I have seen Table with 100 % width and vertical / horizontal alignment, Vertically center text in tabularx table, Vertical alignment in tabularx X column type - and I'm trying what they suggest, but it doesn't work.
Consider this MWE:
\documentclass{article}
\usepackage{array,booktabs}
\usepackage{tabularx}
\usepackage{ragged2e}
\usepackage{hhline}
\newcolumntype{x}[1]
{>{\raggedright}p{#1}}
\newcolumntype{z}[1]
{>{\centering}p{#1}}
\newcommand{\tn}{\tabularnewline}
\renewcommand\tabularxcolumn[1]{>{\Centering}m{#1}} %% COMMENT
\begin{document}
\begin{table}[!h]%t1
\caption{A rather long explanation of what this table is supposed to be}
\small%
{%
\begin{tabularx}{\textwidth}%
{|x{2.6cm}|X|} %% COMMENT
% {|x{2.6cm}|>{\centering}X|} %% UNCOMMENT
\hline
Something something & something else \tn
\hhline{|=|=|}
\textbf{Item one} \\ {\small\it item ref 1} &%
param 01 / param 02 \\/ param3\tn
\hline
\textbf{Item two} \\ {\small\it item ref 2} &%
param 03 / param 04 \\/ param5\tn
\hline
\textbf{Item two} \\ {\small\it item ref 2} &%
param 03 / param 04 / param5\tn
\hline
\end{tabularx}}
\label{tab:sometable}
\end{table}
\end{document}
As is, this produces:
... so clearly something is broken (the \\
are seen as new table lines, I guess)?
But if you uncomment/comment the lines as marked with %%
in the MWE, it compiles almost fine:
... except there is no vertical centering - as evidenced by the 3rd row, 2nd column.
So how can I have a column that stretches, that allows line breaking inside a cell - and centers the text vertically?