in longtable a Bold \cline and colored column

Question

I have a longtable with some thick horizontal lines (I know and agree, lines are ugly, but I have to do it). Works good with package boldline and \clineB. But it interferes with colored Columns.

Am I able to fix this?

The example is completely stripped, in realiter it is much more complex, with some codechange in \LT@output for footer and header value-overflows

\documentclass[12pt]{article}
\usepackage{longtable}
\usepackage[table]{xcolor}
\usepackage{boldline}
\definecolor{Gray}{gray}{0.85}
\newcolumntype{g}{>{\columncolor{Gray}}r}
\newcolumntype{G}[1]{>{\columncolor{Gray}}p{#1}}
\begin{document}
\begin{longtable}{@{}|p{2cm}|G{3cm}|c|}\hline
Ueb1 & Ueb2 & Ueb3\\\hline
Zeile1 & Inhalt & Inhalt\\\hline
Zeile2 & Inhalt & Inhalt\\\clineB{1-1}{4}\clineB{2-2}{6}\clineB{3-3}{4}
Zeile3 & Inhalt & Inhalt\\\hline
\end{longtable}
\end{document}

i have seen this (https://golatex.de/problem-mit-cline-und-hintergrundfarbe-von-spalten-t12684.html), but I could get the soulutions to work with my setup.

Answer 1

Boldline, and the bold lines from makecell have problems with colour in tables. For lines of variable widths, you can load booktabs and neutralise locally the padding added around the rules, or use the \specialrule command, which lets you set the width, padding above and padding below:

\documentclass[12pt]{article}
\usepackage{longtable}
\usepackage[table]{xcolor}
\usepackage{booktabs}
\usepackage{boldline}
\definecolor{Gray}{gray}{0.85}
\newcolumntype{g}{>{\columncolor{Gray}}r}

\begin{document}

\begin{longtable}{@{}|c|g|c|}\hline
Ueb1 & Ueb2 & Ueb3\\\hline
Zeile1 & Inhalt & Inhalt\\\hline
Zeile2 & Inhalt & Inhalt\\
\specialrule{1.6pt}{0pt}{0pt}%
Zeile3 & Inhalt & Inhalt\\\hline
\end{longtable}

\end{document} 

In case you want a horizontal rule to have a varying width (depending on the column), it's easy to obtain with booktabs \cmidrules, but this will result in gaps in the vertical rules. So I suggest a plain \hline with a series of convenient \hhlines above and below, like this code

\begin{longtable}{@{}|p{2cm}|G{3cm}|c|}
\hline
Ueb1 & Ueb2 & Ueb3\\\hline
Zeile1 & Inhalt & Inhalt\\\hline
Zeile2 & Inhalt & Inhalt\\
\hhline{|~|-|~|}
\hhline{|~|-|~|}
\hline
\hhline{|~|-|~|}
\hhline{|~|-|~|}
Zeile3& Inhalt & Inhalt \\
\hline
\end{longtable}