_SetupButton
.Add(_SetupButton("-", kMonthDownMessage, height), 0, 0)
.Add(_SetupButton("+", kMonthUpMessage, height), 2, 0)
.Add(_SetupButton("-", kYearDownMessage, height), 4, 0)
.Add(_SetupButton("+", kYearUpMessage, height), 6, 0)
BButton* _SetupButton(const char* label, uint32 what,