苹果在 WWDC22 中，提出了实时活动（Live Activity）的概念，以便于用户在锁屏查看一些应用实时活动的更新。并且ActivityKit实现了灵动岛视图的自定义。
iOS16.1 锁屏界面上新增了实时活动界面，目前仅有iPhone 14 Pro和iPhone 14 Pro Max 两款机型上拥有灵动岛。实时活动包括了锁屏界面和灵动岛界面两个部分的内容，示例如下图所示：

22871a00574944c58c8e014048ce7eb1.png

与锁屏Live Activity共享数据，在支持灵动岛的机型下，用户在非锁屏页面时，信息的更新会以灵动岛的形式展示更新
Live Activity创建后，灵动岛就可以进行点击响应了，如果不适配的话，点击灵动岛会自动进入主程序，并且长按会变成一个没有任何信息的黑块
iPhone14 Pro、iPhone14 Pro Max用户占比逐渐升高
开发基础知识（节选自参考文献2）
设备只支持iPhone，并且是有“药丸屏”的iPhone14Pro和14Pro Max上；
Max系统版本、编译器及iOS系统版本：>=MacOS12.4、>=Xcode14.0+beta4、>=iOS16.1+beta；
使用 ActivityKit 用于配置、开始、更新、结束实现 Live Activity 能力。使用 WidgetKit 、SwiftUI在widget小组件中创建 Live Activity的用户界面，这样小组件和 Live Activity的代码是可以共享；
Live Activity目前只能通过 ActivityKit 从主工程获取数据，或者从 远程通知 获取最新数据；无法访问网络或者接受位置更新信息
ActivityKit 和 远程通知推送 更新的数据不能超过4KB；
Live Activity可以给不同的控制绑定不同的 deeplink，使其跳转到不同的页面；
Live Activity在用户主动结束前最多存活8小时；
已经结束的 Live Activity 在锁屏也最多保留4小时，所以一个Live Activity 最长可以停留12小时；
最多同时存在两组 Live Activity ，排列顺序待发现
Live Activity只有Swift版本，项目是 OC的话需要桥接。
1，需要在主程序的Info.plist中添加键值：Supports Live Activities为YES
2，创建WidgetExtension
如果项目中已经有WidgetExtension，可以直接快进到第二步。

630d4db34ff84c6a91c344be0348ae22.png

3，认识相关设置

d24ef416fe794fe9b147aae0e0b8c2d1.png

f9bb60547e5948879e64050445c494c7.png

4，定义数据类型：
struct ActivityWidgetAttributes: ActivityAttributes {
public struct ContentState: Codable, Hashable {
var nickname: String // 用户对象的昵称 动态变量
......
}
// Fixed non-changing properties about your activity go here!
var name: String //静态变量
}
5，实时活动的开启、更新和结束都需要在主程序进行管理。
//开启 使用方法
public static func request(attributes: Attributes, contentState: Activity<Attributes>.ContentState, pushType: PushType? = nil) throws -> Activity<Attributes>

private var myActivity: Activity<ActivityWidgetAttributes>? = nil

let initialContentState = ActivityWidgetAttributes.ContentState(nickName: "哈哈哈")
let activityAttributes = ActivityWidgetAttributes(name: "嘻嘻嘻")
do {
// 本地更新的创建方式
myActivity = try Activity.request(attributes: activityAttributes, contentState: initialContentState)
// 通知更新的创建方式,需要传递pushType: .token
myActivity = try Activity.request(attributes: activityAttributes, contentState: initialContentState, pushType: .token)
print("Activity id : (String(describing: cymActivity?.id ?? "nil")).")
} catch (let error) {
print("ActivityError: (error.localizedDescription)" )
}
6，// 更新使用方法
public func update(using contentState: Activity<Attributes>.ContentState, alertConfiguration: AlertConfiguration? = nil) async

// 更新内容
let updateStatus = ActivityWidgetAttributes.ContentState(nickName: "啊啊啊")
// 关于通知的配置
let alertConfiguration = AlertConfiguration(title: "111", body: "2222", sound: .default)
Task {
await myActivity?.update(using: updateStatus, alertConfiguration: alertConfiguration)
}
7，// 使用方法
public func end(using contentState: Activity<Attributes>.ContentState? = nil, dismissalPolicy: ActivityUIDismissalPolicy = .default) async
// 结束策略有3种
/// The system's default dismissal policy for the Live Activity.
///
/// With the default dismissal policy, the system keeps a Live Activity that ended on the Lock Screen for
/// up to four hours after it ends or the user removes it. The ActivityKit/ActivityState
/// doesn't change to ActivityKit/ActivityState/dismissed until the user or the system
/// removes the Live Activity user interface.
public static let default: ActivityUIDismissalPolicy

/// The system immediately removes the Live Activity that ended.
///
/// With the `immediate` dismissal policy, the system immediately removes the ended Live Activity
/// and the ``ActivityKit/ActivityState`` changes to
/// ``ActivityKit/ActivityState/dismissed``.
public static let immediate: ActivityUIDismissalPolicy

/// The system removes the Live Activity that ended at the specified time within a four-hour window.
/// 
/// Provide a date to tell the system when it should remove a Live Activity that ended. While you can
/// provide any date, the system removes a Live Activity that ended after the specified date or after four
/// hours from the moment the Live Activity ended — whichever comes first. When the system
/// removes the Live Activity,  the ``ActivityKit/ActivityState`` changes to ``ActivityKit/ActivityState/dismissed``.
///
/// - Parameters:
///     - date: A date within a four-hour window from the moment the Live Activity ends.
public static func after(_ date: Date) -> ActivityUIDismissalPolicy

Task {
await myActivity?.end(using:nil, dismissalPolicy: .immediate)
}
8状态获取：创建成功后可以使用activityStateUpdates监听到实时活动的状态
Task.detached {
for awaitactivity in Activity<ActivityWidgetAttributes>.activities {
for await state in activity.activityStateUpdates {
if (state == .active) {
/// The Live Activity is active, visible to the user, and can receive content updates.
} else if (state == .ended) {
/// The Live Activity is visible, but the user, app, or system ended it, and it won't update its content anymore.
} else { // .dismissed
/// The Live Activity ended and is no longer visible because the user or the system removed it.
}
}
}
}
9.PushToken获取
如果需要使用通知进行更新，需要将PushToken发送给服务端。
// 创建时需要 pushType: .token
Activity.request(attributes: activityAttributes, contentState: initialContentState, pushType: .token)
// 创建成功后
Task.detached {
for await activity in Activity<ActivityWidgetAttributes>.activities {
for await pushToken in activitie.pushTokenUpdates {
let mytoken = pushToken.map {String(format: "%02x", $0)}.joined().uppercased()
// pushToken 是Data 需要经过上面的方法 转换成String传递给服务端使用
print("push token", mytoken)
}
}
}
}
10，设置中打开权限

bff206c0d0384b7a9cd127987d3f63ff.png

11，实时活动的权限无法监听获得，只能主动进行判断，需要在进行创建前进行判断来提示用户
// 实时活动是否可用，包括权限是否开启和手机是否支持实时活动
ActivityAuthorizationInfo().areActivitiesEnabled
// 获取已有的实时活动个数
Activity<ActivityWidgetAttributes>.activities.count