iOS via browser

This example demonstrates how to implement Kryptonim in your iOS app using a browser (SafariViewController). The documentation covers both SwiftUI and UIKit, though the demo app is in SwiftUI. For integrating Kryptonim using the SDK (recommended), check here: iOS.

Steps

1. Create URL with desired parameters and pass it to SafariViewController.

2. Show SafariViewController.

3. Optionally handle callback.

Details

Build URL

You need to build a URL with the desired parameters for the transaction. Users won’t need to manually enter this information during the purchasing process, such as wallet address or fiat currency amount. All parameters can be found here (Query parameters)

struct Configuration {
  var url: String
  var amount: String?
  var currency: String?

  func buildUrlWithParameters() -> URL {
    var urlComponents = URLComponents(string: url)!

    var queryItems: [URLQueryItem] = []
    queryItems.appendIfNotNil(buildQueryItem(name: "amount", value: amount))
    queryItems.appendIfNotNil(buildQueryItem(name: "currency", value: currency))
    if !queryItems.isEmpty { urlComponents.queryItems = queryItems }

    return urlComponents.url!
  }

  private func buildQueryItem(name: String, value: String?) -> URLQueryItem? {
    guard let value = value else { return nil }
    return .init(name: name, value: value)
  }
}

extension Array {
  mutating func appendIfNotNil(_ element: Element?) {
    if let element = element {
      self.append(element)
    }
  }
}

Open SafariViewController

Next, you need to show SFSafariViewController to user.

SwiftUI

struct DemoView: View {
  @State private var showSafari = false

  var body: some View {
    Button {
      self.showSafari = true
    } label: {
      Text("Open Kryptonim")
    }
    .fullScreenCover(isPresented: $showSafari) {
      SafariView(url: buildKryptonimUrl())
    }
  }

  private func buildKryptonimUrl() -> URL {
    var configuration = Kryptonim.Configuration(url: "https://intg.kryptonim.com/redirect-form")
    configuration.amount = "0.5"
    configuration.currency = "USDC"
    return configuration.buildUrlWithParameters()
  }

UIKit

class ViewController: UIViewController {
  private let button = UIButton()

    override func viewDidLoad() {
      super.viewDidLoad()

      button.setTitle("Open Kryptonim", for: .normal)
      button.addTarget(self, action: #selector(openKryptonim), for: .touchUpInside)
      button.translatesAutoresizingMaskIntoConstraints = false
      view.addSubview(button)

      NSLayoutConstraint.activate([
        button.centerXAnchor.constraint(equalTo: view.centerXAnchor),
        button.centerYAnchor.constraint(equalTo: view.centerYAnchor)
      ])
    }

    private func openKryptonim() {
      var configuration = Configuration(url: "https://intg.kryptonim.com/redirect-form")
      configuration.amount = "0.5"
      configuration.currency = "USDC"

      let url = configuration.buildUrlWithParameters()
      let safariVC = SFSafariViewController(url: url)
      present(safariVC, animated: true)
  }
}

Handle callback

If you want to take action after the purchase is finished (either success or failure), you can use the successUrl and failureUrl parameters when building the URL. You need to construct these URL parameters using your app’s URL scheme (details below). Kryptonim will call this URL after the purchase, and you will need to handle it in your app.

Register URL scheme Add your app’s URL scheme to Info.plist. In the code snippet below, we use kryptonim-demo as the URL scheme, so your successUrl and failureUrl parameters should start with kryptonim-demo://. In the examples below, we use kryptonim-demo://kryptonim.purchase.success and kryptonim-demo://kryptonim.purchase.failure.

<key>CFBundleURLTypes</key>
<array>
  <dict>
  <key>CFBundleTypeRole</key>
  <string>Editor</string>
  <key>CFBundleURLSchemes</key>
  <array>
    <string>kryptonim-demo</string>
  </array>
  </dict>
</array>

Handle URL open

SwiftUI

You can handle this in the App file using .onOpenURL method and, for example, using NotificationCenter. When Kryptonim tries to open URL defined in the successUrl or failureUrl parameters, notification will be sent.

@main
struct Kryptonim_DemoApp: App {
  var body: some Scene {
    WindowGroup {
      DemoView()
        .onOpenURL { url in
          Kryptonim.sendNotification(url: url)
        }
    }
  }
}

struct Kryptonim {
  static let notification = Notification.Name(rawValue: "kryptonim.result")

  static func sendNotification(url: URL) {
    if
      let components = URLComponents(url: url, resolvingAgainstBaseURL: false),
      components.scheme == "kryptonim-demo"
    {
      let notification = Notification(name: Kryptonim.notification, object: url, userInfo: nil)
      NotificationCenter.default.post(notification)
    }
  }
}

Then, you can listen to this notification where you want to take action. For example, in the view that showed SFSafariViewController using .onReceive.

.onReceive(NotificationCenter.default.publisher(for: Kryptonim.notification)) { notification in
  guard let url = notification.object as? URL else { return }
  let urlString = url.absoluteString
  if urlString == "kryptonim-demo://kryptonim.purchase.success" {
    print("SUCCESS")
  } else if urlString == "kryptonim-demo://kryptonim.purchase.failure" {
    print("FAILURE")
  }
}

UIKit

You should handle it in SceneDelegate - func scene(_:, openURLContexts:)

func scene(_ scene: UIScene, openURLContexts URLContexts: Set<UIOpenURLContext>) {
  guard let url = URLContexts.first?.url else { return }
  Kryptonim.sendNotification(url: url)
}

Then, you can listen to this notification where you want to take action.

NotificationCenter.default.addObserver(forName: rampNotificationName, object: nil, queue: .main) { notification in
  guard let url = notification.object as? URL else { return }
  let urlString = url.absoluteString
  if urlString == "kryptonim-demo://kryptonim.purchase.success" {
    print("SUCCESS")
  } else if urlString == "kryptonim-demo://kryptonim.purchase.failure" {
    print("FAILURE")
  }
}