Using tikz to strike out a beamer block

Question

In this post I found this command to strike out words with a red cross:

\newcommand\mycrossed[1]{\tikz[baseline=(A.base)]
    \node[cross out, draw= red, draw opacity=0.5, line width=1.5pt,
          inner sep=0pt, outer sep=0pt] (A) {#1};%
                        }

Anyway, if the argument of the post is a beamer block, the command does not work. I tried to include the block in a minipage without success. How I can obtain a similar effect with entire blocks?

score 1 · Accepted Answer · answered Jan 18 '21 at 21:58

The code below is modified from https://tex.stackexchange.com/a/96304/. It shows a block in a minipage in a tikzpicture. The tikzpicture defines coordinates (north east, south west etc.) that can be used to draw a cross.

The anchors are a bit off at the top (the north anchor is higher than the upper part of the block), so you can lower those coordinates with the calc tikzlibrary and the ($(coord1)+(coord2)$) syntax.

Finally a new command is defined to add other blocks easily without needing to add the tikzpicture manually every time.

\documentclass{beamer}
\usepackage{tikz}
\usetheme{Frankfurt}
\usetikzlibrary{calc}
\begin{document}
\newcommand{\crossblock}[2]{%
\begin{tikzpicture}
    \node (n1) {%
    \begin{minipage}{\textwidth}
    \begin{block}{#1}%
      #2
    \end{block}%
    \end{minipage}
    };
    \draw[red,ultra thick] (n1.south west) -- ($(n1.north east)-(0pt,10pt)$);
    \draw[red,ultra thick] ($(n1.north west)-(0pt,10pt)$) -- (n1.south east);
\end{tikzpicture}
}
\begin{frame}
\crossblock{Block title}{Block text\par another line\par third line}
\crossblock{Second title}{Second contents\par next line}
\end{frame}
\end{document}

Using tikz to strike out a beamer block

1 Answers1