beamer utility?

Question

Hello!

I want to make a presentation in Beamer. I have use Beamer for some time, still for this new feature I want to make in the presentation, I cannot find the solution with Beamer, as much as I would look for it. I hope that maybe you can help me with some idea. What I would want to do is the following: I want to have a slide with several text on it, and then on the next slide I would want to keep the same content, but over this content I would want to have a smaller slide on which I could add some text. The new text would be written on the old text. It is like when I have a slide with some text on it, I would want to make some remarks concerning this text, but these remark I want to put them on the old text. Do you think it is possible? any idea on how to do this?

Thank you very much for your time and suggestions, Madalina

Answer 1

It's hard to tell exactly what you're asking for. Beamer has a number of ways to implement "overlays". Take a look at this Beamer presentation and see if it's doing what you're thinking of: http://heather.cs.ucdavis.edu/~matloff/BeamerTour.pdf

IF it is, you can find the code here: http://heather.cs.ucdavis.edu/~matloff/beamer.html#tour

The example above, I believe, uses, the 'pause' and 'uncover' commands to do overlays. You can also specify uncovering using the itemize structure. In example below, the three items will be automatically revealed on subsequent frames:

\begin{itemize}
    \item<1->One good argument
    \item<2->Another good argument, after one click
    \item<3->Last one, after another click
\end{itemize}

Answer 2

If I understand you correctly, you would like to do things like add arrows (or textbubbles) next to existing content. You could combine beamer with tikz overlays to accomplish this.

You can the use a command like \tikz[remember picture] \node[coordinate] (p1) {}; to indicate a position that you want to highlight. Later you can reference this position (p1) from a tikz environment where you specify the overlay parameter. Search for /tikz/overlay in the pgfmanual for further information (and consult the rest of the manual for how to use tikz).

\documentclass{beamer}
\usepackage{tikz}
\usetikzlibrary{calc} 
\begin{document}

\begin{frame}{Test}

\begin{itemize}
  \item First item.
  \item Second\tikz[remember picture] \node[coordinate] (p1) {}; item. 
  \item Third item.
\end{itemize}

\begin{uncoverenv}<2>
\begin{tikzpicture}[remember picture,overlay] 
  \node[rounded corners=4pt,fill=red] (p2) at ($(p1) + (1cm,-2mm)$) {Nice};
  \draw[<-,very thick] (p1.west) -- (p2);
\end{tikzpicture} 
\end{uncoverenv}

\end{frame}

\end{document}

Note that you need to generate the document twice for the tikz overlays to get to the right position.