如何在iPhone上检测屏幕锁定/解锁事件？

Question

如何在iPhone上检测屏幕锁定/解锁事件？当用户解锁它时，我想从我的iPhone应用程序中显示一个通知警报。(就像Android的屏幕解锁的广播接收器一样。)

Answer 1

看看这个，我想检测锁定/解锁事件，我通过Darwin通知解决了这个问题。您可以在设备被"com.apple.springboard.lockcomplete"锁定时检测到该事件。

//call back
static void displayStatusChanged(CFNotificationCenterRef center, void *observer, CFStringRef name, const void *object, CFDictionaryRef userInfo)
{
    // the "com.apple.springboard.lockcomplete" notification will always come after the "com.apple.springboard.lockstate" notification

    NSString *lockState = (NSString*)name;
    NSLog(@"Darwin notification NAME = %@",name);

    if([lockState isEqualToString:@"com.apple.springboard.lockcomplete"])
    {
        NSLog(@"DEVICE LOCKED");
    }
    else
    {
        NSLog(@"LOCK STATUS CHANGED");
    }   
}


-(void)registerforDeviceLockNotif
{
    //Screen lock notifications
    CFNotificationCenterAddObserver(CFNotificationCenterGetDarwinNotifyCenter(), //center
                                    NULL, // observer
                                    displayStatusChanged, // callback
                                    CFSTR("com.apple.springboard.lockcomplete"), // event name
                                    NULL, // object
                                    CFNotificationSuspensionBehaviorDeliverImmediately);

    CFNotificationCenterAddObserver(CFNotificationCenterGetDarwinNotifyCenter(), //center
                                    NULL, // observer
                                    displayStatusChanged, // callback
                                    CFSTR("com.apple.springboard.lockstate"), // event name
                                    NULL, // object
                                    CFNotificationSuspensionBehaviorDeliverImmediately);  
}   

Answer 2

要在swift 5中检测应用程序中的锁定/解锁，只有这一点对我有效：

override func viewDidLoad() {
    super.viewDidLoad()

     NotificationCenter.default.addObserver(self, selector: #selector(applicationDidBecomeActive), name: UIApplication.willEnterForegroundNotification, object: nil)
     NotificationCenter.default.addObserver(self, selector: #selector(applicationDidEnterBackground), name: UIApplication.didEnterBackgroundNotification, object: nil)
}

@objc func applicationDidBecomeActive(notification: NSNotification) {
    print("ACTIVE")
}
@objc func applicationDidEnterBackground(notification: NSNotification) {
    print("BACKGROUND")
}

Answer 3

1. 你不能使用com.apple.springboard.lockcomplete或com.apple.springboard.lockstate将你的应用提交到应用商店时，你的应用将被拒绝，因为它是私有API。
2. com.apple.springboard.lockcomplete通知并不总是在com.apple.springboard.lockstate通知之后出现，它可能早晚发生。您需要设置一个计时器来等待该事件。

下面是你在Swift 5中检测屏幕锁定和解锁状态的方法：

struct NotificationName {
    // Listen to CFNotification, and convert to Notification
    public static let lockComplete = Notification.Name("NotificationName.lockComplete")
    public static let lockState = Notification.Name("NotificationName.lockState")

    // Handle lockComplete and lockState Notification to post locked or unlocked notification.
    public static let locked = Notification.Name("NotificationName.locked")
    public static let unlocked = Notification.Name("NotificationName.unlocked")
}

func addNotificationObservers() {
    let lockCompleteString = "com.apple.springboard.lockcomplete"
    let lockString = "com.apple.springboard.lockstate"

    // Listen to CFNotification, post Notification accordingly.
    CFNotificationCenterAddObserver(CFNotificationCenterGetDarwinNotifyCenter(),
                                    nil,
                                    { (_, _, _, _, _) in
                                        NotificationCenter.default.post(name: NotificationName.lockComplete, object: nil)
                                    },
                                    lockCompleteString as CFString,
                                    nil,
                                    CFNotificationSuspensionBehavior.deliverImmediately)

    CFNotificationCenterAddObserver(CFNotificationCenterGetDarwinNotifyCenter(),
                                    nil,
                                    { (_, _, _, _, _) in
                                        NotificationCenter.default.post(name: NotificationName.lockState, object: nil)
                                    },
                                    lockString as CFString,
                                    nil,
                                    CFNotificationSuspensionBehavior.deliverImmediately)

    // Listen to Notification and handle.
    NotificationCenter.default.addObserver(self,
                                            selector: #selector(onLockComplete),
                                            name: NotificationName.lockComplete,
                                            object: nil)

    NotificationCenter.default.addObserver(self,
                                            selector: #selector(onLockState),
                                            name: NotificationName.lockState,
                                            object: nil)
}

// nil means don't know; ture or false means we did or did not received such notification.
var receiveLockStateNotification: Bool? = nil
// when we received lockState notification, use timer to wait 0.3s for the lockComplete notification.
var waitForLockCompleteNotificationTimer: Timer? = nil
var receiveLockCompleteNotification: Bool? = nil

// When we received lockComplete notification, invalidate timer and refresh lock status.
@objc
func onLockComplete() {
    if let timer = waitForLockCompleteNotificationTimer {
        timer.invalidate()
        waitForLockCompleteNotificationTimer = nil
    }

    receiveLockCompleteNotification = true
    changeIsLockedIfNeeded()
}

// When we received lockState notification, refresh lock status.
@objc
func onLockState() {
    receiveLockStateNotification = true
    changeIsLockedIfNeeded()
}

func changeIsLockedIfNeeded() {
    guard let state = receiveLockStateNotification, state else {
        // If we don't receive lockState notification, return.
        return
    }

    guard let complete = receiveLockCompleteNotification else {
        // If we don't receive lockComplete notification, wait 0.3s.
        // If nothing happens in 0.3s, then make sure we don't receive lockComplete, and refresh lock status.
        waitForLockCompleteNotificationTimer = Timer.scheduledTimer(withTimeInterval: 0.3, repeats: false, block: { _ in
            self.receiveLockCompleteNotification = false
            self.changeIsLockedIfNeeded()
        })
        return
    }

    // When we determined lockState and lockComplete notification is received or not.
    // We can update the device lock status by 'complete' value.
    NotificationCenter.default.post(
        name: complete ? NotificationName.locked : NotificationName.unlocked,
        object: nil
    )

    // Reset status.
    receiveLockStateNotification = nil
    receiveLockCompleteNotification = nil
}