Change SwiftUI Picker segment Tint/Text Colors

Question

I have a question about changing SwiftUI segment picker colors.

struct SwithBarView: View {
    
    //@State private var preselectedIndex = 0
    @Binding var preselectedIndex: Int
    @State private var selection = ["Selection1", "Selection2"]
    
    init() {
        UISegmentedControl.appearance().selectedSegmentTintColor = .green
        UISegmentedControl.appearance().backgroundColor =
        UIColor(Color.green.opacity(0.3))
        UISegmentedControl.appearance().setTitleTextAttributes([.foregroundColor: UIColor(Color.blue)], for: .selected)
        UISegmentedControl.appearance().setTitleTextAttributes([.foregroundColor: UIColor(Color.secondary)], for: .normal)
    }
    
    var body: some View {
        VStack {
            Picker("You Selection", selection: $preselectedIndex) {
                ForEach(selection.indices, id: \.self) { index in
                    Text(selection[index])
                        .tag(index)
                        .foregroundColor(Color.theme.accent)
                }
            }
            .pickerStyle(SegmentedPickerStyle())
        }
        .padding()
    }
}

The code works well if I remove the init() closure. But with the init() part, an error message shows up "Return from initializer without initializing all stored properties". I think that is due to the @Binding variable. Is there any method to fix this error? Thanks!

Answer 1

Your binding is not initialised, so you have to add it in init arguments, like

struct SwithBarView: View {
    
    @Binding var preselectedIndex: Int
    @State private var selection = ["Selection1", "Selection2"]
    
    init(preselectedIndex: Binding<Int>) {
       self._preselectedIndex = preselectedIndex   // << here !!

       // ... other code