SwiftUI : Converting Int16 to String - swiftui

Question

I'm learning Swift and I have problems displaying the result of a PickerTextField as an String instead of an Int16...
I'm Using an Int16 because I want to save it to core data...
To pick the Int16 I'm using a pickertextfield:
struct PickerTextField: UIViewRepresentable{
private let textField = UITextField()
private let pickerView = UIPickerView()
private let helper = Helper()
var data: [String]
var placeholder: String
#Binding var lastSelectedIndex: Int16?
func makeUIView(context: Context) -> UITextField {
self.pickerView.delegate = context.coordinator
self.pickerView.dataSource = context.coordinator
self.textField.placeholder = self.placeholder
self.textField.inputView = self.pickerView
//Configure Accesory View
let toolbar = UIToolbar()
toolbar.sizeToFit()
let flexibleSpace = UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: nil, action: nil)
let doneButton = UIBarButtonItem(title: "Done", style: .plain, target: self.helper, action: #selector(self.helper.doneButtonAction))
toolbar.setItems([flexibleSpace, doneButton], animated: true)
doneButton.tintColor = UIColor.black
self.textField.inputAccessoryView = toolbar
self.helper.doneButtonTapped = {
if self.lastSelectedIndex == nil {
self.lastSelectedIndex = 0
}
self.textField.resignFirstResponder()
}
return self.textField
}
func updateUIView(_ uiView: UITextField, context: Context) {
if let lastSelectedIndex = self.lastSelectedIndex {
uiView.text = self.data[Int(lastSelectedIndex)]
}
}
func makeCoordinator() -> Coordinator {
return Coordinator(data: self.data) { (index) in
self.lastSelectedIndex = Int16(index)
}
}
class Helper {
public var doneButtonTapped: (() -> Void)?
#objc func doneButtonAction() {
self.doneButtonTapped?()
}
}
class Coordinator: NSObject, UIPickerViewDelegate, UIPickerViewDataSource {
private var data: [String]
private var didSelectItem: ((Int) -> Void)?
init(data: [String], didSelectItem: ((Int) -> Void)? = nil) {
self.data = data
self.didSelectItem = didSelectItem
}
func numberOfComponents(in pickerView: UIPickerView) -> Int {
return 1
}
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return self.data.count
}
func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
return self.data[row]
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
self.didSelectItem?(row)
}
}
}
And this is the UI to pick a from the pickertextfield...
struct PickerView: View {
#State private var lastSelectedIndex: Int16?
var body: some View {
VStack{
// Text...
Text("Choose a Color!")
//Picker...
PickerTextField(data: ["Red", "Green", "Blue"], placeholder: "Choose a Color!", lastSelectedIndex: self.$lastSelectedIndex)
}
}
}
Is there a way to convert this 'lastSelectedIndex'(Int16) to an String?

Answer 1

try something like this:
struct PickerView: View {
#State private var lastSelectedIndex: Int16? = 0
var body: some View {
VStack (spacing: 55) {
// for testing
Text("lastSelectedIndex = " + String(lastSelectedIndex ?? 0)) // <--- here
// Text...
Text("Choose a Color!")
//Picker...
PickerTextField(data: ["Red", "Green", "Blue"],
placeholder: "Choose a Color!",
lastSelectedIndex: $lastSelectedIndex)
}
}
}
or
struct PickerView: View {
#State private var lastSelectedIndex: Int16? = 0
#State private var lastSelectedIndexString = "0"
var body: some View {
VStack (spacing: 55) {
// for testing
Text("lastSelectedIndex = " + String(lastSelectedIndex ?? 0)) // <-- here
// Text...
Text("Choose a Color!")
//Picker...
PickerTextField(data: ["Red", "Green", "Blue"],
placeholder: "Choose a Color!",
lastSelectedIndex: $lastSelectedIndex)
}.onAppear {
lastSelectedIndexString = String(lastSelectedIndex ?? 0) // <-- here
}
}
}
Or, using a computed property, such as:
struct PickerView: View {
#State private var lastSelectedIndex: Int16? = 0
var lastSelectedIndexString: String { // <-- here
String(lastSelectedIndex ?? 0)
}
var body: some View {
VStack (spacing: 55) {
// for testing
Text("lastSelectedIndexString = " + lastSelectedIndexString) // <-- here
// Text...
Text("Choose a Color!")
//Picker...
PickerTextField(data: ["Red", "Green", "Blue"],
placeholder: "Choose a Color!",
lastSelectedIndex: $lastSelectedIndex)
}
}
}