BlendModes.swift

import SwiftUI

extension BlendMode: Identifiable, CaseIterable {
    
    public var id: Self { self }
    public static var allCases: [BlendMode] {
        [.color, .colorBurn, .colorDodge,
            .darken, .destinationOut, .destinationOver,
            .difference, .exclusion, .hardLight,
            .hue, .lighten, .luminosity,
            .multiply, .normal, .overlay,
            .plusDarker, .plusLighter, .saturation,
            .screen, .softLight, .sourceAtop]
    }
}

struct ContentView: View {
    @State var blendMode = BlendMode.color
    var body: some View {
        List {
            Section("Blend Mode") {
                Picker("", selection: $blendMode) {
                    ForEach(BlendMode.allCases) { mode in
                        Text(String(describing: mode))
                    }
                }
            }
            Section("Demo") {
                ZStack {
                    Text("View One")
                        .padding()
                        .background(Color.green)
                        .foregroundColor(.white)
                        .blendMode(blendMode)
                    Text("View Two")
                        .offset(x: 15, y: 15)
                        .padding()
                        .background(Color.blue)
                        .foregroundColor(.white)
                        .blendMode(blendMode)
                }
            }
        }
    }
}