SwiftUI:更改动画进度条(或一般的形状绘图)的开始位置

import SwiftUI

struct ContentView: View {
    @State private var progress: CGFloat = 0.0
    
    var body: some View {
        VStack {
            ProgressBar(progress: progress)
                .frame(width: 200, height: 20)
                .padding()
                .animation(.linear(duration: 2.0))
                .onAppear {
                    self.progress = 1.0
                }
            
            Button("Reset") {
                self.progress = 0.0
            }
            .padding()
        }
    }
}

struct ProgressBar: View {
    var progress: CGFloat
    
    var body: some View {
        GeometryReader { geometry in
            ZStack(alignment: .leading) {
                Rectangle()
                    .frame(width: geometry.size.width, height: geometry.size.height)
                    .opacity(0.3)
                    .foregroundColor(Color.gray)
                
                Rectangle()
                    .frame(width: geometry.size.width * self.progress, height: geometry.size.height)
                    .foregroundColor(Color.blue)
            }
        }
    }
}

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