在新环境中使用环境参数不起作用

Question

我知道这一定是一件微不足道的事情：

\documentclass{article}

\usepackage{amsmath}
\usepackage{amsthm}
\usepackage{thmtools}

\usepackage[svgnames]{xcolor}
\usepackage{framed} %http://www.latex-community.org/forum/viewtopic.php?f=44&t=5823
\colorlet{shadecolor}{gray!25}
\renewenvironment{leftbar}{%
  \def\FrameCommand{\textcolor{shadecolor}{\vrule width 3pt} \hspace{10pt}}%
  \MakeFramed {\advance\hsize-\width \FrameRestore}}%
{\endMakeFramed}

\declaretheorem[name=Example]{exampleOri}
\newenvironment{example}[1]{\begin{leftbar}\begin{exampleOri}[#1]}{\end{exampleOri}\end{leftbar}}

\begin{document}

\begin{example}[This is a test]
Bla
\end{example}

\end{document}

结果是Example 1 ([). This is a test] Bla。这里出了什么问题？

更新：由于它不是问题的直接答案，但仍然有用，所以我想使用以下密钥发布我的最终mdframed方法thmtools：

\documentclass{article}

\usepackage{amsmath}
\usepackage{amsthm}
\usepackage{thmtools}
\usepackage[framemethod=TikZ]{mdframed}

\usepackage[svgnames]{xcolor}
\colorlet{shadecolor}{gray!25}

\declaretheorem[name=Example,
    mdframed={
        hidealllines=true,leftline=true,
        rightmargin=0pt,innerrightmargin=0pt,
        innerlinewidth=0pt,middlelinewidth=0pt,
        outerlinecolor=shadecolor,outerlinewidth=3pt,
        skipabove=\topskip,skipbelow=\topskip}
    ]{example}

\begin{document}
\begin{example}[This is a test]
   Bla
\end{example}    
\end{document}

Answer 1

您将该参数声明为example强制参数，因此应将其括在括号中。

\documentclass{article}

\usepackage{amsmath}
\usepackage{amsthm}
\usepackage{thmtools}

\usepackage[svgnames]{xcolor}
\colorlet{shadecolor}{gray!25}

\usepackage{framed}
\renewenvironment{leftbar}{%
  \def\FrameCommand{\textcolor{shadecolor}{\vrule width 3pt} \hspace{10pt}}%
  \MakeFramed {\advance\hsize-\width \FrameRestore}}%
{\endMakeFramed}

\declaretheorem[name=Example]{exampleOri}
\newenvironment{example}[1][]
  {\begin{leftbar}
   \ifx\relax#1\relax
     \begin{exampleOri}
   \else
     \begin{exampleOri}[#1]
   \fi}
  {\end{exampleOri}\end{leftbar}}

\begin{document}

\begin{example}[This is a test]
Bla
\end{example}

\begin{example}
Bla
\end{example}

\end{document}

然而，我会选择一条更简单的路线。

\documentclass{article}

\usepackage{amsmath}
\usepackage{amsthm}

\usepackage[svgnames]{xcolor}
\colorlet{shadecolor}{gray!25}

\usepackage[framemethod=TikZ]{mdframed}
\newmdtheoremenv[hidealllines=true,leftline=true,
  innerlinewidth=0pt,middlelinewidth=0pt,
  outerlinecolor=shadecolor,outerlinewidth=3pt,
  skipabove=\topsep,skipbelow=\topsep,
  ]{example}{Example}

\begin{document}

\begin{example}[This is a test]
Bla
\end{example}

\begin{example}
Bla
\end{example}

\end{document}