我正在寻找具有以下功能的定义（或类似）环境：
- 编号
- 清单
- 定义标题及编号位于描述上方
- 带有黑色边框的框内的定义文本
它应该看起来像下面的例子：
我尝试使用amsthm和thmtools（具有\newframedtheorem，但标题也被框架）并且喜欢它们的编号功能，但无法调整样式。
答案1
类似的东西（基于）？如果您不需要或不喜欢这些选项，tcolorbox可以将其删除。cleveref
\documentclass{report}
\usepackage[most]{tcolorbox}
\usepackage{lipsum,cleveref}
\newtcbtheorem[auto counter,number within=chapter,
crefname={definition}{definitions},Crefname={Definition}{Definitions}% only for cleveref
]{mydef}{Definition}{%
enhanced,frame hidden,coltitle=black,fonttitle=\bfseries,
interior style={fill=none,draw=black,line width=0.6pt},
left=0mm,right=0mm,top=0mm,bottom=0mm,arc=0pt,outer arc=0pt,
terminator sign colon}{def}
\begin{document}
\chapter{First chapter}
See something in \Cref{def:AREF} or \Cref{def:BREF}.
\begin{mydef}{}{AREF}
\lipsum[1]
\end{mydef}
\begin{mydef}{}{BREF}
\lipsum[2]
\end{mydef}
\end{document}
第一个示例代码将框与周围的文本对齐。或者，框中的文本可以与正常的页面内容对齐。以下代码显示了另一种实现，如果您需要的话，它可能更适合打破框。最后，给出了定义列表。
\documentclass{report}
\usepackage[most]{tcolorbox}
\usepackage{lipsum,cleveref}
\newtcbtheorem[auto counter,number within=chapter,list inside=mytheorems,
crefname={definition}{definitions},Crefname={Definition}{Definitions}% only for cleveref
]{mydef}{Definition}{%
enhanced jigsaw,breakable,oversize,interior hidden,colframe=black,
boxrule=0.6pt,left=0mm,right=0mm,top=0mm,bottom=0mm,arc=0pt,outer arc=0pt,boxsep=1mm,
terminator sign colon,description delimiters parenthesis,separator sign none,
detach title,coltitle=black,fonttitle=\bfseries,
enlarge top by=1.2\baselineskip,enlarge top at break by=0mm,pad at break=0mm,
overlay unbroken and first={\node[anchor=base west,inner sep=1mm,outer sep=0.6pt,yshift=4pt]
at (frame.north west) {\tcbtitle};},
}{def}
\begin{document}
\chapter{First chapter}
See something in \Cref{def:AREF}, \Cref{def:BREF} or \Cref{def:CREF}.
\begin{mydef}{My title}{AREF}
\lipsum[1]
\end{mydef}
\lipsum[2]
\begin{mydef}{}{BREF}
\lipsum[3]
\end{mydef}
\lipsum[4]
\begin{mydef}{Another one}{CREF}
\lipsum[5]
\end{mydef}
\tcblistof[\chapter]{mytheorems}{List of Definitions and Theorems}
\end{document}
更新：
或者，使用以下更优雅的代码来实现相同的输出tcolorbox v3.00 (2014/05/08)：
\documentclass{report}
\usepackage[many]{tcolorbox}% version 3.00 (2014/05/09) and above
\usepackage{lipsum,cleveref}
\newtcbtheorem[auto counter,number within=chapter,list inside=mytheorems,
crefname={definition}{definitions},Crefname={Definition}{Definitions}% only for cleveref
]{mydef}{Definition}{%
enhanced jigsaw,breakable,oversize,interior hidden,colframe=black,
boxrule=0.6pt,left=0mm,right=0mm,top=0mm,bottom=0mm,arc=0pt,outer arc=0pt,boxsep=1mm,pad at break=0pt,
terminator sign colon,description delimiters parenthesis,separator sign none,
attach boxed title to top left={yshift=-1mm},minipage boxed title,
boxed title style={empty,boxrule=0.6pt,left=0mm,right=0mm,top=0mm,bottom=0mm,boxsep=1mm},
coltitle=black,fonttitle=\bfseries,before title=\strut}{def}
\begin{document}
\chapter{First chapter}
See something in \Cref{def:AREF}, \Cref{def:BREF} or \Cref{def:CREF}.
\begin{mydef}{My title}{AREF}
\lipsum[1]
\end{mydef}
\lipsum[2]
\begin{mydef}{}{BREF}
\lipsum[3]
\end{mydef}
\lipsum[4]
\begin{mydef}{Another one}{CREF}
\lipsum[5]
\end{mydef}
\tcblistof[\chapter]{mytheorems}{List of Definitions and Theorems}
\end{document}
答案2
另一种选择是使用mdframed这次：
\documentclass{report}
\usepackage{amsmath}
\usepackage[framemethod=tikz]{mdframed}
\usepackage{lipsum}
\newcounter{defi}
\numberwithin{defi}{chapter}
\newmdenv[
settings={\refstepcounter{defi}},
singleextra={
\node[
overlay,
inner xsep=0pt,
anchor=south west,
font=\bfseries
] at ([xshift=5pt]O|-P) {Definition~\thedefi:};
},
firstextra={
\node[
overlay,
inner xsep=0pt,
anchor=south west,
font=\bfseries
] at ([xshift=5pt]O|-P) {Definition~\thedefi:};
},
skipabove=4.5ex,
innerleftmargin=5pt,
innerrightmargin=5pt,
leftmargin=-5pt,
rightmargin=-5pt,
]{mydef}
\begin{document}
\chapter{Test chapter}
\begin{mydef}
\lipsum[4]
\end{mydef}
\lipsum[4]
\begin{mydef}
\lipsum[2]
\end{mydef}
\end{document}
