Android Question PreferencesDialog Boolean

prefdialog.AddTextItem("First", "First Name")
    prefdialog.AddTextItem("Last",  "Last Name")
    prefdialog.AddDateItem("Date",  "Date")
    prefdialog.AddTimeItem("Time",  "Time")
    prefdialog.AddBooleanItem("Alive","Alive")        '<---------See

Dim Data As Map = CreateMap("First": "","Last": "", "Date":DateTime.Now, "Time": Null, "Alive": True)     '<---------Here