For Swift UI: a simple text field character counter with return value into another text field.

Text Field Character Count.swift

import SwiftUI
import Combine


class TextCountMgr: ObservableObject {
	@Published var counted = "0"
	@Published var text = "" {
		didSet {
			counted = String(text.count)
		}
	}
}


struct TextCounterTestView: View {
	@ObservedObject var textCountMgr = TextCountMgr()
	
	var body: some View {
		VStack {
			VStack {
				TextField("Placeholder", text: $textCountMgr.text)
			}
			.padding(.all)
			.background(Color.blue)
			.foregroundColor(.white)
			
			VStack {
				Text("\(textCountMgr.counted)")
			}
		}
	}
}

struct TextCounterTestView_Previews: PreviewProvider {
	static var previews: some View {
		TextCounterTestView()
	}
}