Metropolis Beamer theme framesubtitle

README.md

Metropolis framesubtitle

This is an attempt to have frame subtitle support for the Metropolis Beamer theme. Since there is no native support in the theme itself, this is somewhat of a hack.

This adds an extra beamercolorbox, equivalent to a frametitle box, but with a different name.

example.tex

\documentclass{beamer}
\usetheme[progressbar=foot, numbering=none]{metropolis} % Use metropolis theme

%IMPORTANT: include the file
\usepackage{metropolis_framesubtitle}

\definecolor{Purple}{HTML}{911146}

% Set title color
\setbeamercolor{frametitle}{bg=Purple}

% IMPORTANT: set subtitle color
\setbeamercolor{framesubtitle}{fg=Purple, bg=normal text.bg}

\title{A minimal example}
\subtitle{Hello}
\date{\today}
\author{Matthias Vogelgesang}
\institute{Centre for Modern Beamer Themes}
\begin{document}
\maketitle

\begin{frame}{This is title}{This is a subtitle}
Hello, world!
\end{frame}
\begin{frame}{Second Frame}{Another subtitle!}
Goodbye, world!
\end{frame}
\end{document}

metropolis_framesubtitle.sty

\ProvidesPackage{metropolis_framesubtitle}

\addtobeamertemplate{frametitle}{}{%
  \ifx\insertframesubtitle\@empty\else%
  \usebeamerfont{frametitle}%
  \usebeamercolor[fg]{framesubtitle}%

\begin{beamercolorbox}[%
    wd=\paperwidth,%
    sep=0pt,%
    leftskip=\metropolis@frametitle@padding,%
    rightskip=\metropolis@frametitle@padding,%
  ]{framesubtitle}%

  \metropolis@frametitlestrut@start\insertframesubtitle\metropolis@frametitlestrut@end%
\end{beamercolorbox}%
  \fi%
}