LaTeX beamer fixed vertical alignment
I believe this is a better solution, which makes sure that the text, under the picture, will be kept in place.
\begin{frame}{Test}
\begin{center}
\includegraphics[width=0.8\linewidth]{bird.jpg}
\end{center}
\begin{center}
\begin{overprint}
\onslide<1>
Text for the first slide.\\
Maybe few lines\\
long...
\onslide<2>
Replacement on the second slide.\\
This time only two lines.
\end{overprint}
\end{center}
\end{frame}
If the text is below the image, this shouldn't be to much of a problem.
\begin{frame}
\begin{center}
\includegraphics{foo.pdf}
\end{center}
\uncover<+>{text on first slide}%
\uncover<+>{text on second slide}%
\uncover<+>{text on third slide}
\end{frame}
What's more challenging is a situation where the static material is below the dynamic material. Then you have to put the dynamic material in a box that is the same size on each slide. The most common ways to do that are with the overlay
and overprint
environments (see the beamer manual).
You can use [t]
specifier for the frame to be top-aligned, then the height of the contents below the picutre does not matter:
\documentclass{beamer}
\begin{document}
\begin{frame}[t]\frametitle{My Frame}
\begin{center}
\rule{3cm}{3cm} % substitute for a picture
\end{center}
\begin{itemize}
\only<1>{
\item First point on first slide
\item Second point on first slide
}
\only<2>{
\item Only one point on second slide
}
\end{itemize}
\end{frame}
\end{document}