# Floating tcolorbox environment in another tcolorbox

I defined a new environment with \newtcolorbox in the preamble. If I call it in the document I can use it. That´s fine!

\documentclass{article}

% Standard Packages
\usepackage[utf8]{inputenc}
\usepackage[ngerman]{babel}
\usepackage[T1]{fontenc}
\usepackage{graphicx, subfig}
\graphicspath{{img/}}
\usepackage[theorems,skins,breakable]{tcolorbox}
\tcbuselibrary{breakable, skins, raster}
\usepackage{lipsum}

\newtcolorbox[blend into=figures]{myfigure}[2][]{float=htb,capture=hbox,
blend before title=dash hang,title={#2},every float=\centering,#1}

\begin{document}

\begin{tcolorbox}[breakable]
\lipsum{}
\end{tcolorbox}

\begin{myfigure}{A tcolorbox figure with quite a long title}
\includegraphics[height=5cm]{modulation.png}
\end{myfigure}

\end{document}


Now I want to integrate the myfigure-Environment into the tcolorbox, like this:

\begin{tcolorbox}[breakable]
\lipsum{}
\begin{myfigure}{A tcolorbox figure with quite a long title}
\includegraphics[height=5cm]{modulation.png}
\end{myfigure}
\end{tcolorbox}


Why is this not possible? What means the error-messages:

• Not in outer par mode. \end{myfigure}

• Undefined control sequence. \end{myfigure}

• Missing number, treated as zero. \end{myfigure}

Can somebody help me to configure it right?

• Welcome to TeX.SX! You cannot use a float within a breakable box. Aug 23 '18 at 8:21
• Thankyou. So what have I have to do, to get the result I want? Aug 23 '18 at 8:26
• What is the expected result? If you have a breakable outer box you must disable floating for the inner box. Aug 23 '18 at 8:29

You cannot have a float within a breakable box. But as you allow options to be passed to the floating box, you can do the following (disabling float once):

\documentclass{article}

% Standard Packages
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{graphicx}
\usepackage[theorems,skins,breakable]{tcolorbox}
\tcbuselibrary{breakable, skins, raster}
\usepackage{lipsum}

\newtcolorbox[blend into=figures]{myfigure}[2][]{float=htb,capture=hbox,
blend before title=dash hang,title={#2},every float=\centering,#1}

\begin{document}

\begin{tcolorbox}[breakable]
\lipsum{}
\begin{myfigure}[nofloat]{A tcolorbox figure with quite a long title}
\includegraphics[height=5cm]{example-image}
\end{myfigure}
\end{tcolorbox}

\end{document}