Notification extensions

npx create-target notification-content

import UserNotifications
import UserNotificationsUI

class NotificationViewController: UIViewController, UNNotificationContentExtension {
    
    @IBOutlet var label: UILabel?
    
    func didReceive(_ notification: UNNotification) {
        // Extract data from notification
        let content = notification.request.content
        label?.text = content.body
        
        // Access custom payload
        if let customData = content.userInfo["customData"] as? String {
            // Use custom data
        }
    }
    
    // Handle notification actions
    func didReceive(_ response: UNNotificationResponse, completionHandler completion: @escaping (UNNotificationContentExtensionResponseOption) -> Void) {
        if response.actionIdentifier == "LIKE_ACTION" {
            // Handle like action
            completion(.dismissAndForwardAction)
        } else {
            completion(.dismiss)
        }
    }
}

<key>NSExtension</key>
<dict>
  <key>NSExtensionAttributes</key>
  <dict>
    <key>UNNotificationExtensionCategory</key>
    <string>myNotificationCategory</string>
    <key>UNNotificationExtensionInitialContentSizeRatio</key>
    <real>1.0</real>
  </dict>
</dict>

{
  "aps": {
    "alert": "New message",
    "category": "myNotificationCategory"
  },
  "customData": "value"
}

npx create-target notification-service

import UserNotifications

class NotificationService: UNNotificationServiceExtension {
    
    var contentHandler: ((UNNotificationContent) -> Void)?
    var bestAttemptContent: UNMutableNotificationContent?
    
    override func didReceive(_ request: UNNotificationRequest, withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void) {
        self.contentHandler = contentHandler
        bestAttemptContent = (request.content.mutableCopy() as? UNMutableNotificationContent)
        
        if let bestAttemptContent = bestAttemptContent {
            // Download and attach an image
            if let imageURLString = request.content.userInfo["image_url"] as? String,
               let imageURL = URL(string: imageURLString),
               let imageData = try? Data(contentsOf: imageURL),
               let attachment = self.createAttachment(data: imageData, identifier: "image") {
                bestAttemptContent.attachments = [attachment]
            }
            
            // Decrypt content if needed
            if let encryptedBody = request.content.userInfo["encrypted_body"] as? String {
                bestAttemptContent.body = decrypt(encryptedBody)
            }
            
            contentHandler(bestAttemptContent)
        }
    }
    
    override func serviceExtensionTimeWillExpire() {
        // Called when extension is about to be terminated
        // Deliver the best attempt content
        if let contentHandler = contentHandler, let bestAttemptContent = bestAttemptContent {
            contentHandler(bestAttemptContent)
        }
    }
    
    private func createAttachment(data: Data, identifier: String) -> UNNotificationAttachment? {
        let fileManager = FileManager.default
        let tmpSubFolderName = ProcessInfo.processInfo.globallyUniqueString
        let tmpSubFolderURL = URL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent(tmpSubFolderName, isDirectory: true)
        
        do {
            try fileManager.createDirectory(at: tmpSubFolderURL, withIntermediateDirectories: true, attributes: nil)
            let fileURL = tmpSubFolderURL.appendingPathComponent(identifier)
            try data.write(to: fileURL)
            let attachment = try UNNotificationAttachment(identifier: identifier, url: fileURL, options: nil)
            return attachment
        } catch {
            print("Error creating attachment: \(error)")
        }
        
        return nil
    }
    
    private func decrypt(_ encrypted: String) -> String {
        // Implement your decryption logic
        return encrypted
    }
}

{
  "aps": {
    "alert": "Check out this photo!",
    "mutable-content": 1
  },
  "image_url": "https://example.com/photo.jpg"
}

import UserNotifications

func registerNotificationActions() {
    let likeAction = UNNotificationAction(
        identifier: "LIKE_ACTION",
        title: "Like",
        options: [.foreground]
    )
    
    let commentAction = UNNotificationAction(
        identifier: "COMMENT_ACTION",
        title: "Comment",
        options: [.foreground]
    )
    
    let category = UNNotificationCategory(
        identifier: "myNotificationCategory",
        actions: [likeAction, commentAction],
        intentIdentifiers: [],
        options: [.customDismissAction]
    )
    
    UNUserNotificationCenter.current().setNotificationCategories([category])
}