need code-sample using "NumberFormatter"

Question

Created Jan ’21

Replies 3

Boosts 0

Participants 3

Is there anybody who can show me how to use NumberFormatter.

I would like to use it to transform input from TextField into NSNumber.

Answered by Apfelgruen in 655278022

Dear jjatie

thank you very much, I copied your code and it works well. So I can continue.

Boost

Answer 1

Zurble OP

Jan ’21

this is one example of transferring an amount of payment
I'm using the MVVM design pattern.
In the View.swift file

Code Block struct ContentView: View {
    @State var amount: String = ""
    
    var body: some View {
        VStack(alignment: .leading) {
            TextField("Enter amount...", text: $amount, onEditingChanged: { (changed) in
                print("amount onEditingChanged - \(amount)")
            }) {
                print("amount onCommit")
            }
            
            Text("Your amount: \(amount)")
        }.padding()
    }
}

//NumberFormatter in ViewModel.swift
assuming the variable amount = "USD1,234.57"

Code Block var numberInString = amount
let numberFormatter = NumberFormatter()
numberFormatter.numberStyle = NumberFormatter.Style.currencyISOCode
numberFormatter.locale = Locale(identifier: "en_US")
if let number = numberFormatter.number(from: numberInString) {
	print("this is the final number:", number)
}

Result:
this is final number: 1234.57

0

Answer 2

jjatie OP

Jan ’21

I'm guessing you don't actually want an NSNumber as Swift provides it own number types (Int, Double, etc.). Here is an example that uses Int, though this can be simply modified by setting formatter.allowFloats = true and changing number's type to Double.

Code Block struct ContentView: View {
    static let formatter: NumberFormatter = {
        let formatter = NumberFormatter()
        formatter.allowsFloats = false
        return formatter
    }()
    @State var number: Int = 0
    var body: some View {
        TextField(
            "Number Field",
            value: $number,
            formatter: Self.formatter,
            onCommit: {
                print(number)
            }
        )
        .keyboardType(.numberPad)
        .textFieldStyle(RoundedBorderTextFieldStyle())
        .padding()
    }
}

1

Answer 3

Apfelgruen OP

Jan ’21

Accepted Answer

Dear jjatie

thank you very much, I copied your code and it works well. So I can continue.

0