IOS實現搖一搖原始碼__IOS

.h檔案

@interface ShakeViewController : UIViewController<UIAccelerometerDelegate>{    UIAccelerationValue    myAccelerometer[3];    //是否響應搖一搖的標誌    BOOL  _canShake;    }

.m檔案中

#define kFilteringFactor                0.1#define kEraseAccelerationThreshold        2.0@implementation ShakeViewController- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil{    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];    if (self) {        _canShake = YES;    }    return self;}- (void)dealloc{    [UIAccelerometer sharedAccelerometer].delegate = nil;    [super dealloc];}- (void)viewDidLoad{    [super viewDidLoad];    [UIAccelerometer sharedAccelerometer].delegate = self;    [UIAccelerometer sharedAccelerometer].updateInterval = 1.0f/40.0f;}#pragma mark - UIAccelerometerDelegate- (void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration{UIAccelerationValue  length, x, y, z;        if (!_canShake)    {        return;    }        //Use a basic high-pass filter to remove the influence of the gravity    myAccelerometer[0] = acceleration.x * kFilteringFactor + myAccelerometer[0] * (1.0 - kFilteringFactor);    myAccelerometer[1] = acceleration.y * kFilteringFactor + myAccelerometer[1] * (1.0 - kFilteringFactor);    myAccelerometer[2] = acceleration.z * kFilteringFactor + myAccelerometer[2] * (1.0 - kFilteringFactor);    // Compute values for the three axes of the acceleromater    x = acceleration.x - myAccelerometer[0];    y = acceleration.y - myAccelerometer[0];    z = acceleration.z - myAccelerometer[0];        //Compute the intensity of the current acceleration    length = sqrt(x * x + y * y + z * z);    // If above a given threshold, play the erase sounds and erase the drawing view    if(length >= kEraseAccelerationThreshold)    {        //是否響應搖一搖的標誌        _canShake = NO;        [self shakeEvent];    }}