tree list in a table

Question

I would like to put a tree list into a table environment. Smth. like:

+--------------------------+---------------------------+-------------+
| Heading 1                |  Heading 2                | Heading 3   |
+--------------------------+---------------------------+-------------+
| / main-item              |  main item data           | some info   |
|   +-- sub item 1         |  sub item 1 data          | some info 1 |
|   |   +-- sub sub item x |  sub sub item 1.x data    | some info x |
|   |                      |                           |             |
|   +-- sub item 2         |  sub item 2 data          | some info 2 |
|       +-- sub sub item y |  sub sub item 2.y data    | some info y |
+--------------------------+---------------------------+-------------+

I know about dirtree package, but it it possible to arrange dirtree data in that way?

P.S.: I received multiple answers to this question, which solve the problem. I personally found the accepted answer more appropriate in my case. But here are also answers how to achieve the requested functionality with dirtree package. Therefore I encourage everyone to read all answers to find the best possible solution.

Answer 1

Here an example how you can mimic that with pure table environment. But you don't have connections between sub-items.

Hope that helps anyway.

\begin{table}[p]
\begin{center}
    \caption{Some caption of your table} \label{tab:trendtable}
    \begin{tabular}{lll}
    \midrule[1pt]
    \multicolumn{1}{c} {Heading 1} & multicolumn{1}{c} {Heading 2} & \multicolumn{1}{c} {Heading 3} \\ 
    \midrule[1pt]
    \textbf{main-item}             & main item data        & some info\\
    \hspace{0.2cm} sub item 1      & sub item 1 data       & some info 1 \\
    \hspace{0.4cm} sub sub item x  & sub item 1.x          & some info x \\
    &&\\
    \textbf{main-item 2}           & ...                   & ...\\
    \hspace{0.2cm} ...             & ...                   & ... \\
    \end{tabular}
\end{center}
\end{table} 

Answer 2

You can use dirtree within a table, just enclose the mark-up within a minipage and be careful with the stops at the end of the lines! Here is a minimal example:

\documentclass{article} 
\usepackage{dirtree}
\begin{document}
\begin{tabular}{|l|l|}
\begin{minipage}{4cm}\dirtree{%
.1 Engineering.
.2 Mechanical.
.3 Electrical.
.4 Electronics.
}\end{minipage}    
& \begin{minipage}{4cm}\dirtree{%
.1 TeX.
.2 LaTeX.
.3 XeTeX.
.4 pdfLaTeX.
}\end{minipage}\\
\end{tabular}
\end{document}

Edit as per comments

\begin{tabular}{|l|p{3cm}|}
\begin{minipage}[t]{4cm}\dirtree{%
.1 Engineering.
.2 Mechanical.
.3 Electrical.
.4 Electronics.
}\end{minipage}    
&  Director A  
   \newline Director B 
   \newline Director C
   \newline Director D\\
\end{tabular}

This will produce an output as requested (two columns) the third is trivial! For anything more fancy I would use a graphics package such as TikZ or pstricks. This sort of layout IMHo is better produced using, just minipages and or specially constructed environments. Nevertheless dirtree is a great package and one can use it for all sorts of different problems.

Answer 3

Here is a direct solution (based entirely off of Yiannis's answer) which solves the problem.

\documentclass{article} 
\usepackage{dirtree,array}
\setlength{\extrarowheight}{3pt}
\begin{document}
\begin{tabular}{|l|l|l|}
\hline
\multicolumn{1}{|c} {Heading 1} & \multicolumn{1}{|c|} {Heading 2} & \multicolumn{1}{c|}{Heading 3}\\
\hline
\begin{minipage}{4cm}\dirtree{%
.1 Engineering.
.2 Mechanical.
.3 Bio-mechanical.
.2 Electronics.
}\end{minipage}
&
\DTsetlength{0pt}{0pt}{0pt}{0pt}{0pt}
\begin{minipage}{6cm}\dirtree{%
.1 Stuff about engineering here.
.2 Stuff about Mechanical here.
.3 Stuff about biomechanical here.
.4 .
}\end{minipage}
&
\DTsetlength{0pt}{0pt}{0pt}{0pt}{0pt}
\begin{minipage}{4cm}\dirtree{%
.1 Comments.
.2 More comments.
.3 Still more.
.4 And more.
}\end{minipage}\\
\hline
\end{tabular}
\end{document}
&
\DTsetlength{0pt}{0pt}{0pt}{0pt}{0pt}
\begin{minipage}{6cm}\dirtree{%
.1 Stuff about engineering here.
.2 Stuff about Mechanical here.
.3 Stuff about Electrical here.
.4 .
}\end{minipage}
\end{tabular}
\end{document}