ios - 是什么阻止子图层与父图层一起移动？

Question

使用下面的代码，在需要的地方绘制 sublayer1 和 sublayer2。当动画发生时，sublayer1 按预期移动，而 sublayer2 最初向左上方移动，然后向右下方移动。（2不在1内保持在同一个地方）

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    // Create a blue sublayer 
    sublayer1 = [CALayer layer];
    sublayer1.backgroundColor = [[UIColor blueColor] CGColor];
    sublayer1.frame = CGRectMake(30, 30, 120, 190);
    sublayer1.position = CGPointMake(90, 130);
    [self.view.layer addSublayer:sublayer1];

    // Create a sublayer within blue layer
    CALayer *sublayer2 = [CALayer layer];
    sublayer2.bounds = CGRectMake(0, 0, 60, 60);
    sublayer2.frame = CGRectMake(30, 50, 60, 60);
    sublayer2.contents = (id)[[UIImage imageNamed:@"sun.png"] CGImage];
    [sublayer1 addSublayer:sublayer2];

    [self performSelector:@selector(moveBlueLayer) withObject:nil afterDelay:1.0];
}

- (void)moveBlueLayer
{
    // Create a new position for animation to move to
    CGPoint endPostition = CGPointMake(190, 285);

    [CATransaction setAnimationDuration:4];
    sublayer1.bounds = CGRectMake(130, 190, 120, 190);
    sublayer1.position = endPostition;
}

他们不是应该一起搬家吗？任何想法为什么他们不这样做？我现在正试图坚持“隐式”动画的解决方案。

Answer 1

从底部向上的第 3 行导致了不稳定的行为。

- (void)moveBlueLayer
{
   // Create a new position for animation to move to
   CGPoint endPostition = CGPointMake(190, 285);

   [CATransaction setAnimationDuration:4];
   // Next line causing the problem
   // sublayer1.bounds = CGRectMake(130, 190, 120, 190);
   sublayer1.position = endPostition;
}

Answer 2

不[sublayer1 addSublayer:flowerlayer];应该[sublayer1 addSublayer:sublayer2];吗？