LongPressContentView.swift

import SwiftUI

struct ContentView: View {
  
  static let defaultColour = Color.blue
  static let pressedColour = Color.red
  static let completeColour = Color.green
  
  @State var buttonColour = Self.defaultColour
  
  var body: some View {
    VStack {
      Text("Press")
        .font(.largeTitle)
        .foregroundColor(.white)
        .padding()
        .background(buttonColour)
        .cornerRadius(15)
        .onLongPressGesture(minimumDuration: 3, maximumDistance: 150) {
          buttonColour = Self.completeColour
        } onPressingChanged: { pressed in
          buttonColour = pressed ? Self.pressedColour : Self.defaultColour
        }
      Button("Reset") { buttonColour = Self.defaultColour }
    }
  }
}