! Paragraph ended before \lst@next was complete: Using lstlisting in itemize

Question

I want to print a piece of verbatim within an item of an itemize environment, as below:

\documentclass[letter, 11pt]{article}
\usepackage{enumitem}
\usepackage{pifont}
\usepackage{listings}

\newcommand{\Question}[1]{{\bfseries?: #1\par\vspace{5pt}}}
\newcommand{\Answer}[1]{\noindent\ding{51}: #1}

\begin{document}

\section*{Problem \#1}
\Question{content
}

\Answer{
\begin{itemize}
    \item[1] Some content.\\
    My Verbatim:
    \begin{lstlisting}
        G = VVVVVVVVVVVVVVVVVVVVVVVVVVV

        PROJ = PPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP
    \end{lstlisting}
\end{itemize}
}
\end{document}

But there is an error:

! Paragraph ended before \lst@next was complete.

I did even try the frame solution, presented here, but it does still not work:

\documentclass[letter, 11pt]{article}
\usepackage{enumitem}
\usepackage{pifont}
\usepackage{listings}

\newcommand{\Question}[1]{{\bfseries?: #1\par\vspace{5pt}}}
\newcommand{\Answer}[1]{\noindent\ding{51}: #1}

\begin{document}

\section*{Problem \#1}
\Question{content
}

\Answer{
\begin{itemize}
    \item[1] Some content.\\
    My Verbatim:
    \begin{frame}[fragile]
        \begin{lstlisting}
            G = VVVVVVVVVVVVVVVVVVVVVVVVVVV

            PROJ = PPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP
        \end{lstlisting}    
    \end{frame}
\end{itemize}
}
\end{document}

Answer 1

Since there seem to be an absolute No way for code improvement (including a change of macros) and manually doing stuff anyways, including numbering, there is nothing much that can be done.

\documentclass[letter, 11pt]{article}
\usepackage{enumitem}
\usepackage{pifont}
\usepackage{listings}

\newcommand{\Question}[1]{{\bfseries?: #1\par\vspace{5pt}}}
\newcommand{\Answer}{\noindent\ding{51}: }

\begin{document}

\section*{Problem \#1}
\Question{content
}

\Answer{
    \begin{itemize}
        \item[1] Some content.\\
            My Verbatim:
            \begin{lstlisting}
            G =
            VVVVVVVVVVVVVVVVVVVVVVVVVVV

            PROJ
            =
            PPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP
            \end{lstlisting}
    \end{itemize}
}
\end{document}

Answer 2

Not an answer to OP's question, but I got to this question when I forgot to add [fragile] to my frame when adding lstlisting code.

Example:

Broken

\begin{frame}
    \begin{lstlisting}[language=Java]
    // single line comment
    \end{lstlisting}
\end{frame}

Fixed

\begin{frame}[fragile]
    \begin{lstlisting}[language=Java]
    // single line comment
    \end{lstlisting}
\end{frame}

Answer 3

The workaround with \input also worked in my case.

I encountered the same error message when trying to use lstlistings within the multiaudience package:

\usepackage{multiaudience}
\SetNewAudience{guests}

\begin{shownto}{guests} 
  \begin{indentcode}
        \begin{lstlisting}
         some text
        \end{lstlisting}
  \end{indentcode}
\end{shownto}

~~~~~~~   example which works   ~~~~~~~~~

\usepackage{multiaudience}
\SetNewAudience{guests}

\begin{shownto}{guests} 
  \begin{indentcode}
        \input{folder/newfile}
  \end{indentcode}
\end{shownto}

with the content of newfile.tex being saved in the 'folder':
    \begin{lstlisting}
         some text
    \end{lstlisting}

Answer 4

What can you control, here?

The issue is with a verbatim environment as the argument to a command. From this question, one solution is to use cprotect:

\documentclass[letter, 11pt]{article}
\usepackage{enumitem,cprotect}
\usepackage{pifont}
\usepackage{listings}

\newcommand{\Question}[1]{{\bfseries?: #1\par\vspace{5pt}}}
\newcommand{\Answer}[1]{\noindent\ding{51}: #1}

\begin{document}

\section*{Problem \#1}
\Question{content
}

\cprotect\Answer{
\begin{itemize}
    \item[1] Some content.\\
    My Verbatim:
        \begin{lstlisting}
            G = VVVVVVVVVVVVVVVVVVVVVVVVVVV

            PROJ = PPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP
        \end{lstlisting}
\end{itemize}
}
\end{document}