using \phantom. I would like to know if there is a nice way to do the following:

I have a paragraph with an enumerate underneath.

Blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah,
blah, blah, blah, blah, blah.
1 Blah
2 Bleh
3 Blih


such that in the first slide it should appear as

Blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah,
blah, blah, blah, blah, blah.
1 Blah
2 Bleh


and in the next slide as

Blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah,
blah, blah, blah, blah, blah.
3 Blih


With the paragraph not changing position, as if the enumerate is scrolling.

Is there a nice way to do this? Nice meaning using some of those instructions already in beamer like \onslide, \only, \item<2->, or similar.

Another option to avoid the "jumping" effect is simply to use an overlayarea environment which was designed specifically for these cases. Adjust the width and height according to your needs:

\documentclass{beamer}

\begin{document}

\begin{frame}
\begin{overlayarea}{\linewidth}{4cm}
Some test text for the example test text for the example test text for the example test text for the example test text for the example
\begin{enumerate}
\only<1>{
\item First.
\item Second.}
\only<2>{\item[3.] Third.}
\end{enumerate}
\end{overlayarea}
\end{frame}

\end{document}


The result:

Here a solution:

\documentclass{beamer}

\begin{document}
\begin{frame}

Blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah,
blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah,
blah, blah, blah,
\begin{enumerate}

\only<1>{%
\item Blah
\item Blah
}

\only<2>{%
\item[3.] Blah
\item[]
}
\end{enumerate}

\end{frame}
\end{document}


which produce

• Are you sure it produces the effect? I haven't tried yet, but from reading the code I wonder what happens when the items are not necessarily one line and have different heights. – Anna Taurogenireva Jul 30 '15 at 21:31
• I updated my answer with an image of the output. – Salim Bou Jul 30 '15 at 22:12
• @MlazhinkaShungGronzalezLeWy it works in some cases, but will fail, for exmaple, if the text for the second \item spans more than one line, as in \only<1>{ \item Blah \item Blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, blah, } – Gonzalo Medina Jul 30 '15 at 22:18