Missing footer on first Beamer slide of TikZ example

Question

I'm having problems with this particular TikZ example:

http://www.texample.net/tikz/examples/prims-algorithm/

When I change the theme, for instance:

\usetheme{Madrid}

the footer is not working on the first slide, but it is on the rest of them. Any idea how to solve this particular problem?

Answer 1

I don't know why, but the \pause command seems to be causing troubles. If you replace

\begin{pgfonlayer}{background}
    \pause
    \foreach \source / \dest in {d/a,d/f,a/b,b/e,e/c,e/g}
        \path<+->[selected edge] (\source.center) -- (\dest.center);
    \foreach \source / \dest / \fr in {d/b/4,d/e/5,e/f/5,b/c/6,f/g/7}
        \path<\fr->[ignored edge] (\source.center) -- (\dest.center);
\end{pgfonlayer}

by

\begin{pgfonlayer}{background}
    \foreach \source / \dest / \fr in {d/a/2,d/f/3,a/b/4,b/e/5,e/c/6,e/g/7}
        \path<\fr->[selected edge] (\source.center) -- (\dest.center);
    \foreach \source / \dest / \fr in {d/b/4,d/e/5,e/f/5,b/c/6,f/g/7}
        \path<\fr->[ignored edge] (\source.center) -- (\dest.center);
\end{pgfonlayer}

it works.