a UIView category for shaking

UIView+ZDShake

- (void)zd_shake:(CGFloat)range {
    CAKeyframeAnimation *animation = [CAKeyframeAnimation animationWithKeyPath:@"transform.translation.y"];
    animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear];
    animation.duration = 0.5;
    animation.values = @[@(-range), @(range), @(-range/2), @(range/2), @(-range/5), @(range/5), @(0)];
    animation.repeatCount = CGFLOAT_MAX;
    [self.layer addAnimation:animation forKey:@"shake"];
}