animation-example.swift

import SwiftUI

struct ContentView: View {
    @State var tapped: Bool = false
    
    var width: CGFloat { tapped ? 300 : 60 }
    var color: Color { tapped ? .red : .yellow }
    
    var body: some View {
        Button(action: { tapped.toggle() }) {
            ZStack {
                Capsule().foregroundColor(color)
                Image(systemName: "plus")
                    .foregroundColor(.white)
                    .font(.system(size: 25, weight: .bold, design: .rounded))
            }
            .frame(width: width, height: 60, alignment: .leading)
        }.animation(.spring())
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}