In most documents, you can do this, which avoids the use of extra packages.
\let\tempone\itemize
\let\temptwo\enditemize
\renewenvironment{itemize}{\tempone\addtolength{\itemsep}{0.5\baselineskip}}{\temptwo}
(Stufazi suggested a neater way of doing this in his answer, which I will use below.)
However, I think that the frame
environment in beamer
resets the properties of itemize
. You could do something like this, but it will prevent frame
's optional arguments from working.
\documentclass{beamer}
\let\oldframe\frame
\renewcommand{\frame}{%
\oldframe
\let\olditemize\itemize
\renewcommand\itemize{\olditemize\addtolength{\itemsep}{100pt}}%
}
%
\begin{document}
\begin{frame}
\begin{itemize}
\item The first.
\item The second.
\item The third.
\end{itemize}
\end{frame}
%
\begin{frame}
\begin{itemize}
\item The fourth.
\item The fifth.
\item The sixth.
\end{itemize}
\end{frame}
%
\end{document}
Alternatively, you could try this, but I can't guarantee that it won't break something else.
\documentclass{beamer}
\newlength{\wideitemsep}
\setlength{\wideitemsep}{\itemsep}
\addtolength{\wideitemsep}{100pt}
\let\olditem\item
\renewcommand{\item}{\setlength{\itemsep}{\wideitemsep}\olditem}
%
\begin{document}
\begin{frame}
\begin{itemize}
\item The first.
\item<2-> The second.
\item<3-> The third.
\end{itemize}
\end{frame}
%
\begin{frame}[shrink=50]
\begin{itemize}
\item The fourth.
\item The fifth.
\item The sixth.
\end{itemize}
\end{frame}
%
\end{document}
It might be safer to define your own list environment based on itemize and use this in future; thus
\newenvironment{wideitemize}{\itemize\addtolength{\itemsep}{100pt}}{\enditemize}
This would avoid the necessity for hacks that have unwanted side effects.
There are two things going on in this situation. For those who know about LaTeX's list parameters, there is a \topsep
being added before the itemize list. The other is
that this item is starting in vertical mode, so a \partopsep
is also being added.
We thus need to do two things in this situation: (1) set \topsep
to zero for the list, via a redefinition \@listi
, and (2) clear \partopsep
.
The best way to do this is to add this to block begin
template. Here is an example, based on the essentials of your code.
\documentclass[10pt]{beamer}
\usepackage{lmodern}
\usepackage[T1]{fontenc}
\usetheme{default}
\usecolortheme{crane}
\setbeamertemplate{itemize items}[square]
\setbeamercolor{item}{fg=black}
\setbeamercolor{frametitle}{fg=black}
\setbeamercolor{block title}{fg=black}
\setbeamercolor{title}{fg=black}
\setbeamercolor{block body}{bg=white}
\makeatletter
\addtobeamertemplate{block begin}{
\def\@listi{\leftmargin\leftmargini
\topsep 0pt
\parsep 0pt
\itemsep 3pt plus 2pt minus 3pt}
\partopsep 0pt
}
\makeatother
\begin{document}
\begin{frame}
\frametitle{text vs. item blocks}
\begin{columns}[t]
\begin{column}{0.42\textwidth}
\begin{block}{text block}
block block block block block\vadjust{\hrule}
block block block block block
block block block block block
block block block block block
\end{block}
\end{column}
\begin{column}{0.48\textwidth}
\begin{block}{item block}
\begin{itemize}
\item item\vadjust{\hrule}
\item item
\item item
\end{itemize}
\end{block}
\end{column}
\end{columns}
\end{frame}
\end{document}
I have placed the blocks side-by-side and added the \vadjust{\hrule}
for illustration purposes. The values for \@listi
are based on beamers defaults which are
\def\@listi{\leftmargin\leftmargini
\topsep 3\p@ \@plus2\p@ \@minus2.5\p@
\parsep 0\p@
\itemsep3\p@ \@plus2\p@ \@minus3\p@}
\partopsep
has default value
2.0pt plus 1.0pt minus 1.0pt
If you want the individual lines to match up, then you should also put \itemsep
equal to 0pt
in the above code.
Beaware that if the titles of the two blocks have different heights/depths then theh body will move accordingly and you will loose your alignment again. You can cover yourself a little by adding an appropriate strut to your block titles.
Note that the above code also kills \topsep
for subsquent uses of itemize
within the same block. If this is a problem, you might try to just adjust \partopsep
to cancel out \topsep
and ensure that your subsequent lists in the block do not start in vertical mode.
Best Answer
This issue appears to be solved by leaving a blank line before the nested itemize: