SwiftUI redraw test

redraw.swift

import SwiftUI

struct ContentView: View {
    @State private var count = 0
    @State private var states: [InfoView.State] = [.init(text: "", text2: "", text3: "")]

    var body: some View {
        VStack {
            RedrawBorder {
                Button {
                    count += 1
                    if count > 10 {
                        let i = Int.random(in: 0..<states.count)
                        states[i].text = "\(count)"
                        states[i].text2 = "updated"
                    } else {
                        states.append(.init(text: "\(count)", text2: "foo", text3: "bar"))
                    }
                } label: {
                    RedrawBorder {
                        AnimatedText(text: "Push \(count)")
                    }
                }
            }
            List(states) {
                InfoView(state: $0)
            }
        }
        .padding()
    }
}

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

struct RedrawBorder<Content>: View where Content: View {
    @State private var color: Color = .red
    private let content: () -> Content

    init(@ViewBuilder content: @escaping () -> Content) {
        self.content = content
    }

    var body: some View {
        ZStack {
            Rectangle()
                .onAppear(perform: {
                    withAnimation(.linear(duration: 0.5), {
                        color = .clear
                    })
                })
                .foregroundColor(.clear)
                .border(color, width: 5.0)
                .ignoresSafeArea()
            content()
        }
    }
}

struct AnimatedText: View {
    @State private var color: Color = .red
    let text: String

    var body: some View {
        Text(text)
            .onAppear(perform: {
                withAnimation(.linear(duration: 0.5), {
                    color = .clear
                })
            })
            .border(color, width: 5.0)
    }
}

struct InfoView: View {
    struct State: Identifiable {
        let id = UUID()
        var text: String
        var text2: String
        var text3: String
    }

    let state: State

    var body: some View {
        let _ = print("InfoView.body")
        VStack {
            AnimatedText(text: state.text)
            AnimatedText(text: state.text2)
            AnimatedText(text: state.text3)
        }
    }
}