要显示图像，音频和视频等媒体内容，您需要在iOS应用中添加NotificationServiceExtension。对于要执行的iOS应用程序中的NotificationServiceExtension，您需要将可变内容值发送为1，这在您提到的有效负载中看起来很好。
在NotificationServiceExtension中，您将在大约10秒内从通知有效负载中发送的URL下载映像。下载图像后，您需要将图像保存在FileManager中。之后，使用文件图像URL初始化UNNotificationAttachment并将其传递给完成处理程序。 PFA代码如下
import UserNotifications</code>
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 {
// Modify the notification content here…
var urlString:String? = nil
if let urlImageString = request.content.userInfo[“urlImageString”] as? String {
urlString = urlImageString
}
if urlString != nil, let fileUrl = URL(string: urlString!) {
print("fileUrl: \(fileUrl)")
guard let imageData = NSData(contentsOf: fileUrl) else {
contentHandler(bestAttemptContent)
return
}
guard let attachment = UNNotificationAttachment.saveImageToDisk(fileIdentifier: "image.jpg", data: imageData, options: nil) else {
print("error in UNNotificationAttachment.saveImageToDisk()")
contentHandler(bestAttemptContent)
return
}
bestAttemptContent.attachments = [ attachment ]
}
contentHandler(bestAttemptContent)
}
}
override func serviceExtensionTimeWillExpire() {
// Called just before the extension will be terminated by the system.
// Use this as an opportunity to deliver your “best attempt” at modified content, otherwise the original push payload will be used.
if let contentHandler = contentHandler, let bestAttemptContent = bestAttemptContent {
contentHandler(bestAttemptContent)
}
}
</code>
}
@available（iOSApplicationExtension 10.0，*）
扩展名UNNotificationAttachment {
static func saveImageToDisk(fileIdentifier: String, data: NSData, options: [NSObject : AnyObject]?) -> UNNotificationAttachment? {
let fileManager = FileManager.default
let folderName = ProcessInfo.processInfo.globallyUniqueString
let folderURL = NSURL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent(folderName, isDirectory: true)do {
try fileManager.createDirectory(at: folderURL!, withIntermediateDirectories: true, attributes: nil)
let fileURL = folderURL?.appendingPathComponent(fileIdentifier)
try data.write(to: fileURL!, options: [])
let attachment = try UNNotificationAttachment(identifier: fileIdentifier, url: fileURL!, options: options)
return attachment
} catch let error {
print("error \(error)")
}
return nil
}
</code>
}