Line number during cross-referencing. No Line number appears

Question

I read these two questions: 1 and 2, but I am still in a trouble.

So, I have two files:

test1.tex:

\documentclass[12pt,a4paper]{article}
\usepackage[nopar]{lipsum} 
\usepackage[pagewise]{lineno}
\begin{document}
    \linenumbers  % enable line numbering
    \lipsum[1-6]
    \\ \\
    \label{important}IMPORTANT INFORMATION
    \\ \\
    \lipsum[1-6]
\end{document}

and test2.tex:

\documentclass[12pt,a4paper]{article}
\usepackage[nopar]{lipsum} 
\usepackage{xr}
\externaldocument{test1}
\begin{document}
    Important information was given on line \ref{important} of page~\pageref{important}.
\end{document}

But line number did not appear. Could you help me to have referencing with line number?

Answer 1

You can refer with \ref to the number of a line, which has been marked with \linelabel{lne:item}. The command \lineref does something completely different, see the manual.

So you get your reference with:

\documentclass[12pt,a4paper]{article}
\usepackage[nopar]{lipsum} 
\usepackage[pagewise]{lineno}
\begin{document}
    \linenumbers  % enable line numbering
    \lipsum[1-6]

    \linelabel{lne:important}IMPORTANT INFORMATION

    \lipsum[1-6]

    The IMPORTANT INFORMATION ist given in line no. \ref{lne:important} on page
    \pageref{lne:important}

\end{document}

The result ist something like »The IMPORTANT INFORMATION ist given in line no. 12 on page 2« in the PDF.