How to call a method when a Binding changes using UIKit objects wrapped un UIViewRepresentable? - data-binding

Question

Here's the top of the view hierarchy. There are two objects SUIScrollHistory which is a UIViewControllerRepresentable wrapper around a UIKit PageViewController. And there is a DateField which is a UIViewRepresentable wrapper around a UIKit TextField that has a custom inputView. Both those objects have #Binding var date: Date. The binding is only updating inside the UITextField code and does not propagate outside of the UIViewRepresentable and UIViewController representable. I need to call a method on both objects when the Bindind<Date> changes. Any suggestions?
import SwiftUI
struct TestUI: View
{
#State var date: Date = Date() {
didSet {
print("Tabs date didSet")
}
}
var body: some View {
NavigationView {
SUIScrollHistory(date: $date)
.edgesIgnoringSafeArea(.top)
.navigationBarTitle("History")
.navigationBarItems(trailing: DateField(date: $date))
}
}
}
Here's the ScrollView wrapped in UIViewControllerRepresentable.
import UIKit
import SwiftUI
import CoreData
final class SUIScrollHistory: UIViewControllerRepresentable
{
#Binding var date: Date {
willSet {
print("SUI scroll history willSet:")
print("scroll to appropriate pg")
print("NOT CALLED")
}
}
init(date: Binding<Date>) {
self._date = date
}
func makeUIViewController(context: Context) -> ScrollHistory {
return ScrollHistory(date: _date)
}
func updateUIViewController(_ uiViewController: ScrollHistory, context: Context) {
//test
}
}
import UIKit
import SwiftUI
import CoreData
class ScrollHistory: UIPageViewController, UIPageViewControllerDelegate, UIPageViewControllerDataSource
{
#Binding var date: Date {
willSet {
scrollTo(newDate: newValue)
print("scroll history willSet")
print("scroll to appropriate pg")
print("NOT CALLED")
}
}
init(date: Binding<Date>) {
self._date = date
super.init(transitionStyle: .scroll, navigationOrientation: .horizontal, options: nil)
self.setViewControllers( [ UIHostingController(rootView: Rectangle().overlay(Color.blue)) ], direction: .forward, animated: true, completion: nil)
self.delegate = self
self.dataSource = self
self.view.isUserInteractionEnabled = true
self.title = "Mon, Aug 17"
}
required init?(coder: NSCoder) { fatalError() }
func scrollTo(newDate: Date) {
if newDate > date { //Slide the PageVC left if date > currentDay
//let nextDay = date.nextDay()
let edibleJournalTVC = UIHostingController(rootView: Text("inject date"))
self.setViewControllers([edibleJournalTVC], direction: .forward, animated: true, completion: nil)
}
if newDate < date { //Slide the PageVC right if date < currentDay
//let previousDay = date.previousDay()
let edibleJournalTVC = UIHostingController(rootView: Text("inject date")) //self.fdPg(date: date) //FIXME: = FoodPage(date: previousDay)
self.setViewControllers([edibleJournalTVC], direction: .reverse, animated: true, completion: nil)
}
self.date = newDate //TODO: Does this loop infinitely?
}
func pageViewController(_ pageViewController: UIPageViewController, didFinishAnimating finished: Bool, previousViewControllers: [UIViewController], transitionCompleted completed: Bool) {
//update DateField
}
func pageViewController(_ pageViewController: UIPageViewController, viewControllerBefore viewController: UIViewController) -> UIViewController? {
let foodPage = UIHostingController(rootView: Text("inject date")) //FIXME: Binding<Date>(previousDay)))
return foodPage
}
func pageViewController(_ pageViewController: UIPageViewController, viewControllerAfter viewController: UIViewController) -> UIViewController? {
let foodPage = UIHostingController(rootView: Text("inject date")) //FIXME nextDay))
return foodPage
}
}
Here's the DateField which is wrapped in UIViewRepresentable.
import SwiftUI
import UIKit
struct DateField: UIViewRepresentable
{
#Binding var date: Date {
willSet {
print("DateField willSet")
print("NOT CALLED")
}
didSet {
print("DateField didSet")
print("NOT CALLED")
}
}
private let format: DateFormatter
init(date: Binding<Date>, format: DateFormatter = YMDFormat()) {
self._date = date
self.format = format
}
func makeUIView(context: UIViewRepresentableContext<DateField>) -> UITextField {
let tf = DateTextField(date: $date) //FIXME: not injected bcs it's a wrapper
print("makeUIView")
return tf
}
func updateUIView(_ uiView: UITextField, context: UIViewRepresentableContext<DateField>) {
print("updateUIView")
uiView.text = format.string(from: date)
}
}
import SwiftUI
import UIKit
class DateTextField: UITextField
{
#Binding var date: Date {
willSet {
print("DateTextField Date")
print("Is Called")
}
}
private lazy var pickDate: UIDatePicker = { return UIDatePicker() }()
init(date: Binding<Date>) {
self._date = date
super.init(frame: .zero)
self.pickDate.date = date.wrappedValue
self.pickDate.addTarget(self, action: #selector(dateChanged(_:)), for: .valueChanged)
self.inputView = pickDate
self.textColor = .black
}
required init?(coder: NSCoder) { fatalError() }
#objc func dateChanged(_ sender: UIDatePicker) {
self.date = sender.date
}
}
import Foundation
class YMDFormat: DateFormatter
{
override init() {
super.init()
dateFormat = "yyyy-MM-dd"
}
required init?(coder: NSCoder) { fatalError() }
}