SwiftUI Custom Button Implementation

ContentView.swift

//
//  ContentView.swift
//  GoGoButtons
//
//  Created by Allen Humphreys on 10/31/22.
//

import SwiftUI

extension Color {
    init(hex: String) {
        let hex = hex.trimmingCharacters(in: CharacterSet.alphanumerics.inverted)
        var int: UInt64 = 0
        Scanner(string: hex).scanHexInt64(&int)
        let a, r, g, b: UInt64
        switch hex.count {
        case 3: // RGB (12-bit)
            (a, r, g, b) = (255, (int >> 8) * 17, (int >> 4 & 0xF) * 17, (int & 0xF) * 17)
        case 6: // RGB (24-bit)
            (a, r, g, b) = (255, int >> 16, int >> 8 & 0xFF, int & 0xFF)
        case 8: // ARGB (32-bit)
            (a, r, g, b) = (int >> 24, int >> 16 & 0xFF, int >> 8 & 0xFF, int & 0xFF)
        default:
            (a, r, g, b) = (1, 1, 1, 0)
        }

        self.init(
            .sRGB,
            red: Double(r) / 255,
            green: Double(g) / 255,
            blue:  Double(b) / 255,
            opacity: Double(a) / 255
        )
    }
}

extension Color {
    static var CustomButtonText: Color {
        // #2F7185
        Color(hex: "#2F7185")
    }

    static var CustomButtonBackground: Color {
        // #2F7185
        Color(hex: "#f5f5f5")
    }
}

class CustomColor: UIColor {
    override func resolvedColor(with traitCollection: UITraitCollection) -> UIColor {
        if traitCollection.activeAppearance == .active {
            return self
        } else {
            return .red
        }
    }
}

struct CustomButton: View {
    let configuration: ButtonStyle.Configuration
    @Environment(\.isEnabled) private var isEnabled: Bool
    @Environment(\.scenePhase) var scenePhase
    @Environment(\.isPresented) var isPresented: Bool
    @Environment(\.isFocused) var isFocused: Bool

    var body: some View {
        configuration.label
            .padding()
            .background(Color.CustomButtonBackground)
            .foregroundColor(.CustomButtonText)
            .background(in: Capsule())
            .animation(.easeOut(duration: 0.2), value: configuration.isPressed)
            .onChange(of: isEnabled, perform: { newValue in
                print("isEnabled: \(newValue)")
            })
            .onChange(of: scenePhase) { newValue in
                //nothing
                print("Phase: \(newValue)")
            }
            .onChange(of: isPresented) { newValue in
                print("isPresented: \(newValue)")
            }
            .onChange(of: isFocused) { newValue in
                print("isFocused: \(newValue)")
            }
    }
}

struct CustomButtonConfiguration: ButtonStyle {
    func makeBody(configuration: Configuration) -> some View {
        CustomButton(configuration: configuration)
    }
}

struct ContentView: View {
    @State
    var alert: String = ""
    @State
    private var alertShowing = false

    var body: some View {
        VStack(alignment: .leading) {
            Button("Bordered") {
                alert = "Bordered"
                alertShowing = true
            }
                .buttonStyle(.bordered)
                .padding([.top, .bottom])

            Button("Bordered Prominent") {
                alert = "Bordered Prominent"
                alertShowing = true
            }
                .buttonStyle(.borderedProminent)
                .padding([.top, .bottom])

            Button("Borderless") {
                alert = "Borderless"
                alertShowing = true
            }
                .buttonStyle(.borderless)
                .padding([.top, .bottom])

            Button("Plain") {
                alert = "Plain"
                alertShowing = true
            }
                .buttonStyle(.plain)
                .padding([.top, .bottom])

            Button("Custom Button") {
                alert = "Custom"
                alertShowing = true
            }
                .padding([.top, .bottom])
                .buttonStyle(CustomButtonConfiguration())
        }
        .alert(isPresented: $alertShowing, content: {
            Alert(
                title: Text(alert),
                dismissButton: .default(Text("OK"))
            )
        })
    }
}

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