In the choice list \textit{abt\/} we want to either choose an entry
from the list or add text.\\
The parameter
\begin{lstlisting}
combo=true
\end{lstlisting}
activates combo box hehaviour.\\
Additionally we add a JavaScript code line
\begin{lstlisting}
this.getField("abt").editable = true;
\end{lstlisting}
into our initialization function \textit{myFirstJavaScriptFunction()\/}.
\lstinputlisting{../examples/ex0011.tex}