Please find below a complete app example.
It has a button, when you press it, a local notification is created. However, the UnNotificationCenter.delegate is called twice, and I can't understand why.
I am trying to move my project from Objective-C to Swift, and my similar code there doesn't get called twice, so I'm confused.
Can anybody shine a light on this? Pointers appreciated.
App:
@main
struct NotifTestApp: App {
init() {
UNUserNotificationCenter.current().delegate = NotificationReceiveHandler.shared
configureUserNotifications()
}
var body: some Scene {
WindowGroup {
ContentView()
}
}
private func configureUserNotifications() {
UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .badge, .sound]) { granted, error in
if granted {
print("Notification permission granted.")
} else if let error = error {
print("Error requesting notification permissions: \(error)")
}
}
}
}
class NotificationReceiveHandler: NSObject, UNUserNotificationCenterDelegate {
static let shared = NotificationReceiveHandler()
//>> THIS IS CALLED TWICE WHEN I PRESS THE BUTTON
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
NSLog(">>> Will present notification!")
completionHandler([.sound])
}
}
///THE UI
struct ContentView: View {
var body: some View {
VStack {
Text("👾")
.imageScale(.large)
.foregroundStyle(.tint)
Text("Notification test!")
Text("When i press the button, will present is called twice!!").font(.footnote)
.padding(10)
Button("Create Notification") {
createNotification(
message: "This is a test notification",
header: "Test Notification",
category: "TEST_CATEGORY",
playSound: true,
dictionary: nil,
imageName: nil)
}
.padding()
.background(Color.blue)
.foregroundColor(.white)
.cornerRadius(8)
}
.padding()
}
}
#Preview {
ContentView()
}
private func createNotification(message: String, header: String, category: String, playSound: Bool = true, dictionary: NSDictionary? = nil, imageName: String? = nil) {
let content = UNMutableNotificationContent()
content.title = header
content.body = message
content.categoryIdentifier = category
content.badge = NSNumber(value: 0)
if let imageName = imageName, let imageURL = Bundle.main.url(forResource: imageName, withExtension: "png") {
do {
let attachment = try UNNotificationAttachment(identifier: "image", url: imageURL, options: nil)
content.attachments = [attachment]
} catch {
print("Error creating notification attachment: \(error)")
}
}
content.sound = playSound ? UNNotificationSound(named: UNNotificationSoundName("event.aiff")) : nil
if let infoDict = dictionary {
content.userInfo = infoDict as! [AnyHashable: Any]
}
let request = UNNotificationRequest(identifier: UUID().uuidString, content: content, trigger: nil)
UNUserNotificationCenter.current().add(request, withCompletionHandler: nil)
}
