\twocolitem{{\bf wxOK}}{Show an OK button.}
\twocolitem{{\bf wxCANCEL}}{Show a Cancel button.}
\twocolitem{{\bf wxYES\_NO}}{Show Yes and No buttons.}
+\twocolitem{{\bf wx\_NO\_DEFAULT}}{Used with {\bf wxYES\_NO}, makes {\bf No} button the default.}
\twocolitem{{\bf wxCENTRE}}{Centre the message. Not Windows.}
\twocolitem{{\bf wxICON\_EXCLAMATION}}{Shows an exclamation mark icon. Windows only.}
\twocolitem{{\bf wxICON\_HAND}}{Shows a hand icon. Windows only.}