How to fix diferent position of the line (space between the line and a page number and paragraphs) in the header using \pagestyle{uheadings}

Question

I have noticed that in the document I am working on the line in the header is changing position page to page. Basically there are two slightly (but notably) different vertical spaces between the line and the page number.

I managed to find out that the line's position is different using \doublespacing and \singlespacing.

Here is MWE: (need to be run twice - with \doublespacing and \singlespacing to see the difference of the line position)

\documentclass[12pt,a4paper,oneside]{mwbk}
\usepackage{enumitem}
\usepackage[cp1250]{inputenc}
\fussy
\addtolength{\textwidth}{1,5cm}
\addtolength{\hoffset}{0cm}
\addtolength{\textheight}{0cm}
\addtolength{\voffset}{0cm}

\usepackage{setspace}
\pagestyle{uheadings}

\usepackage{lipsum}

\begin{document}

\doublespacing         %different position when using \singlespacing
%\singlespacing

\lipsum[1-10] 

\end{document}

Have you any idea how I can fix the position of the line while I am using different spacing in the document and the line has different position depending on what is in the code -- single or double spacing.

Answer 1

You have to reinstate single spacing in the header:

\makeatletter
\renewcommand\hf@uheadings{%
  \def\@oddhead{\vtop{\linespread{1}%
      \hb@xt@\textwidth{%
        \reset@font{\heading@font\rightmark}\hfil\thepage\strut}%
      \vskip2pt\hrule\vskip-2.4pt}}%
  \let\@oddfoot\@empty
  \def\@evenhead{\vtop{\linespread{1}%
      \hb@xt@\textwidth{%
        \reset@font\strut\thepage\hfil\heading@font\leftmark}%
      \vskip2pt\hrule\vskip-2.4pt}}%
  \let\@evenfoot\@empty
  }
\makeatother
\pagestyle{uheadings}