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Delegates, delegates, DELEGATES!! ​

Always retain custom delegate implementations that you use in a your own custom iOS classes. Not doing so can cause your delegate to get garbage collected early and functionality not working as expected.

For example:

  • BAD
ts
let applePayController: PKPaymentAuthorizationViewController

applePayController =
  PKPaymentAuthorizationViewController.alloc().initWithPaymentRequest(
    paymentRequest
  )
applePayController.delegate =
  PKPaymentAuthorizationViewControllerDelegateImpl.initWithOwner(this)
  • GOOD
ts
let applePayController: PKPaymentAuthorizationViewController
let applePayControllerDelegate: PKPaymentAuthorizationViewControllerDelegateImpl

applePayController =
  PKPaymentAuthorizationViewController.alloc().initWithPaymentRequest(
    paymentRequest
  )
applePayControllerDelegate =
  PKPaymentAuthorizationViewControllerDelegateImpl.initWithOwner(this)
applePayController.delegate = applePayControllerDelegate
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