简介
在 iOS 10 中新加入 UserNotifications 框架,对以往杂乱无章的通知系统 API 进行了统一,更方便开发者们快速引用。关于新框架的一些基本概念在喵大的《iOS 10 UserNotifications 框架解析》中已有详细的描述,本文只对实践中的具体运用做介绍。
基本流程
iOS 10中通知相关操作遵循下面的流程:
权限申请
iOS 各个版本 Notifications 权限申请代码如下:
// iOS 10 support
if #available(iOS 10.0, *) {
let options: UNAuthorizationOptions = [.alert, .sound, .badge]
UNUserNotificationCenter.current().requestAuthorization(options: options) { granted, error in
if granted {
// 用户允许进行通知
}
}
}
// 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 != [] {
// 用户允许进行通知
}
}
// 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 != [] {
// 用户允许进行通知
}
}
// iOS 7 support
else {
let types: UIRemoteNotificationType = [.badge, .sound, .alert]
UIApplication.shared.registerForRemoteNotifications(matching: types)
}
注册Token
当用户同意授权以后,还需要向系统注册一个 Device Token,并将这个 token 发送到 APNs(Apple Push Notification Service),然后 APNs 通过 token 识别设备和应用,并通知推送给用户。
// 向 APNs 请求 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)")
// 上传至后台服务器
}
// 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)")
}
发送推送通知
关于 APNs 的推送原理 就不做详细说明,这里以 Node.js 为例子搭建推送测试工具,步骤如下:
1、创建 APNs 服务的访问 Auth Key ID
2、获取 Key ID,点击 Download 同时下载 .p8 证书文件
3、获取开发者账号的 Team ID
4、编写测试脚本 push.js,内容如下:
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>");
}
至此就可以测试远程推送通知了。当然还可以其他类似的工具 NWPusher
node push.js 8c6f8b7056613a5223c690fb171697c524173b9c39e7dff688c66f0b23fbefdb
展示处理
iOS 10以前通知完全是系统行为,开发者无法自主控制,引入 UserNotifications 框架以后通知数据处理流程如下:
其中 Service Extension 和 Content Extension 前者可以让我们有机会在收到远程推送的通知后,展示之前对通知内容进行修改;后者可以用来自定义通知视图UI的样式。尤其是Service Extension收到通知以后必执行,iOS平台终于可以做更精准的推送到达率统计了。
1、创建 Service Extension,Xcode 会自动生成模板代码。在这里可以进行埋点统计,并在通知中展示多媒体文件(图片/音频/视频)。
class NotificationService: UNNotificationServiceExtension {
var contentHandler: ((UNNotificationContent) -> Void)?
var bestAttemptContent: UNMutableNotificationContent?
/**
该方法可以在限定时间内(30秒)修改请求中的 content 内容,然后返回给系统显示
*/
override func didReceive(_ request: UNNotificationRequest, withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void) {
self.contentHandler = contentHandler
bestAttemptContent = (request.content.mutableCopy() as? UNMutableNotificationContent)
if let bestAttemptContent = bestAttemptContent {
// 进行 Push 到达的埋点统计
var msgid = 1
if let tmp = bestAttemptContent.userInfo["msgid"] as? NSNumber {
msgid = tmp.intValue
}
tracePush(msgId: msgId)
/**
添加多媒体附件
内置资源支持10MB以内图片,50M以内音视频
外链支持30秒内能下载完成的多媒体文件
*/
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)
}
}
}
/**
一定时间内(30秒)没将内容返回给系统,则会自动调用该方法,未完成的修改将被忽略
*/
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、创建 Content Extension,Xcode 会自动生成模板代码(若不需要自定义UI,可跳过本部分)。iOS 10中通知分类注册方式更加简洁,通知响应处理方式也集中到了独立的 delegate中,包括本地和远程通知的处理。
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)
}
}
// 当 application 处于前台活跃状态时会被调用,控制是否需要弹出提示
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
completionHandler([.alert, .sound, .badge])
}
// 当用户点击通知启动 application,前台活跃状态点击通知时都会被调用到
func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
completionHandler()
}
Content Extension 也可以在 application 未启动前,处理已注册过的通知分类
// 用户每收到一条通知都会执行一次调用
func didReceive(_ notification: UNNotification) {
}
// 用户点击通知时会调用
func didReceive(_ response: UNNotificationResponse, completionHandler completion: @escaping (UNNotificationContentExtensionResponseOption) -> Swift.Void) {
}
3、编辑推送信息,简单的示例 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"
}
详细定义参见 苹果官方文档。
4、Service Extension 和 Content Extension 都有独立的 Bundle ID,打包时需要进行签名,同时也需要配置 ATS
注意事项:
1、mutable-content 表示接收到通知时会对内容进行修改,必须配置为1,否则不会执行 Service Extension。
2、附件可以设置多个 attachment 实例,但系统默认只会显示第一个,当然可以通告代码修改它们的顺序,以显示最符合情景的图片或者视频。
3、extension 的 bundle 和 app main bundle 并不相同,属于不同的沙盒目录,也就是说当要使用内置资源时需添加进 extension 的 bundle 中。
4、如果使用的图片和视频文件不在 bundle 内部,它们将被移动到系统的负责通知的文件夹下,然后在当通知被移除后删除。如果媒体文件在 bundle 内部,它们将被复制到通知文件夹下。每个应用能使用的媒体文件的文件大小总和是有限制,超过限制后创建 attachment 时将抛出异常,即不能同时创建太多的 attachment。
5、当访问一个已经创建好的 attachment 时,需使用startAccessingSecurityScopedResource
来获取访问权限:
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()
}
}
关于 Service Extension、Content Extension 和多媒体通知的使用,可以参考 Demo。