怎么在iOS中添加一个购物车动画效果？相信很多没有经验的人对此束手无策，为此本文总结了问题出现的原因和解决方法，通过这篇文章希望你能解决这个问题。
一、计算动画开始结束点位置
方法：
- (CGPoint)convertPoint:(CGPoint)point toView:(nullable UIView *)view;
1） 动画开始位置fromCenter
复制代码 代码如下:
CGPoint fromCenter = [animationView convertPoint:CGPointMake(animationView.frame.size.width * 0.5f, animationView.frame.size.height * 0.5f) toView:keyWindow];
2）动画结束位置endCenter
复制代码 代码如下:
CGPoint endCenter = [endView convertPoint:CGPointMake(endView.frame.size.width * 0.5f, endView.frame.size.height * 0.5f) toView:keyWindow];
二、计算贝塞尔曲线（抛物线）的两个控制点
controlPoint1是控制点1
controlPoint2是控制点2
A是controlPoint1和controlPoint2的中点
controlPointC是fromCenter和B的中点
1）先设置控制点距最高点（fromCenter或endCenter）的水平距离controlPointEY，本篇默认controlPointEY = 100，即图1中点controlPointC到点A的距离。
2）计算控制点相对于点A的距离controlPointEX，即controlPoint1到A距离或controlPoint2到A距离，本篇设置为fromCenter.x到endCenter.x的1/4，即controlPointEX = (endCenter.x - fromCenter.x) * 0.25f;
3）计算两个控制点
CGPoint controlPoint1 = CGPointMake(controlPointCX - controlPointEX, controlPointCY - controlPointEY); CGPoint controlPoint2 = CGPointMake(controlPointCX + controlPointEX, controlPointCY - controlPointEY);
三、复制动画的layer
NSString *str = ((UIButton *)animationView).titleLabel.text; _animationLayer = [CATextLayer layer]; _animationLayer.bounds = animationView.bounds; _animationLayer.position = fromCenter; _animationLayer.alignmentMode = kCAAlignmentCenter;//文字对齐方式 _animationLayer.wrapped = YES; _animationLayer.contentsScale = [UIScreen mainScreen].scale; _animationLayer.string = str; _animationLayer.backgroundColor = [UIColor redColor].CGColor; [keyWindow.layer addSublayer:_animationLayer];
四、动画组合
1）运动轨迹（抛物线）
UIBezierPath *path = [UIBezierPath bezierPath]; [path moveToPoint:fromCenter]; [path addCurveToPoint:endCenter controlPoint1:controlPoint1 controlPoint2:controlPoint2]; CAKeyframeAnimation *pathAnimation = [CAKeyframeAnimation animationWithKeyPath:@"position"]; pathAnimation.path = path.CGPath;
2）旋转起来
CABasicAnimation *rotateAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation"]; rotateAnimation.removedOnCompletion = YES; rotateAnimation.fromValue = [NSNumber numberWithFloat:0]; rotateAnimation.toValue = [NSNumber numberWithFloat:10 * M_PI]; rotateAnimation.timingFunction=[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn]
3）缩放动画
CABasicAnimation *scaleAnimation = [CABasicAnimation animationWithKeyPath:@"transform.scale"]; scaleAnimation.removedOnCompletion = NO; scaleAnimation.fromValue = [NSNumber numberWithFloat:1.0]; scaleAnimation.toValue = [NSNumber numberWithFloat:0.2];
4）透明度动画
CABasicAnimation *alphaAnimation = [CABasicAnimation animationWithKeyPath:@"opacity"]; alphaAnimation.removedOnCompletion = NO; alphaAnimation.fromValue = [NSNumber numberWithFloat:1.0]; alphaAnimation.toValue = [NSNumber numberWithFloat:0.1];
5）动画组合
CAAnimationGroup *groups = [CAAnimationGroup animation]; groups.animations = @[pathAnimation,rotateAnimation, scaleAnimation, alphaAnimation]; groups.duration = kShoppingCartDuration; groups.removedOnCompletion=NO; groups.fillMode=kCAFillModeForwards; groups.delegate = self; [_animationLayer addAnimation:groups forKey:@"group"];
看完上述内容，你们掌握怎么在iOS中添加一个购物车动画效果的方法了吗？如果还想学到更多技能或想了解更多相关内容，欢迎关注创新互联网站建设公司行业资讯频道，感谢各位的阅读！
另外有需要云服务器可以了解下创新互联建站www.cdcxhl.com，海内外云服务器15元起步，三天无理由+7*72小时售后在线，公司持有idc许可证，提供“云服务器、裸金属服务器、高防服务器、香港服务器、美国服务器、虚拟主机、免备案服务器”等云主机租用服务以及企业上云的综合解决方案，具有“安全稳定、简单易用、服务可用性高、性价比高”等特点与优势，专为企业上云打造定制，能够满足用户丰富、多元化的应用场景需求。
