Shake Animation in xcode

    CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"position"];

    [animation setDelegate:self]; 

    [UIView setAnimationDidStopSelector:@selector(animationDidStop:finished:)];

    [animation setDuration:0.05];

    [animation setRepeatCount:4];

    [animation setAutoreverses:YES];

    [animation setFromValue:[NSValue valueWithCGPoint:

                             CGPointMake([v center].x - 14.0f, [v center].y)]];

    [animation setToValue:[NSValue valueWithCGPoint:

                           CGPointMake([v center].x + 14.0f, [v center].y)]];

    [[v layer] addAnimation:animation forKey:@"position"];