LaTeX beamer fixed vertical alignment

Question

I am building a presentation in Beamer.

The presentation contains a slide where an image should be displayed on the top of the frame. Underneath some text should be displayed containing information about the image. The text should change frame by frame (other information, no overlays). Therefore the image needs to stay on it's initial place of course.

Are there any ways to do this, or is there some workaround (elegant solution)?

Answer 1

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}

Answer 2

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).

Answer 3

You could also use the overlayarea. Consider the following MWE:

\documentclass{beamer}

\usepackage{tikz}

\begin{document}
\begin{frame}
  \frametitle{TBA}
  \begin{overlayarea}{\textwidth}{2cm}
    \begin{center}
      \begin{tikzpicture}
        \draw (-1,-1) -- (1,1);
      \end{tikzpicture}
    \end{center}
  \end{overlayarea}
  \begin{overlayarea}{\textwidth}{2cm}
    \only<1>{Bla}
    \only<2>{Blo}
  \end{overlayarea}
\end{frame}
\end{document}

Note that this option, namely using overlayarea let the user have a great degree of freedom. For example, in combination with minipage, one can achieve similar effect only with two "vertical columns".

Answer 4

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}