前言

一个简单的利用透明度和缩放实现的数字倍数动画

实现思路

上代码看比较清晰

// 数字跳动动画- (void)labelDanceAnimation:(NSTimeInterval)duration {    //透明度    CABasicAnimation *opacityAnimation = [CABasicAnimation animationWithKeyPath:@"opacity"];    opacityAnimation.duration = 0.4 * duration;    opacityAnimation.fromValue = @0.f;    opacityAnimation.toValue = @1.f;    //缩放    CAKeyframeAnimation *scaleAnimation = [CAKeyframeAnimation animationWithKeyPath:@"transform.scale"];    scaleAnimation.duration = duration;    scaleAnimation.values = @[@3.f, @1.f, @1.2f, @1.f];    scaleAnimation.keyTimes = @[@0.f, @0.16f, @0.28f, @0.4f];    scaleAnimation.removedOnCompletion = YES;    scaleAnimation.fillMode = kCAFillModeForwards;    CAAnimationGroup *animationGroup = [CAAnimationGroup animation];    animationGroup.animations = @[opacityAnimation, scaleAnimation];    animationGroup.duration = duration;    animationGroup.removedOnCompletion = YES;    animationGroup.fillMode = kCAFillModeForwards;    [self.comboLabel.layer addAnimation:animationGroup forKey:@"kComboAnimationKey"];}

利用一个透明度从 0 ~ 1之间的alpha,然后缩放之后加到动画组实现一下就好了

切记动画完成最好移除否则可能引起动画内存问题

这里设置斜体字体

self.comboLabel.font = [UIFont fontWithName:@"AvenirNext-BoldItalic" size:50];

看着比较明显

最后按钮点击的时候调用

- (IBAction)clickAction:(UIButton *)sender {    self.danceCount++;    [self labelDanceAnimation:0.4];    self.comboLabel.text = [NSString stringWithFormat:@"+  %tu",self.danceCount];}

如果实现 dozen动画的话很简单, danceCount % 10 == 0 求模就行了.