iOS SDK guide

import YandexPaySDK

class ViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()

        // Check that the SDK is initialized
        guard YandexPaySDKApi.isInitialized else {
          assertionFailure("YandexPaySDK is not initialized.")
          return
        }

        // Specify the theme for the button
        let theme: YandexPayButtonTheme
        if #available(iOS 13.0, *) {
            // Using the `dynamic` parameter, you can specify whether the button needs
            // to change its color palette when the system theme changes
            theme = YandexPayButtonTheme(appearance: .dark, dynamic: true)
        } else {
            theme = YandexPayButtonTheme(appearance: .dark)
        }

        // Initialize the configuration
        let configuration = YandexPayButtonConfiguration(theme: theme)

        // Create the button
        let button = YandexPaySDKApi.instance.createCheckoutButton(configuration: configuration, delegate: self)

        // Specify the corner radius for the button (the default value is 8px)
        button.layer.cornerRadius = .zero

        // Add the button to the hierarchy
        view.addSubview(button)

        // Add the layout for the button
        button.translatesAutoresizingMaskIntoConstraints = false
        NSLayoutConstraint.activate([
            button.centerXAnchor.constraint(equalTo: view.centerXAnchor),
            button.centerYAnchor.constraint(equalTo: view.centerYAnchor),
            button.widthAnchor.constraint(equalToConstant: 250)
        ])
    }
}

import YandexPaySDK

extension ViewController: YandexPayCheckoutButtonDelegate {

    // Process the checkout result
    func yandexPayCheckoutButton(_ button: YandexPayButton, didCompletePaymentWithResult result: YPCheckoutResult) {
        switch result {
        case .succeeded(let checkoutInfo):
            // The checkout was successful
        case .failed(let checkoutError):
            // There was an error during checkout
        case .cancelled:
            // The user closed/swiped the YandexPay form
        }
    }

    // Provide UIViewController from which you need to show the YandexPay form by clicking a button
    func yandexPayCheckoutButtonDidRequestViewControllerForPresentation(_ button: YandexPayButton) -> UIViewController? {
        return self
    }

    // Provide information about the order
    func yandexPayCheckoutButtonDidRequestPaymentSheet(_ button: YandexPayButton) -> YPCheckoutPaymentSheet? {
        return YPCheckoutPaymentSheet(
            // Currency code
            currencyCode: .rub,
            // information about the user cart
            cart: YPPaymentCart(items: [
                YPProduct(id: "1", total: "434.39", quantity: YPQuantity(count: "1")),
                YPProduct(id: "2", total: "1474.86", quantity: YPQuantity(count: "2")),
            ]),
            orderId: nil,
            metadata: nil
        )
    }
}

import YandexPaySDK

// In this example, we use a delegate object to report events
// from the UIViewController container written in Objective-C.
// To make this protocol available in Objective-C, we label it using the @objc
// attribute.
@objc
protocol YandexPayCheckoutButtonContainerDelegate: AnyObject {
    // We will use this method to notify  
    // that the checkout token was received successfully.
    func yandexPayCheckoutButtonDidSucceedWithOrderId(_ orderId: String)

    // we will use this method to report an error
    // that arose in the process.
    func yandexPayCheckoutButtonDidFail()

    // We'll use this method to notify about cancellation.
    func yandexPayCheckoutButtonDidCancel()

    // We'll use this method to get UIViewController
    // of the object for which you need to show the Yandex Pay form.
    func yandexPayCheckoutButtonDidRequestViewController() -> UIViewController?

    // In the example, we'll use a separate method to get
    // information about user cart. The CardProduct model is written
    // in Objective-C and we use it here because it's header file
    // has been added to the bridging header file of the project.
    func yandexPayCheckoutButtonDidRequestCardProducts() -> [CardProduct]
}

// A layer object that will include the Yandex Pay button
// and interact with the button and with the Objective-C code.
final class YandexPayCheckoutButtonContainer: UIView {

    // We label the properties that should be available from Objective-C
    // with the @objc attribute.
    @objc
    weak var delegate: YandexPayCheckoutButtonContainerDelegate?

    private var payButton: YandexPayButton!

    override init(frame: CGRect) {
        super.init(frame: frame)
        setupView()
    }

    required init?(coder: NSCoder) {
        super.init(coder: coder)
        setupView()
    }

    // This container only includes a button, so let's override
    // intrinsicContentSize. If your container is more sophisticated,
    // you can use any view layout for it at your discretion.
    override var intrinsicContentSize: CGSize {
        return payButton.intrinsicContentSize
    }

    private func setupView() {
        // Check whether the SDK has been initialized.
        guard YandexPaySDKApi.isInitialized else {
            assertionFailure("YandexPaySDKApi is not initialized.")
            return
        }

        // Specify a theme for the button.
        let payButtonTheme = YandexPayButtonTheme(appearance: .dark, dynamic: true)

        // Specify the button layout.
        let payButtonConfiguration = YandexPayButtonConfiguration(theme: payButtonTheme)

        // Create a button using YandexPaySDKApi.
        payButton = YandexPaySDKApi.instance.createCheckoutButton(configuration: payButtonConfiguration, delegate: self)

        // Add the button to the hierarchy.
        payButton.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        payButton.frame = bounds
        addSubview(payButton)
    }
}

// Implement the button's delegate to get events from it.
extension YandexPayCheckoutButtonContainer: YandexPayCheckoutButtonDelegate {
    func yandexPayCheckoutButton(_ button: YandexPayButton, didCompletePaymentWithResult result: YPCheckoutResult) {
        // Get events about a successfully received token or an error.
        switch result {
        case .succeeded(let checkoutInfo):
            // Use the delegate object to notify the Objective-C code that the token was received.
            // payment token
            delegate?.yandexPayCheckoutButtonDidSucceedWithOrderId(checkoutInfo.orderId)
        case .failed:
            // Use the delegate object to report the error to the Objective-C code.
            delegate?.yandexPayCheckoutButtonDidFail()
        case .cancelled:
            // Use the delegate object to notify the Objective-C code about a cancellation.
            delegate?.yandexPayCheckoutButtonDidCancel()
        @unknown default:
            break
        }
    }

    func yandexPayCheckoutButtonDidRequestViewControllerForPresentation(_ button: YandexPayButton) -> UIViewController? {
        // Use the delegate object to request, from the Objective-C code, the UIViewController
        // object in which the Yandex Pay form should be shown.
        return delegate?.yandexPayCheckoutButtonDidRequestViewController()
    }

    func yandexPayCheckoutButtonDidRequestPaymentSheet(_ button: YandexPayButton) -> YPCheckoutPaymentSheet? {
        guard let delegate = delegate else {
            assertionFailure("Delegate is missing.")
            return nil
        }

        // Construct the YPCheckoutPaymentSheet object here and return it to
        // the button. Naturally, when creating the YPCheckoutPaymentSheet object,
        // you need to use a certain business logic written in
        // Objective-C. To interact with this business logic,
        // you can use the same delegate object
        // or other Objective-C
        // classes (for example, some services or interactors)
        // that encapsulate this logic. To do this,
        // make these classes available in Swift by adding their
        // header files to the bridging header file of your project.
        // Note that if you implement your business logic in
        // Objective-C, it will use models implemented in
        // Objective-C. That's why here you can implement their mapping
        // to YandexPaySDK models.

        // In this example, we use a delegate object.
        let products = delegate.yandexPayCheckoutButtonDidRequestCardProducts()

        // Construct YPCheckoutPaymentSheet
        return YPCheckoutPaymentSheet(
            currencyCode: .rub,
            cart: YPPaymentCart(items: products.map {
                YPProduct(id: $0.productID, total: $0.total, quantity: YPQuantity(count: $0.quantity))
            }),
            orderId: nil,
            metadata: nil
        )
    }
}

#import <YandexPaySDK/YandexPaySDK-Swift.h>

// Add conformance to the protocol.
@interface ViewController (ViewControllerYandexPayButtonContainer) <YandexPayCheckoutButtonContainerDelegate>

@end

// Declare private methods.
@interface ViewController ()

- (void)showAlertWithMessage:(NSString *)message;

@end

// Implement the ViewController class.
@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    self.view.backgroundColor = [UIColor systemBackgroundColor];

    // Use the layer object to show the Yandex Pay button.
    YandexPayCheckoutButtonContainer *container = [[YandexPayCheckoutButtonContainer alloc] init];

    // Specify the delegate object for the layer.
    container.delegate = self;

    // Add the layer object to the hierarchy.
    container.translatesAutoresizingMaskIntoConstraints = false;
    [self.view addSubview:container];
    [[container.centerXAnchor constraintEqualToAnchor:self.view.centerXAnchor] setActive:TRUE];
    [[container.centerYAnchor constraintEqualToAnchor:self.view.centerYAnchor] setActive:TRUE];
}

- (void)showAlertWithMessage:(NSString *)message {
    UIAlertController *controller = [UIAlertController alertControllerWithTitle:@"Message" message:message preferredStyle:UIAlertControllerStyleAlert];
    [controller addAction:[UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:nil]];
    [self presentViewController:controller animated:TRUE completion:nil];
}

- (void)yandexPayCheckoutButtonDidSucceedWithOrderId:(NSString *)orderId {
    // We've got a token and can now check out
    // using this token.
    [self showAlertWithMessage:[NSString stringWithFormat:@"Checkout complete: %@", orderId]];

    // Access the payment gateway
    // ...
}

- (void)yandexPayCheckoutButtonDidFail {
    // We received an error event.
    [self showAlertWithMessage:@"Checkout failed"];
}

- (void)yandexPayCheckoutButtonDidCancel {
    // We received a cancellation event.
    [self showAlertWithMessage:@"Checkout was cancelled by the user"];
}

- (UIViewController *)yandexPayCheckoutButtonDidRequestViewController {
    // Return the current UIViewController to render the form.
    return self;
}

- (NSArray<CardProduct *> *)yandexPayCheckoutButtonDidRequestCardProducts {
    // If needed, transmit the order data and other
    // data using the delegate or by any other convenient method.
    NSMutableArray *products = [[NSMutableArray alloc] init];
    [items addObject:[[CardProduct alloc] initWithProductID:@"ID-1" total:@"1000.00" quantity: @"1"]];
    [items addObject:[[CardProduct alloc] initWithProductID:@"ID-2" total:@"500.00" quantity: @"2"]];
    return products;
}

@end

@interface Product : NSObject

@property (readonly, copy, nonatomic) NSString *productID;
@property (readonly, copy, nonatomic) NSString *total;
@property (readonly, copy, nonatomic) NSString *quantity;

- (instancetype)initWithProductID:(NSString *)productID
                            total:(NSString *)total
                         quantity:(NSString *)quantity;

@end