4

当用户将 iphone 举到脸上时，我想得到通知。就像siri一样。是否可以？

添加更具体的要求：当用户将手机靠近耳朵时，我想使屏幕变暗。我知道接近传感器可以实现这一点。但令人讨厌的是，当用户在传感器上移动手指时，屏幕会不时变暗。所以我想知道如何避免这种情况，只在用户举起 iphone 说话时才使屏幕变暗？

4

2 回答 2

7

请参阅UIDevice 类参考中的使用接近传感器。那么你：

  • 启用它：

    UIDevice *device = [UIDevice currentDevice];
device.proximityMonitoringEnabled = YES;

  • 检查是否启用成功；如果成功，请观察UIDeviceProximityStateDidChangeNotification通知；如果没有，您的设备可能无法：

    if (device.proximityMonitoringEnabled)
{
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(handleProximityChange:)
                                                 name:UIDeviceProximityStateDidChangeNotification
                                               object:nil];
}
else
{
     // device not capable
}

  • 并编写您的选择器：

    - (void)handleProximityChange:(NSNotification *)notification
{
    NSLog(@"%s proximityState=%d", __FUNCTION__, [[UIDevice currentDevice] proximityState]);
}

为了检测用户是否将手机举到了脸上，我可能会将接近传感器与手机结合起来，CMMotionManager然后查看gravity属性，看看他们是否几乎垂直地拿着手机。因此，定义一些类属性：

@property (nonatomic, strong) CMMotionManager *motionManager;
@property (nonatomic, strong) NSOperationQueue *deviceQueue;

然后您可以启动CMMotionManager，查看设备是否保持在垂直位置：

self.deviceQueue = [[NSOperationQueue alloc] init];
self.motionManager = [[CMMotionManager alloc] init];
self.motionManager.deviceMotionUpdateInterval = 5.0 / 60.0;

UIDevice *device = [UIDevice currentDevice];

[self.motionManager startDeviceMotionUpdatesUsingReferenceFrame:CMAttitudeReferenceFrameXArbitraryZVertical
                                                        toQueue:self.deviceQueue
                                                    withHandler:^(CMDeviceMotion *motion, NSError *error)
{
    BOOL vertical = (motion.gravity.z > -0.4 && motion.gravity.z < 0.4 & motion.gravity.y < -0.7);
    if ((vertical && !device.proximityMonitoringEnabled) || (!vertical && device.proximityMonitoringEnabled))
    {
        device.proximityMonitoringEnabled = vertical;
    }
}];

这些gravity阈值是否有意义有点主观。您还可以查看其他加速度计数据（例如，他们是否举起物体），而不仅仅是查看手机是否大致垂直握持。似乎有很多方法可以给猫剥皮。

于 2013-03-19T02:24:40.647 回答
2

我知道这很旧，但我稍微简化了逻辑并在 Swift 中创建了一个包装类。

你可以在这里找到它

class DeviceRaisedToEarListener: NSObject {
private let deviceQueue = NSOperationQueue()
private let motionManager = CMMotionManager()
private var vertical: Bool = false

private(set) var isRaisedToEar: Bool = false {
    didSet {
        if oldValue != self.isRaisedToEar {
            self.stateChanged?(isRaisedToEar: self.isRaisedToEar)
        }
    }
}

var stateChanged:((isRaisedToEar: Bool)->())? = nil

override init() {
    super.init()
    self.setupMotionManager()
}

private func setupMotionManager() {
    self.motionManager.deviceMotionUpdateInterval = 5.0 / 60.0
    let device = UIDevice.currentDevice()

    // Only listen for proximity changes if the device is held vertically
    self.motionManager.startDeviceMotionUpdatesUsingReferenceFrame(CMAttitudeReferenceFrame.XArbitraryZVertical, toQueue: self.deviceQueue) { (motion, error) in
        self.vertical = (motion.gravity.z > -0.4 && motion.gravity.z < 0.4 && motion.gravity.y < -0.7)
    }
}

func startListening() {
    UIDevice.currentDevice().proximityMonitoringEnabled = true
    NSNotificationCenter.defaultCenter().addObserver(self, selector: "handleProximityChange:", name: UIDeviceProximityStateDidChangeNotification, object: nil)
}

func stopListening() {
    UIDevice.currentDevice().proximityMonitoringEnabled = false
    NSNotificationCenter.defaultCenter().removeObserver(self)
}

func handleProximityChange(notification: NSNotification) {
    self.isRaisedToEar = UIDevice.currentDevice().proximityState && self.vertical
}

deinit {
    self.stopListening()
}
}


// How to use:
private func setupRaiseListener() {
    self.deviceListener.stateChanged = { [weak self] isRaisedToEar in
      println("is raised? \(isRaisedToEar)")
    }
    self.deviceListener.startListening()
}
于 2015-11-03T18:48:53.033 回答