A wxTextCtrl with an initial italics help text, removed when user starts typing.
void SetValue(const wxString &value) override
Ignored if pristine, use ChangeValue if need be.
void SetHelp(const std::string &help_text)
Set help text, enter pristine state.
void RestoreHelp()
Restore help text to initial value, enter pristine state.
bool IsPristine() const
Return true if user has not entered anything.
void ChangeValue(const wxString &value) override
Falsify pristine state.