如何設定在beamer中可見的frametitle下的字幕框？

Question

我在用這個客製化的投影機風格

但它需要一點點修改才能穩健地工作。當我們的框架沒有字幕時就可以了

\begin{frame}{Introduction}%{My Title}
    some text about Latex
\end{frame}

但在字幕模式下，字幕框變成定義圓的基線，然後往下跳一點。

\begin{frame}{Introduction}{My Title}
    some text about Latex
\end{frame}

為此，我想將字幕框設置為可見，即使它是空的。另一個解決方案是不使用字幕。

\documentclass{beamer}

\definecolor{devryblue}{RGB}{5, 51, 92}    
\makeatletter
\colorlet{beamer@blendedblue}{devryblue}
\makeatother

\usepackage[utf8]{inputenc}
\usepackage{tikz}

\usetheme{Madrid}
\usepackage{default}  

\addtobeamertemplate{frametitle}{}{%
\begin{tikzpicture}[remember picture,overlay]
\fill[devryblue] (10.8,0.6) circle (.9cm);
\clip (10.8,0.6) circle (.75cm);
\node at (10.8,0.6) {\includegraphics[width=2.1cm]{example-image}};
\end{tikzpicture}}

\begin{document}

\section{title}

\begin{frame}
\frametitle{title}
\tableofcontents

\end{frame}

Answer 1

您可以透過相對於頁面定位徽標來避免任何潛在的徽標跳躍：

\documentclass{beamer}

\definecolor{devryblue}{RGB}{5, 51, 92}    
\makeatletter
\colorlet{beamer@blendedblue}{devryblue}
\makeatother

\usepackage[utf8]{inputenc}
\usepackage{tikz}

\usetheme{Madrid}
%\usepackage{default}  

\addtobeamertemplate{frametitle}{}{%
\begin{tikzpicture}[remember picture,overlay]
\coordinate (logo) at ([xshift=-1.5cm,yshift=-1cm]current page.north east);
\fill[devryblue] (logo) circle (.9cm);
\clip (logo) circle (.75cm);
\node at (logo) {\includegraphics[width=2.1cm]{example-image}};
\end{tikzpicture}}

\begin{document}

\section{title}

\begin{frame}
\frametitle{title}
\tableofcontents

\end{frame}

\begin{frame}
\frametitle{title}
\framesubtitle{My Title}
    some text about Latex
\end{frame}


\end{document}