NaviteProgressView6.swift

import SwiftUI

struct ContentView: View {
    
    let timer = Timer.publish(every: 0.25, on: .main, in: .default).autoconnect()
    @State private var progress: CGFloat = 0.0
    var total: CGFloat = 1.0
    
    var body: some View {
        ProgressView(value: progress, total: total, label: {
            HStack {
                Button(action: {
                    self.progress -= 0.1
                }, label: {
                    Image(systemName: "sun.min.fill")
                        .resizable()
                        .frame(width: 30, height: 30)
                        .aspectRatio(contentMode: .fit)
                })
                Spacer()
                Button(action: {
                    self.progress += 0.1
                }, label: {
                    Image(systemName: "sun.max.fill")
                        .resizable()
                        .frame(width: 30, height: 30)
                        .aspectRatio(contentMode: .fit)
                })
            }
        })
        .progressViewStyle(CustomLinearProgressViewStyle1(progress: progress, total: total))
        .padding(20)
        .onReceive(timer) { _ in
            if progress < 1 {
                self.progress += 0.1
            } else {
                timer.upstream.connect().cancel()
            }
        }
    }
    
}

struct CustomLinearProgressViewStyle1: ProgressViewStyle {

    var progressColour: Color = .blue
    var successColour: Color = .green
    var progress: CGFloat
    var total: CGFloat
    
    func makeBody(configuration: Configuration) -> some View {
        ProgressView(configuration)
            .foregroundColor(progress >= total ? successColour : progressColour)
            .accentColor(progress >= total ? successColour : progressColour)
            .animation(Animation.linear(duration: 1))
    }
    
}