Android Question B4XDateTemplate: How to disable all days earlier than current date

Sub Button1_Click
    Wait For (GetDate) Complete (Ticks As Long)
    If Ticks > 0 Then
        Log($"Selected date: $Date{Ticks}"$)
    End If
End Sub

Private Sub GetDate() As ResumableSub
    Do While True
        Wait For (dialog.ShowTemplate(DateTemplate, "", "", "Cancel")) Complete (Result As Int)
        Dim zero As Long = 0 'type must be exact
        If Result = xui.DialogResponse_Cancel Then Return zero
        Dim Days As Int = DateUtils.PeriodBetweenInDays(DateTime.Now, DateTemplate.Date).Days
        If Days<0 Then
            DateTemplate.Date = DateTime.Now
            Wait For (dialog.Show("Invalid date", "Ok", "", "")) Complete (Result As Int)
        Else
            Return DateTemplate.Date
        End If
    Loop
    Return 0
End Sub