簡介
在 iOS 10 中新加入 UserNotifications 框架,對以往雜亂無章的通知系統 API 進行了統一,更方便開發者們快速引用。關于新框架的一些基本概念在喵大的《iOS 10 UserNotifications 框架解析》中已有詳細的描述,本文只對實踐中的具體運用做介紹。
基本流程
iOS 10中通知相關操作遵循下面的流程:
權限申請
iOS 各個版本 Notifications 權限申請代碼如下:
// iOS 10 support
if #available(iOS 10.0, *) {
let options: UNAuthorizationOptions = [.alert, .sound, .badge]
UNUserNotificationCenter.current().requestAuthorization(options: options) { granted, error in
if granted {
// 用戶允許進行通知
}
}
}
// iOS 9 support
else if #available(iOS 9, *) {
let types: UIUserNotificationType = [.alert, .sound, .badge]
let settings = UIUserNotificationSettings(types: types, categories: nil)
UIApplication.shared.registerUserNotificationSettings(settings)
// ...其他操作
if UIApplication.shared.currentUserNotificationSettings?.types != [] {
// 用戶允許進行通知
}
}
// iOS 8 support
else if #available(iOS 8, *) {
let types: UIUserNotificationType = [.alert, .sound, .badge]
let settings = UIUserNotificationSettings(types: types, categories: nil)
UIApplication.shared.registerUserNotificationSettings(settings)
// ...其他操作
if UIApplication.shared.currentUserNotificationSettings?.types != [] {
// 用戶允許進行通知
}
}
// iOS 7 support
else {
let types: UIRemoteNotificationType = [.badge, .sound, .alert]
UIApplication.shared.registerForRemoteNotifications(matching: types)
}
注冊Token
當用戶同意授權以后,還需要向系統注冊一個 Device Token,并將這個 token 發送到 APNs(Apple Push Notification Service),然后 APNs 通過 token 識別設備和應用,并通知推送給用戶。
// 向 APNs 請求 token
UIApplication.shared.registerForRemoteNotifications()
// Called when APNs has assigned the device a unique token
func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
let tokenString = deviceToken.reduce("", {$0 + String(format: "%02X", $1)})
print("APNs device token: \(tokenString)")
// 上傳至后臺服務器
}
// Called when APNs failed to register the device for push notifications
func application(_ application: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: Error) {
// Print the error to console (you should alert the user that registration failed)
print("APNs registration failed: \(error)")
}
發送推送通知
關于 APNs 的推送原理 就不做詳細說明,這里以 Node.js 為例子搭建推送測試工具,步驟如下:
1、創建 APNs 服務的訪問 Auth Key ID
2、獲取 Key ID,點擊 Download 同時下載 .p8 證書文件
3、獲取開發者賬號的 Team ID
4、編寫測試腳本 push.js,內容如下:
var apn = require('apn');
if (process.argv.length == 3) {
// Enter the device token
var deviceToken = process.argv[2];
// Set up apn with the APNs Auth Key
var apnProvider = new apn.Provider({
token: {
key: 'xxxx.p8', // Path to the key p8 file
keyId: 'xxxx',
teamId: 'xxxx',
},
production: false // Set to true if sending a notification to a production iOS app
});
// Prepare a new notification
var notification = new apn.Notification();
// Specify your iOS app's Bundle ID (accessible within the project editor)
notification.topic = 'com.domain.xxxx';
// Set expiration to 1 hour from now (in case device is offline)
notification.expiry = Math.floor(Date.now() / 1000) + 3600;
// Set app badge indicator
notification.badge = 1;
// Play ping.aiff sound when the notification is received
notification.sound = 'default';
// Display the following message (the actual notification text, supports emoji)
notification.alert = 'Hello World \u270C';
// Send any extra payload data with the notification which will be accessible to your app in didReceiveRemoteNotification
notification.payload = {id: 123};
// Actually send the notification
apnProvider.send(notification, deviceToken).then(function(result) {
// Check the result for any failed devices
console.log(result);
});
} else {
console.log("Usage: node push.js <deviceToken>");
}
至此就可以測試遠程推送通知了。當然還可以其他類似的工具 NWPusher
node push.js 8c6f8b7056613a5223c690fb171697c524173b9c39e7dff688c66f0b23fbefdb
展示處理
iOS 10以前通知完全是系統行為,開發者無法自主控制,引入 UserNotifications 框架以后通知數據處理流程如下:
其中 Service Extension 和 Content Extension 前者可以讓我們有機會在收到遠程推送的通知后,展示之前對通知內容進行修改;后者可以用來自定義通知視圖UI的樣式。尤其是Service Extension收到通知以后必執行,iOS平臺終于可以做更精準的推送到達率統計了。
1、創建 Service Extension,Xcode 會自動生成模板代碼。在這里可以進行埋點統計,并在通知中展示多媒體文件(圖片/音頻/視頻)。
class NotificationService: UNNotificationServiceExtension {
var contentHandler: ((UNNotificationContent) -> Void)?
var bestAttemptContent: UNMutableNotificationContent?
/**
該方法可以在限定時間內(30秒)修改請求中的 content 內容,然后返回給系統顯示
*/
override func didReceive(_ request: UNNotificationRequest, withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void) {
self.contentHandler = contentHandler
bestAttemptContent = (request.content.mutableCopy() as? UNMutableNotificationContent)
if let bestAttemptContent = bestAttemptContent {
// 進行 Push 到達的埋點統計
var msgid = 1
if let tmp = bestAttemptContent.userInfo["msgid"] as? NSNumber {
msgid = tmp.intValue
}
tracePush(msgId: msgId)
/**
添加多媒體附件
內置資源支持10MB以內圖片,50M以內音視頻
外鏈支持30秒內能下載完成的多媒體文件
*/
if let imageURLString = bestAttemptContent.userInfo["image"] as? String, let URL = URL(string: imageURLString) {
downloadAndSave(url: URL) { localURL in
if let localURL = localURL {
do {
let attachment = try UNNotificationAttachment(identifier: "image_downloaded", url: localURL, options: nil)
bestAttemptContent.attachments = [attachment]
} catch {
print(error)
}
}
contentHandler(bestAttemptContent)
}
} else {
contentHandler(bestAttemptContent)
}
}
}
/**
一定時間內(30秒)沒將內容返回給系統,則會自動調用該方法,未完成的修改將被忽略
*/
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)
}
}
}
2、創建 Content Extension,Xcode 會自動生成模板代碼(若不需要自定義UI,可跳過本部分)。iOS 10中通知分類注冊方式更加簡潔,通知響應處理方式也集中到了獨立的 delegate中,包括本地和遠程通知的處理。
func registerNotificationCategory() {
if #available(iOS 10.0, *) {
UNUserNotificationCenter.current().setNotificationCategories(createiOS10Category())
UNUserNotificationCenter.current().delegate = notificationHandler
} else {
let types: UIUserNotificationType = [.alert, .sound, .badge]
let settings = UIUserNotificationSettings(types: types, categories: createiOS89Category())
UIApplication.shared.registerUserNotificationSettings(settings)
}
}
// 當 application 處于前臺活躍狀態時會被調用,控制是否需要彈出提示
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
completionHandler([.alert, .sound, .badge])
}
// 當用戶點擊通知啟動 application,前臺活躍狀態點擊通知時都會被調用到
func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
completionHandler()
}
Content Extension 也可以在 application 未啟動前,處理已注冊過的通知分類
// 用戶每收到一條通知都會執行一次調用
func didReceive(_ notification: UNNotification) {
}
// 用戶點擊通知時會調用
func didReceive(_ response: UNNotificationResponse, completionHandler completion: @escaping (UNNotificationContentExtensionResponseOption) -> Swift.Void) {
}
3、編輯推送信息,簡單的示例 payload 如下:
{
"msgid": 100,
"aps":{
"alert":{
"title":"Image Notification",
"body":"Show me an image from web!"
},
"mutable-content":1
},
"image": "https://onevcat.com/assets/images/background-cover.jpg"
}
詳細定義參見 蘋果官方文檔。
4、Service Extension 和 Content Extension 都有獨立的 Bundle ID,打包時需要進行簽名,同時也需要配置 ATS
注意事項:
1、mutable-content 表示接收到通知時會對內容進行修改,必須配置為1,否則不會執行 Service Extension。
2、附件可以設置多個 attachment 實例,但系統默認只會顯示第一個,當然可以通告代碼修改它們的順序,以顯示最符合情景的圖片或者視頻。
3、extension 的 bundle 和 app main bundle 并不相同,屬于不同的沙盒目錄,也就是說當要使用內置資源時需添加進 extension 的 bundle 中。
4、如果使用的圖片和視頻文件不在 bundle 內部,它們將被移動到系統的負責通知的文件夾下,然后在當通知被移除后刪除。如果媒體文件在 bundle 內部,它們將被復制到通知文件夾下。每個應用能使用的媒體文件的文件大小總和是有限制,超過限制后創建 attachment 時將拋出異常,即不能同時創建太多的 attachment。
5、當訪問一個已經創建好的 attachment 時,需使用startAccessingSecurityScopedResource
來獲取訪問權限:
let content = notification.request.content
if let attachment = content.attachments.first {
if attachment.url.startAccessingSecurityScopedResource() {
eventImage.image = UIImage(contentsOfFile: attachment.url.path!)
attachment.url.stopAccessingSecurityScopedResource()
}
}
關于 Service Extension、Content Extension 和多媒體通知的使用,可以參考 Demo。