在Swift中与NSNumberFormatter作斗争

I am creating a budget app that allows the user to input their budget as well as transactions. I need to allow the user to enter both pence and pounds from separate text fields and they need to be formatted together with currency symbols. I have this working fine at the moment but would like to make it localised as currently it only works with GBP. I have been struggling to covert NSNumberFormatter examples from Objective C to Swift.I am creating a budget app that allows the user