SwiftUI @binding and @State properties with custom initialization

BindingSample.swift

import SwiftUI

struct CustomDatePickerExample: View {
    
    @Binding private var currentDate: Date
    
    @State private var currentYear: Int
    @State private var currentMonth: Int
    
    var body: some View {
        VStack (spacing: 12) {
            HStack {
                Spacer()
                Button {
                    guard currentYear > 0 else { return }
                    currentYear -= 1
                } label: {
                    Image(systemName: "chevron.left")
                }.disabled(1 == currentYear)
                Text(currentYear.formatted(.number.grouping(.never)))
                Button {
                    currentYear += 1
                } label: {
                    Image(systemName: "chevron.right")
                }
                Spacer()
                
            }
            HStack {
                Text(Calendar.autoupdatingCurrent.monthSymbols[currentMonth - 1])
                Spacer()
                Button {
                    guard currentMonth > 1 else { return }
                    currentMonth -= 1
                } label: {
                    Image(systemName: "chevron.left")
                }.disabled(1 == currentMonth)
                Button {
                    guard currentMonth < 12 else { return }
                    currentMonth += 1
                } label: {
                    Image(systemName: "chevron.right")
                }.disabled(12 == currentMonth)
            }
            Text(currentDate.formatted(date: .abbreviated, time: .omitted))

        }
        .padding()
    }
    
    init(currentDate: Binding<Date>) {
        
        self._currentDate = currentDate
        
        let date = currentDate.wrappedValue
        let year: Int = Calendar.autoupdatingCurrent.component(.year, from: date)
        let month: Int = Calendar.autoupdatingCurrent.component(.month, from: date)
        
        self._currentYear = State(initialValue: year)
        self._currentMonth = State(initialValue: month)
        
    }
    
}

struct ParentView: View {
    @State var currentDate: Date = Date()
    var body: some View {
        CustomDatePickerExample(currentDate: $currentDate)
    }
}

struct CustomDatePickerExample_Previews: PreviewProvider {
    static var previews: some View {
        ParentView()
    }
}