For bigger font in Swift UIPickerView row, should I replace titleForRow with viewForRow, or add viewForRow in addition to titleForRow?

My two column (ie. 2 component) picker works great.
But some rows are truncated because picker doesn't have enough room for some rows.

All the online guides recommend:

func pickerView(pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusingView view: UIView!)

But, I'm confused: do I replace titleForRow with viewForRow, or add viewForRow in addition to titleForRow?