- 首先我要说的是点击加入购物车按钮弹出View的动画解析，而不是什么点击商品图片飞来飞去的动画，效果是这样的：
taobao2.gif
- 乍一看很简单，不就把它放大缩小一下，你要这么做效果那真是惨不能睹，仔细观察手机淘宝这个动画效果，一气呵成，有3D效果，像一张纸一样往下落的感觉。由于产品的需求，一开始毫无头绪，网上的第三方做出效果我很不满意：
disanfang.gif
动画过程给人感觉很突兀，衔接不够流畅，一个动画需要两个阶段完成，这就导致不够顺滑。
该动画效果可以由缩小，旋转，平移，下落动画并发执行得到的结果，可以使用核心动画组来实现并发的动画；
View弹出的动画：背景下落，popview弹出，使用核心动画组实现
x， y轴方向分别缩放，z轴方向下落，根据锚点绕x轴旋转，再加入y轴方向的平移，使其有飘来飘去的感觉。
效果如下：
popView.gif
代码如下：
popView出现的时候：
//该方法是并发，所以不影响核心动画的执行，为什么需要这个方法，因为我们还需要对popview和coverView进行操作，对不需要操作的self.View就可以使用核心动画
[UIView animateWithDuration:0.5 animations:^{
popView.yqh_y = (MAINHEIGHT - 280);
coverView.alpha = 0.3;
}];
//注意设置锚点和位置点，因为旋转和缩放都是按照锚点来的
self.view.layer.anchorPoint = CGPointMake(0.5, 0.8);
self.view.layer.position = CGPointMake(self.view.yqh_width * .5, self.view.yqh_height * .8);
CATransform3D tran = CATransform3DIdentity;
//设置近大远小的效果，值越大效果越明显，所以不要太大
tran.m34 = -1.0/1000;
self.view.layer.transform = tran;
//核心动画也是并发
CABasicAnimation *scaleAnimateX = [CABasicAnimation animationWithKeyPath:@"transform.scale.x"];
scaleAnimateX.toValue = @(0.9);
//延迟0.2秒执行
scaleAnimateX.beginTime = 0.2;
CABasicAnimation *scaleAnimateY = [CABasicAnimation animationWithKeyPath:@"transform.scale.y"];
scaleAnimateY.toValue = @(0.9);
scaleAnimateY.beginTime = 0.2;
CABasicAnimation *positonY = [CABasicAnimation animationWithKeyPath:@"transform.translation.y"];
positonY.toValue = @(-60);
CABasicAnimation *positonZ = [CABasicAnimation animationWithKeyPath:@"transform.translation.z"];
positonZ.toValue = @(-100);
CAKeyframeAnimation *rotation = [CAKeyframeAnimation animation];
rotation.keyPath = @"transform.rotation.x";
rotation.values = @[@(0), @(15 / 180.0 * M_PI), @(0)];
rotation.repeatCount = 1;
CAAnimationGroup *group = [CAAnimationGroup animation];
group.animations = @[scaleAnimateX, scaleAnimateY, rotation, positonY, positonZ];
group.duration = 0.5;
//动画结束不恢复原状
group.removedOnCompletion = NO;
group.fillMode = kCAFillModeForwards;
[self.view.layer addAnimation:group forKey:nil];
popView消失的时候：
[UIView animateWithDuration:0.5 animations:^{
//popview消失
self.popView.yqh_y = MAINHEIGHT;
self.coverView.alpha = 0;
}completion:^(BOOL finished) {
[self.popView removeFromSuperview];
[self.coverView removeFromSuperview];
//移除动画
[self.view.layer removeAllAnimations];
//恢复默认的锚点和位置点
self.view.layer.anchorPoint = CGPointMake(0.5, 0.5);
self.view.layer.position = CGPointMake(self.view.yqh_width * .5, self.view.yqh_height * .5);
}];
//恢复的动画跟上面的相反
CATransform3D tran = CATransform3DIdentity;
tran.m34 = -1.0/1000;
self.view.layer.transform = tran;
CABasicAnimation *scaleAnimateX = [CABasicAnimation animationWithKeyPath:@"transform.scale.x"];
scaleAnimateX.toValue = @(1.0);
CABasicAnimation *scaleAnimateY = [CABasicAnimation animationWithKeyPath:@"transform.scale.y"];
scaleAnimateY.toValue = @(1.0);
CABasicAnimation *positonY = [CABasicAnimation animationWithKeyPath:@"transform.translation.y"];
positonY.toValue = @(0);
CABasicAnimation *positonZ = [CABasicAnimation animationWithKeyPath:@"transform.translation.z"];
positonZ.toValue = @(0);
CAKeyframeAnimation *rotation = [CAKeyframeAnimation animation];
rotation.keyPath = @"transform.rotation.x";
rotation.values = @[@(0), @(15 / 180.0 * M_PI), @(0)];
rotation.repeatCount = 1;
CAAnimationGroup *group = [CAAnimationGroup animation];
group.animations = @[scaleAnimateX, scaleAnimateY, rotation, positonY, positonZ];
group.duration = 0.5;
group.removedOnCompletion = NO;
group.fillMode = kCAFillModeForwards;
[self.view.layer addAnimation:group forKey:nil];
唉，也懒得封装了，大家可以给uiviewcontroller写个分类，到时候就可以用上了。。。
