[10秒学会] - 动画组

// 同时缩放，平移，旋转
CAAnimationGroup *group = [CAAnimationGroup animation];

CABasicAnimation *scale = [CABasicAnimation animation];

scale.keyPath = @"transform.scale";
scale.toValue = @0.5;

CABasicAnimation *rotation = [CABasicAnimation animation];
rotation.keyPath = @"transform.rotation";
rotation.toValue = @(arc4random_uniform(M_PI));

CABasicAnimation *position = [CABasicAnimation animation];
position.keyPath = @"position";
position.toValue = [NSValue valueWithCGPoint:CGPointMake(arc4random_uniform(200), arc4random_uniform(200))];

group.animations = @[scale,rotation,position];

group.repeatCount = 3;
[group setAutoreverses:NO];
group.removedOnCompletion = NO; //不返回
group.fillMode = kCAFillModeForwards;
[_redView.layer addAnimation:group forKey:nil];