I'm developing a ticket app with Host card emulation. The session starts correctly the first time, but when trying to emulate a second ticket, after the first one has been read by the reader, or after the emulation has been canceled by the user, it doesn't work correctly for a while.
This is my CardSessionManager:
import CoreNFC
@available(iOS 17.4, *)
class CardSessionManager {
private static var cardSession: CardSession? = nil
private static var presentmentIntent: NFCPresentmentIntentAssertion? = nil
static func initCardSession(_ accessCode: String) {
cardSession?.invalidate()
cardSession = nil
let ProcessAPDU: (_: Data) -> Data = { capdu in
var response = Data(accessCode.utf8)
response.append(0x90)
response.append(0x00)
return response
}
Task {
guard NFCReaderSession.readingAvailable,
CardSession.isSupported,
await CardSession.isEligible else {
return
}
do {
presentmentIntent = try await NFCPresentmentIntentAssertion.acquire()
cardSession = try await CardSession()
} catch {
return
}
if let cardSession {
for try await event in cardSession.eventStream {
switch event {
case .sessionStarted:
cardSession.alertMessage = String(localized: "Searching reader...")
try await cardSession.startEmulation()
case .readerDetected:
cardSession.alertMessage = String(localized: "Reading...")
case .readerDeselected:
cardSession.alertMessage = String(localized: "Successful reading!")
await cardSession.stopEmulation(status: .success)
case .received(let cardAPDU):
cardSession.alertMessage = String(localized: "Communicating with reader.")
do {
try await cardAPDU.respond(response: ProcessAPDU(cardAPDU.payload))
} catch {
cardSession.alertMessage = error.localizedDescription
}
case .sessionInvalidated(reason: _):
cardSession.alertMessage = String(localized: "Ending communication with reader.")
presentmentIntent = nil
@unknown default:
break
}
}
}
}
}
}
Topic:
App & System Services
SubTopic:
Hardware