SwiftUI: Wallet Card Transition

ContentView.swift

import SwiftUI

struct Card: Identifiable, Hashable {
    let id = UUID()
    let creditID = UUID()
    let colors: [Color]
    let name: String
    let number: String
}

struct Expense: Identifiable, Hashable {
    let id = UUID()
    let image: String
    let name: String
    let category: String
    let amount: String
    let date: String
}

struct ContentView: View {
    var cards: [Card]
    @Namespace var namespace
    @State var selected: Card?

    var body: some View {
        if let selected {
            DetailContentView(card: selected, namespace: namespace) {
                withAnimation {
                    self.selected = nil
                }
            }
        } else {
            ScrollView {
                LazyVStack(spacing: 12) {
                    ForEach(cards) { data in
                        CardView(card: data)
                            .matchedGeometryEffect(id: data, in: namespace)
                            .onTapGesture {
                                withAnimation {
                                    self.selected = data
                                }
                            }
                    }
                }
            }
            .scrollIndicators(.hidden)
        }
    }
}

struct DetailContentView: View {
    @State var show = false
    let card: Card
    let namespace: Namespace.ID
    let onTap: () -> Void

    var body: some View {
        VStack(spacing: 12) {
            CardView(card: card)
                .matchedGeometryEffect(id: card, in: namespace)
                .onTapGesture(perform: onTap)
                .zIndex(1)
            ExpenseView()
                .zIndex(0)
        }
        .offset(y: show ? 0 : 400)
        .onAppear {
            withAnimation {
                show = true
            }
        }
        .id(card)
    }
}

struct CardView: View {
    var card: Card

    var body: some View {
        HStack {
            VStack(alignment: .leading, spacing: 26) {
                Spacer()
                Spacer()
                Text(card.name).fontWeight(.semibold)
                Text(card.number)
            }
            .font(.title3)
            Spacer()
        }
        .padding(24)
        .foregroundStyle(.white)
        .frame(maxWidth: .infinity)
        .frame(height: 200)
        .background(
            LinearGradient(
                colors: card.colors,
                startPoint: .topLeading,
                endPoint: .bottomTrailing
            ),
            in: .rect(cornerRadius: 24)
        )
        .padding(.horizontal, 20)
    }
}

struct ExpenseView: View {
    private let expenses: [Expense] = .samples
    @State private var show: Bool = false

    var body: some View {
        ScrollView {
            LazyVStack {
                ForEach(expenses.indices, id: \.self) { index in
                    let item = expenses[index]
                    HStack(spacing: 16) {
                        Circle()
                            .foregroundStyle(.sampleLinearGradient)
                            .frame(width: 40)
                        VStack(alignment: .leading) {
                            Text(item.name)
                                .font(.headline)
                            Text(item.category)
                                .foregroundStyle(.secondary)
                        }
                        Spacer()
                        VStack(alignment: .trailing) {
                            Text(item.amount)
                                .font(.headline)
                            Text(item.date)
                                .foregroundStyle(.secondary)
                        }
                    }
                    .foregroundStyle(.black)
                    .offset(y: show ? 0 : CGFloat(index * 100))
                    .opacity(show ? 1 : 0)
                    .animation(.spring(duration: Double(index) * 0.15), value: show)
                    .padding()
                }
            }
            .padding(10)
        }
        .scrollIndicators(.hidden)
        .background(.white, in: .rect(cornerRadius: 24))
        .frame(maxHeight: .infinity)
        .ignoresSafeArea()
        .padding(.horizontal, 20)
        .onAppear {
            withAnimation {
                show = true
            }
        }
        .onDisappear {
            withAnimation {
                show = false
            }
        }
    }
}

#Preview("ContentView") {
    ContentView(cards: .samples)
}

extension ShapeStyle where Self == LinearGradient {
    static var sampleLinearGradient: Self {
        let colors: [[Color]] = [
            [.orange, .pink],
            [.mint, .green],
            [.cyan, .blue],
            [.purple, .pink],
        ]
        return LinearGradient(
            colors: colors.randomElement()!,
            startPoint: .top,
            endPoint: .bottom
        )
    }
}

extension [Card] {
    static let samples: Self = [
        Card(colors: [.orange, .pink], name: "TAKEHITO KOSHIMIZU", number: "000 000 000 0001"),
        Card(colors: [.mint, .green], name: "TAKEHITO KOSHIMIZU", number: "000 000 000 0002"),
        Card(colors: [.cyan, .blue], name: "TAKEHITO KOSHIMIZU", number: "000 000 000 0003"),
        Card(colors: [.purple, .pink], name: "TAKEHITO KOSHIMIZU", number: "000 000 000 0004"),
    ]
}

extension [Expense] {
    static let samples: Self = [
        Expense(image: "amazon", name: "Amazon", category: "Groceries", amount: "$128", date: "20/03/2024"),
        Expense(image: "dribbble", name: "Dribbble", category: "Membership", amount: "$30", date: "20/03/2024"),
        Expense(image: "apple", name: "Apple", category: "Apple Pay", amount: "$28", date: "20/03/2024"),
        Expense(image: "instagram", name: "Instagram", category: "Ad Publish", amount: "$100", date: "20/03/2024"),
        Expense(image: "netflix", name: "Netflix", category: "Movies", amount: "$55", date: "20/03/2024"),
        Expense(image: "photoshop", name: "Photoshop", category: "Service", amount: "$348", date: "20/03/2024")
    ]
}