Hyperlinks from a TikZ tree

Question

I am trying to combine this answer on how to create hyperlinks with a tree hierarchy taken from the filesystem tree example. While the basic hyperlinking works, I get an error message as soon as I introduce the link style into the tree nodes. The error message is

! Package pgf Error: No shape named  is known.

How can I combine the two partial solutions? The example I use is

\documentclass{article}
\usepackage[hidelinks]{hyperref}
\usepackage{tikz}
\usetikzlibrary{trees,calc}
\begin{document}
\tikzset{
    hyperlink node/.style={
        alias=sourcenode,
        append after command={
            let     \p1 = (sourcenode.north west),
                \p2=(sourcenode.south east),
                \n1={\x2-\x1},
                \n2={\y1-\y2} in
            node [inner sep=0pt, outer sep=0pt,anchor=north west,at=(\p1)] {\hyperref[#1]{\phantom{\rule{\n1}{\n2}}}}
        }
    }
}

\tikzstyle{every node}=[draw=black,thick,anchor=west]

% simple drawing - works
\begin{tikzpicture}
  \node [draw, inner sep=2ex,hyperlink node=sec:foo] {Go to Page Two};
\end{tikzpicture}

% tree without link - works 
\begin{tikzpicture}[%
  grow via three points={one child at (0.5,-0.7) and
  two children at (0.5,-0.7) and (0.5,-1.4)},
  edge from parent path={([xshift=2ex]\tikzparentnode.south west) |- (\tikzchildnode.west)},
  growth parent anchor=west]
  \node {Root Beer Rag}
    child { node {Go to Page Two}};
\end{tikzpicture}

% tree with link - error
\begin{tikzpicture}[%
  grow via three points={one child at (0.5,-0.7) and
  two children at (0.5,-0.7) and (0.5,-1.4)},
  edge from parent path={([xshift=2ex]\tikzparentnode.south west) |- (\tikzchildnode.west)},
  growth parent anchor=west]
  \node [hyperlink node=sec:foo] {Root Beer Rag}
    child { node {Go to Page Two}};
\end{tikzpicture}

\clearpage
\section{Target} 
\label{sec:foo}

\end{document} 

Answer 1

After some tries I got option label to work, but I haven't found a nice way for getting the size of the node inside the label for \rule except for storing the positions via \pdfsavepos (needs two LaTeX runs). Finally I found something in the source code for option label. It adds a node, but avoids the problem by restoring \tikz@last@fig@name.

The example uses the default box annotations with red frame to show the annotation rectangle. I have used pdflatex with \pdflinkmargin=1pt as default. Thus the rectangle is a little bit larger:

\documentclass{article}
\usepackage{hyperref}
\usepackage{bookmark}
\usepackage{tikz}
\usetikzlibrary{trees,calc}

\begin{document}

\makeatletter
\tikzset{
  hyperlink node/.style={
    append after command={%
      \bgroup
        [current point is local=true]
        \pgfextra{%
          \let\tikz@save@last@fig@name=\tikz@last@fig@name
        }%
        let \p1=(\tikzlastnode.south west),
            \p2=(\tikzlastnode.north east),
            \n1={\x2-\x1},
            \n2={\y2-\y1}
        in
        node[
          at=(\p1),
          draw=none,
          shape=rectangle,
          inner sep=0pt,
          outer sep=0pt,
          minimum width=0pt,
          minimum height=0pt,
        ]{%
          \rlap{%
            \raisebox{0pt}[0pt][0pt]{%
              \hyperref[{#1}]{%
                \phantom{\rule{\n1}{\n2}}%
              }%
            }%
          }%
        }%
        \pgfextra{%
          \global\let\tikz@last@fig@name=\tikz@save@last@fig@name
        }%
      \egroup
    },
  },
}
\makeatother

\tikzstyle{every node}=[draw=black,thick,anchor=west]

\begin{tikzpicture}[%
  grow via three points={one child at (0.5,-0.7) and
  two children at (0.5,-0.7) and (0.5,-1.4)},
  edge from parent path={([xshift=2ex]\tikzparentnode.south west)
      |- (\tikzchildnode.west)},
  growth parent anchor=west]
  \node [hyperlink node=sec:foo] {Go to Target Foo}
    child { node {First Child}}
    child { node[hyperlink node=sec:bar] {Go to Target Bar}}
  ;
\end{tikzpicture}

\clearpage
\section{Target Foo} 
\label{sec:foo}

\clearpage
\section{Target Bar}
\label{sec:bar}
\end{document}