Shadings in head

Question

I am currently trying to code in beamer the following image. So far I got the three beamercolorbox but I can't get the shaded background.

Here is the aspect I want:

\documentclass[xcolor=dvipsnames,14pt]{beamer}
\usepackage[english]{babel}
\usepackage[latin1]{inputenc}
\usepackage{tikz}
\usetikzlibrary{positioning,shapes}
\usetikzlibrary{calc}
\setlength\fboxsep{0pt}
\setlength\fboxrule{0.5pt}
\setlength\parskip{0.75em}
\setlength\parindent{0pt}
\setbeamersize{text margin left=3mm,text margin right=3mm}{}
\setbeamerfont{section in head/foot}{size=\scriptsize}
\setbeamerfont{subsection in head/foot}{size=\scriptsize}
\setbeamerfont{date in head/foot}{size=\scriptsize}
\setbeamercolor{section in head/foot}{fg=black,bg=gray}
\setbeamercolor{subsection in head/foot}{fg=black,bg=gray}
\setbeamercolor{date in head/foot}{fg=black,bg=gray}
\setbeamertemplate{headline}{
\leavevmode\hbox{%
\begin{beamercolorbox}[wd=54mm,ht=3ex,dp=1ex,right]{section in head/foot}%
\usebeamerfont{section in head/foot}\insertsectionhead\hspace*{2ex}%
\end{beamercolorbox}%
\begin{beamercolorbox}[wd=65mm,ht=3ex,dp=1ex,right]{subsection in head/foot}%
\usebeamerfont{subsection in head/foot}\insertsubsectionhead\hspace*{2ex}%
\end{beamercolorbox}%
\begin{beamercolorbox}[wd=9mm,ht=3ex,dp=1ex,right]{date in head/foot}%
\usebeamerfont{date in head/foot}\insertframenumber{}\hspace*{2ex}%
\end{beamercolorbox}%
}\vskip0pt}

\begin{document}
\section{Section title}
\subsection{Subsection title}
\begin{frame}
\frametitle{Frame title}
some text
\end{frame}
\end{document}

Solution: In fact, I just had to put the shadings in a hbox and use \hskip and \vskip. Here is the solution:

\setbeamertemplate{headline}{
\leavevmode%
\hskip-1mm\hbox{%
\pgfdeclarehorizontalshading{beamer@topshade}{4ex}{
color(0mm)=(headsectionback1); 
color(54mm)=(headsectionback2);
color(54.001mm)=(headsubsectionback1); 
color(119mm)=(headsubsectionback2);
color(119.001mm)=(headpageback); 
color(128mm)=(headpageback)}
\pgfuseshading{beamer@topshade}
}\hskip-128mm\vskip-4ex%
\hbox{%
\begin{beamercolorbox}[wd=54mm,ht=3ex,dp=1ex,right]{section in head/foot}%
\usebeamerfont{section in head/foot}\insertsectionhead\hspace*{2ex}
\end{beamercolorbox}%
\begin{beamercolorbox}[wd=65mm,ht=3ex,dp=1ex,right]{subsection in head/foot}%
\usebeamerfont{subsection in head/foot}\insertsubsectionhead\hspace*{2ex}
\end{beamercolorbox}%
\begin{beamercolorbox}[wd=9mm,ht=3ex,dp=1ex,right]{date in head/foot}%
\usebeamerfont{date in head/foot}\insertframenumber{}\hspace*{2ex}
\end{beamercolorbox}%
}\vskip0pt%
}

Answer 1

Let's assume the so called shaded background be placed in the headline template.

In this case, the answer provides a method to insert a vertical shaded background or a simple background.

Simple background

\documentclass[xcolor=dvipsnames,14pt]{beamer}
\usepackage[english]{babel}
\usepackage[latin1]{inputenc}
\usepackage{tikz}
\usetikzlibrary{positioning,shapes}
\usetikzlibrary{calc}
\setlength\fboxsep{0pt}
\setlength\fboxrule{0.5pt}
\setlength\parskip{0.75em}
\setlength\parindent{0pt}
\setbeamersize{text margin left=3mm,text margin right=3mm}{}
\setbeamerfont{section in head/foot}{size=\scriptsize}
\setbeamerfont{subsection in head/foot}{size=\scriptsize}
\setbeamerfont{date in head/foot}{size=\scriptsize}
\setbeamercolor{section in head/foot}{fg=black,bg=gray}
\setbeamercolor{subsection in head/foot}{fg=black,bg=gray}
\setbeamercolor{date in head/foot}{fg=black,bg=gray}

% uniform color
\setbeamercolor{shadedhead}{bg=blue}

\setbeamertemplate{headline}{
\leavevmode\hbox{%
\begin{beamercolorbox}[wd=54mm,ht=3ex,dp=1ex,right]{section in head/foot}%
\usebeamerfont{section in head/foot}\insertsectionhead\hspace*{2ex}%
\end{beamercolorbox}%
\begin{beamercolorbox}[wd=65mm,ht=3ex,dp=1ex,right]{subsection in head/foot}%
\usebeamerfont{subsection in head/foot}\insertsubsectionhead\hspace*{2ex}%
\end{beamercolorbox}%
\begin{beamercolorbox}[wd=9mm,ht=3ex,dp=1ex,right]{date in head/foot}%
\usebeamerfont{date in head/foot}\insertframenumber{}\hspace*{2ex}%
\end{beamercolorbox}%
}\vskip0pt
\leavevmode\hbox{%
% uniform
\begin{beamercolorbox}[wd=\textwidth,ht=3ex,dp=2ex]{shadedhead}%
\end{beamercolorbox}%

}\vskip0pt
}

\begin{document}
\section{Section title}
\subsection{Subsection title}
\begin{frame}
\frametitle{Frame title}
some text
\end{frame}

\begin{frame}
\frametitle{Frame title 2}
some text
\end{frame}

\subsection{Subsection second title}
\begin{frame}
\frametitle{Frame title}
some text
\end{frame}

\begin{frame}
\frametitle{Frame title 2}
some text
\end{frame}
\end{document}

The background has been inserted by means of:

\leavevmode\hbox{%
% uniform
\begin{beamercolorbox}[wd=\textwidth,ht=3ex,dp=2ex]{shadedhead}%
\end{beamercolorbox}%
}

and the color definition could be modified by changing:

\setbeamercolor{shadedhead}{bg=blue}

You can adapt the dimensions in the options of the beamercolorbox environment.

Two frames of the result:

Background with vertical shading

Let's define as first the shading:

% Shade definition
\pgfdeclareverticalshading{mytopshade}{\paperwidth}{%
    color(0pt)=(gray!40);
    color(10pt)=(gray)}

You can find further informations on the possible shadings in the pgfmanual (also related How to create a ball shading and to customize 3D lighting manually?).

Now we apply this shading in the headline template:

\leavevmode\hbox{%
\begin{beamercolorbox}[wd=\textwidth,ht=3ex,dp=2ex]{}%
\begin{pgfpicture}{0pt}{0pt}{\paperwidth}{3ex}
    \pgfpathrectangle{\pgfpointorigin}{\pgfpoint{\paperwidth}{3ex}}
    \pgfusepath{clip}
    \pgftext[left,base]{\pgfuseshading{mytopshade}}
  \end{pgfpicture}
\end{beamercolorbox}%
}

The whole code:

\documentclass[xcolor=dvipsnames,14pt]{beamer}
\usepackage[english]{babel}
\usepackage[latin1]{inputenc}
\usepackage{tikz}
\usetikzlibrary{positioning,shapes}
\usetikzlibrary{calc}
\setlength\fboxsep{0pt}
\setlength\fboxrule{0.5pt}
\setlength\parskip{0.75em}
\setlength\parindent{0pt}
\setbeamersize{text margin left=3mm,text margin right=3mm}{}
\setbeamerfont{section in head/foot}{size=\scriptsize}
\setbeamerfont{subsection in head/foot}{size=\scriptsize}
\setbeamerfont{date in head/foot}{size=\scriptsize}
\setbeamercolor{section in head/foot}{fg=black,bg=gray}
\setbeamercolor{subsection in head/foot}{fg=black,bg=gray}
\setbeamercolor{date in head/foot}{fg=black,bg=gray}

% Shade definition
\pgfdeclareverticalshading{mytopshade}{\paperwidth}{%
    color(0pt)=(gray!40);
    color(10pt)=(gray)}

\setbeamertemplate{headline}{
\leavevmode\hbox{%
\begin{beamercolorbox}[wd=54mm,ht=3ex,dp=1ex,right]{section in head/foot}%
\usebeamerfont{section in head/foot}\insertsectionhead\hspace*{2ex}%
\end{beamercolorbox}%
\begin{beamercolorbox}[wd=65mm,ht=3ex,dp=1ex,right]{subsection in head/foot}%
\usebeamerfont{subsection in head/foot}\insertsubsectionhead\hspace*{2ex}%
\end{beamercolorbox}%
\begin{beamercolorbox}[wd=9mm,ht=3ex,dp=1ex,right]{date in head/foot}%
\usebeamerfont{date in head/foot}\insertframenumber{}\hspace*{2ex}%
\end{beamercolorbox}%
}\vskip0pt
\leavevmode\hbox{%
\begin{beamercolorbox}[wd=\textwidth,ht=3ex,dp=2ex]{}%
\begin{pgfpicture}{0pt}{0pt}{\paperwidth}{3ex}
    \pgfpathrectangle{\pgfpointorigin}{\pgfpoint{\paperwidth}{3ex}}
    \pgfusepath{clip}
    \pgftext[left,base]{\pgfuseshading{mytopshade}}
  \end{pgfpicture}
\end{beamercolorbox}%
}\vskip0pt
}

\begin{document}
\section{Section title}
\subsection{Subsection title}
\begin{frame}
\frametitle{Frame title}
some text
\end{frame}

\begin{frame}
\frametitle{Frame title 2}
some text
\end{frame}

\subsection{Subsection second title}
\begin{frame}
\frametitle{Frame title}
some text
\end{frame}

\begin{frame}
\frametitle{Frame title 2}
some text
\end{frame}
\end{document}

Now the same frames of the previous example are diplayed as: