# Customize beamer template to vary field for each slide?

I would like to use the lower left corner normally reserved for "author (institution)" (I am using the Boadilla template) to include additional text (like references/sources for figures) specific to that slide. Is this easy to customize? If so... how can I go about changing that for individual slides?

-

In the following example I defined a \MyText command which simply redefines de footline template by putting the argument in the field reserved for short author and institution. You have to use the command before the \begin{frame} command and use some grouping mechanism (\begingroup, \endgroup, for example) to keep the change local:

\documentclass{beamer}

\author{The author}
\institute{The Institute}
\title{The date}

\makeatletter
\newcommand\MyInfo[1]{%
\setbeamertemplate{footline}
{
\leavevmode%
\hbox{%
\end{beamercolorbox}%
\end{beamercolorbox}%
\end{beamercolorbox}}%
\vskip0pt%
}
}
\makeatother

\begin{document}

\begingroup
\MyInfo{Some text}
\begin{frame}
\frametitle{A frame with modified footline}
Test frame
\end{frame}
\endgroup

\begin{frame}
\frametitle{A frame with standard footline}
Test frame
\end{frame}

\begingroup
\MyInfo{Some other text}
\begin{frame}
\frametitle{Another frame with modified footline}
Test frame
\end{frame}
\endgroup

\end{document}

-
Wow, thank you!!! Works perfectly. This is fantastic. And new macros to digest... –  crippledlambda Oct 31 '11 at 1:41
@crippledlambda: You're welcome. I forgot to mention; the original definition of the footline beamer template used by the infolines outer theme (which is the outer theme used by Boadilla) can be found in the file beamerouterthemeinfolines.sty. –  Gonzalo Medina Oct 31 '11 at 1:50
Thanks! So footline is called by beamerouterthemeinfolines... I was looking at beamerthemeBoadilla.sty and was disappointed to see the original not defined there so this is good to know. Using this, I was also able to include \insertsectionhead in place of the \insertshorttitle which is also a useful modification... –  crippledlambda Oct 31 '11 at 2:05