Trying to hide blocks of text in beamer
Here's a way of defining a \hideit
using Beamer's extended \newcommand
:
\documentclass[handout]{beamer}
\setbeamercolor{math text}{fg=blue}
\newcommand\hideit[1]{%
\only<0| handout:1>{\mbox{}}%
\invisible<0| handout:1>{#1}}
\begin{document}
\begin{frame}
\frametitle{Two bugs:}
{\color{red}Error with itemize}
\begin{itemize}
\item The line below should have a `bullet' (only the
text should be hidden)
\item \hideit{Some text to be hidden}
\item This is visible again.
\end{itemize}
\bigskip
{\color{red}Error with beamer's pause command:}
\textbf{Example 1:}\quad Differentiate \ $f(x)=x^2\sin x$
\bigskip
\underline{\itshape Solution:}
\hideit{Let $u=x^2$ and $v=\sin x$. (this line should be hidden)
\pause Then $u'=2x$ and $v'=\cos x$.
Using the product rule we get
$$f' = 2x\sin x + x^2\cos x.$$
}
\end{frame}
%%%%%%%%%%%
\begin{frame}
\frametitle{Two more bugs:}
{\color{red}Error with `inline' hiding:}
Here is some \hideit{hidden} text on one line.
\bigskip
{\color{red}Error with eqnarray* in beamer:}
\textbf{Example 1:}\quad Differentiate \ $f(x)= \frac{\sin x}{e^x}$.
\medskip
\underline{Solution:} Let $u=\sin x$ and $v=e^x$.
Then $u'=\cos x$ and $v'=e^x$. Therefore
\hideit{\begin{eqnarray*}
f'(x) &=& \frac{e^x\cos x-(\sin x)e^x}{(e^x)^2} \\
&=& \frac{e^x(\cos x-\sin x)}{(e^x)^2} \\
&=& \frac{\cos x-\sin x}{e^x}.
\end{eqnarray*}
}
And that's how you do it! (This should be black text)
\end{frame}
\end{document}
And for the presentation:
I shortened the example to show the relevant feature with \mode<handout>{...}
and \mode<beamer>{...}
, which is basically beamer
's own way of \hideit
etc.
\documentclass[handout]{beamer}
\setbeamercolor{math text}{fg=blue}
%%%%
\begin{document}
%%%%%%%%%%%
\begin{frame}{Two bugs:}
%\frametitle{Two bugs:}
%{\color{red}Error with itemize}
\begin{itemize}
\item The line below should have a `bullet' (only the text should be hidden)
\mode<handout>{%
\item
}%
\mode<beamer>{%
\item Some text to be hidden
}%
\item This is visible again.
\end{itemize}
\end{frame}
%%%%%%%%%%%
\end{document}
Beamer mode
Handout mode