Function mg::question

pub fn question<CALLBACK, COMM, SETT, WIDGET>(
    mg: &ContainerComponent<Mg<COMM, SETT>>, 
    relm: &Relm<WIDGET>, 
    msg: String, 
    choices: &'static [char], 
    callback: CALLBACK
) where
    CALLBACK: Fn(Option<String>) -> WIDGET::Msg + 'static,
    COMM: Clone + EnumFromStr + EnumMetaData + SpecialCommand + 'static,
    SETT: Default + EnumMetaData + Settings + SettingCompletion + 'static,
    WIDGET: Widget + 'static, 

Ask a multiple-choice question to the user.