[Tex/LaTex] Get unicolor background navigation bar in Beamer’s singapore theme

Question

I would like to get the background color of the navigation bar in a single color rather than the default color gradient. Is there any way to do this?

Answer 1

Singapore uses a vertical shading defined as

\pgfdeclareverticalshading{beamer@headfade}{\paperwidth}
  {%
    color(0cm)=(bg);
    color(1.25cm)=(section in head/foot.bg)%
  }

To get a solid color, you can redefine the shading to use only one color, as the following example demonstrates (of course, instead of structure.fg!25!bg you can use whatever color you wish):

\documentclass{beamer}
\usetheme{Singapore}

\makeatletter
\AtBeginDocument{%
  {
    \usebeamercolor{section in head/foot}
  }
  \pgfdeclareverticalshading{beamer@headfade}{\paperwidth}
  {%
    color(0cm)=(structure.fg!25!bg);
    color(1.25cm)=(structure.fg!25!bg)%
  }
  \setbeamercolor{section in head/foot}{bg=}
}
\addtoheadtemplate{\pgfuseshading{beamer@headfade}\vskip-1.25cm}{}
\makeatother


\begin{document}

\begin{frame}
\tableofcontents
\end{frame}

\section{Test section one}
\begin{frame}test\end{frame}

\section{Test section two}
\begin{frame}test\end{frame}

\section{Test section three}
\begin{frame}test\end{frame}

\end{document}

The result: