My solution would be to change the block begin
template. It's default is defined in beamerinnerthemedefault.sty
as
\defbeamertemplate*{block begin}{default}
{
\par\vskip\medskipamount%
\begin{beamercolorbox}[colsep*=.75ex]{block title}
\usebeamerfont*{block title}\insertblocktitle%
\end{beamercolorbox}%
{\parskip0pt\par}%
\ifbeamercolorempty[bg]{block title}
{}
{\ifbeamercolorempty[bg]{block body}{}{\nointerlineskip\vskip-0.5pt}}%
\usebeamerfont{block body}%
\begin{beamercolorbox}[colsep*=.75ex,vmode]{block body}%
\ifbeamercolorempty[bg]{block body}{\vskip-.25ex}{\vskip-.75ex}\vbox{}%
}
In your document you can create an additional option for block begin
with has no title by deleting the first few lines of the definition:
%create template for block without title
\defbeamertemplate{block begin}{notitle}
{
\usebeamerfont{block body}%
\begin{beamercolorbox}[colsep*=.75ex,vmode]{block body}%
\ifbeamercolorempty[bg]{block body}{\vskip-.25ex}{\vskip-.75ex}\vbox{}%
}
Now you can turn off the title bar with \setbeamertemplate{block begin}[notitle]
and turn it back on with \setbeamertemplate{block begin}[default]
.
Of course this is only true if you use a inner theme
which uses \setbeamertemplate{block begin}[default]
. If your inner theme
uses another option for block begin
, you need to make a copy of that and change it accordingly. rounded
for example (used by inner theme
rounded
) is defined in beamerauxtemplates.sty
. Also the command to turn titles back on would need to be copied from your theme, in that case from beamerinnerthemerounded.sty
.
example
block puts "Example" in its title (had either of us actually compiled some code we would have seen it!). Incidentally, it is possible to change background colours in beamer. The manual has the details, and if that's not clear then ask a fresh question about it. – Andrew Stacey Aug 22 '11 at 13:20