SwiftUI UITextView Coordinator not working - swiftui

Question

I have wrapped a UITextView in a UIViewRepresentable and included a Coordinator as UITextViewDelegate, but the events are not called. What am I doing wrong?
struct TextView : UIViewRepresentable {
typealias UIViewType = UITextView
var placeholder : String
#Binding var text: String
func makeCoordinator() -> Coordinator {
Coordinator(self)
}
func makeUIView(context: UIViewRepresentableContext<TextView>) -> UITextView {
let textView = UITextView()
let placeholderLabel = UILabel()
textView.font = UIFont(name: "Helvetica", size: 16)
placeholderLabel.restorationIdentifier = "Placeholder"
placeholderLabel.text = self.placeholder
placeholderLabel.font = UIFont.italicSystemFont(ofSize: (textView.font?.pointSize)!)
placeholderLabel.sizeToFit()
textView.addSubview(placeholderLabel)
placeholderLabel.frame.origin = CGPoint(x: 25, y: (textView.font?.pointSize)! / 2 + 12)
placeholderLabel.textColor = UIColor.lightGray
placeholderLabel.isHidden = !textView.text.isEmpty
return textView
}
func updateUIView(_ uiView: UITextView, context: UIViewRepresentableContext<TextView>) {
uiView.text = self.text
}
class Coordinator : NSObject, UITextViewDelegate {
var parent: TextView
init(_ uiTextView: TextView) {
self.parent = uiTextView
}
func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
print("Not working")
return true
}
func textViewDidChange(_ textView: UITextView) {
print("Not working")
}
}
}

Answer 1

This is a working example in Xcode Version 11.0 beta 6:
import SwiftUI
struct ContentView: View {
#State var text = ""
var body: some View {
VStack {
Text("text is: \(text)")
TextView(
text: $text
)
.frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity)
}
}
}
struct TextView: UIViewRepresentable {
#Binding var text: String
func makeCoordinator() -> Coordinator {
Coordinator(self)
}
func makeUIView(context: Context) -> UITextView {
let myTextView = UITextView()
myTextView.delegate = context.coordinator
myTextView.font = UIFont(name: "HelveticaNeue", size: 15)
myTextView.isScrollEnabled = true
myTextView.isEditable = true
myTextView.isUserInteractionEnabled = true
myTextView.backgroundColor = UIColor(white: 0.0, alpha: 0.05)
return myTextView
}
func updateUIView(_ uiView: UITextView, context: Context) {
uiView.text = text
}
class Coordinator : NSObject, UITextViewDelegate {
var parent: TextView
init(_ uiTextView: TextView) {
self.parent = uiTextView
}
func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
return true
}
func textViewDidChange(_ textView: UITextView) {
print("text now: \(String(describing: textView.text!))")
self.parent.text = textView.text
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}

Answer 2

You have to add textView.delegate = context.coordinator to makeUIView to register the coordinator to receive updates from UITextView.