For Day 19 Challenge, Paul suggests trying to format the unit conversion output..."if you’d like to be a bit fancy with the output number you display, try calling .formatted() on it – e.g. someDouble.formatted(). This will cause iOS to format the number for printing, adding thousands separator and removing a lot of the noise from unnecessary decimal places."

I've tried adding .formated() to my output text field (in 4th section) but keep getting errors (see //comments in code). How would I use .formatted with my output text box to get the result Paul suggests?

struct ContentView: View {
    @State private var conversionValue = 0.0
    @State private var inputUnit = "meters"
    @State private var outputUnit = "feet"

    @FocusState private var valueIsFocused: Bool

    let inputUnitSelection = ["feet", "yards", "miles", "meters", "kilometers"]
    let outputUnitSelection = ["feet", "yards", "miles", "meters", "kilometers"]

    var baseUnitValue: Double {
        var value = 0.0
        switch inputUnit {
        case "feet":
            value = conversionValue / 3.28084
            return value
        case "yards":
            value = conversionValue / 3
            return value
        case "miles":
            value = conversionValue / 5280
            return value
        case "meters":
            value = conversionValue * 1
            return value
        default:
            value = conversionValue / 1000
            return value
        }
    }

    var convertedValue: Double {
        var value = 0.0
        switch outputUnit {
        case "feet":
            value = baseUnitValue * 3.28084
            return value
        case "yards":
            value = baseUnitValue * 1.093613
            return value
        case "miles":
            value = baseUnitValue * 0.0006213712
            return value
        case "meters":
            value = baseUnitValue * 1
            return value
        default:
            value = baseUnitValue / 1000
            return value
        }
    }

    var body: some View {
        NavigationView {
            Form {
                Section {
                    TextField("Value to convert", value: $conversionValue, format: .number)
                        .keyboardType(.decimalPad)
                        .focused($valueIsFocused)
                } header: {
                    Text("Enter conversion value")
                }

                Section {
                    Picker("Unit", selection: $inputUnit) {
                        ForEach(inputUnitSelection, id: \.self) {
                            Text($0)
                        }
                    }
                } header: {
                    Text("Select unit to convert from")
                }

                Section {
                    Picker("Unit", selection: $outputUnit) {
                        ForEach(outputUnitSelection, id: \.self) {
                            Text($0)
                        }
                    }
                } header: {
                    Text("Select unit to convert to")
                }

                Section {
                    Text(convertedValue, format: .number) //Tried format: .formatted() and number.formatted() but gives error
                //  .formatted() here gives errors
                } header: {
                    Text("Converted value")
                }
            }
            .navigationTitle("Unit Converter")
            .toolbar {
                ToolbarItemGroup(placement: .keyboard) {
                    Spacer()

                    Button("Done") {
                        valueIsFocused = false
                    }
                }
            }
        }
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

Instead of this:

Text(convertedValue, format: .number)

do this:

Text(convertedValue.formatted())

You call formatted() on a number to turn it into a String.

Thank you!