swiftui examples

AnimationView.swift

import SwiftUI

struct AnimationView: View {
  @State private var isRecording = false
  @State private var pulseScale: CGFloat  = 1.0
  @State private var pulseOpacity: Double = 0.6
  
  var body: some View {
    ZStack {
      // Pulse rings
      ForEach(0..<40) { i in
        Circle()
          .stroke(Color.red.opacity(0.95 - Double(i) * 0.12), lineWidth: 2)
          .frame(width: 72 + CGFloat(i + 1) * 22,
                 height: 72 + CGFloat(i + 1) * 22)
          .scaleEffect(pulseScale)
          .opacity(pulseOpacity)
      }
      
      // Button
      Circle()
        .fill(Color.red)
        .frame(width: 72, height: 72)
        .shadow(color: Color.red.opacity(0.55), radius: 14, y: 5)
        .overlay(
          RoundedRectangle(cornerRadius: isRecording ? 5 : 36)
            .fill(.white)
            .frame(width: isRecording ? 25 : 32, height: isRecording ? 25 : 32)
            .animation(.spring(response: 0.35, dampingFraction: 0.65), value: isRecording)
        )
        .onTapGesture { toggle() }
    }
    .onChange(of: isRecording) { _, recording in
      if recording {
        withAnimation(.easeOut(duration: 1.1).repeatForever(autoreverses: false)) {
          pulseScale   = 3.65
          pulseOpacity = 0
        }
      } else {
        withAnimation(.spring()) {
          pulseScale   = 1.0
          pulseOpacity = 0.6
        }
      }
    }
  }
  
  private func toggle() {
    isRecording.toggle()
  }
}

#Preview {
  AnimationView()
    .frame(maxWidth: .infinity, maxHeight: .infinity)
    .background(Color.black)
}