iOS 运动检测 : Motion Detection Sensitivity Levels

Question

我有一个简单的问题。我正在尝试检测用户何时摇动 iPhone。我有标准代码来检测运动，这没问题。但是，在我的实际手机上进行测试时，我意识到您必须非常用力地摇晃设备才能触发运动检测。我想知道是否有办法实现一定程度的敏感性检查。例如，一种检测用户是否轻轻摇晃设备或介于轻摇和剧烈摇晃之间的方法。这将针对 iOS 7，因此将不胜感激旧 iOS 版本未弃用的任何提示或建议。我已经完成了谷歌搜索，但还没有找到解决这个问题的任何好的方法(如果有的话。)

谢谢!

-(void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event
{
    if(motion == UIEventSubtypeMotionShake)
    {
       //Detected motion, do something about it 
       //at this point.
    }
}

-(BOOL)canBecomeFirstResponder
{
    return YES;
}

-(void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];
    [self becomeFirstResponder];
}

-(void)viewWillDisappear:(BOOL)animated
{
    [self resignFirstResponder];
    [super viewWillDisappear:animated];
}

Answer 1

这是我找到的解决方案。这很好用，但你必须使用 deviceMotionUpdateInterval 时间值以及 accelerationThreshold 这可能很难获得实际“轻摇”与“拿起手机并将其靠近你的脸等”的良好平衡...”可能有更好的方法，但这里是一个开始。在我的 View didLoad 中，我做了这样的事情:

#import <CoreMotion/CoreMotion.h> //do not forget to link the CoreMotion framework to your project
#define accelerationThreshold  0.30 // or whatever is appropriate - play around with different values

-(void)viewDidLoad
{
      CMMotionManager *motionManager; 

      motionManager = [[CMMotionManager alloc] init];
      motionManager.deviceMotionUpdateInterval = 1;

      [motionManager startDeviceMotionUpdatesToQueue:[NSOperationQueue currentQueue]  withHandler:^(CMDeviceMotion *motion, NSError *error)
             {
                [self motionMethod:motion];
             }];
}

-(void)motionMethod:(CMDeviceMotion *)deviceMotion
{
    CMAcceleration userAcceleration = deviceMotion.userAcceleration;
    if (fabs(userAcceleration.x) > accelerationThreshold
        || fabs(userAcceleration.y) > accelerationThreshold
        || fabs(userAcceleration.z) > accelerationThreshold)
        {
           //Motion detected, handle it with method calls or additional
           //logic here.
           [self foo];
        }
}