Question

我正在尝试制作一个呼吸圈动画。只有breathInAnimation（成长圈）似乎有生气。调用breathOutAnimation（缩小圆圈），但似乎没有做任何事情。我猜它会立即恢复到起始状态，但我不明白为什么。

- （void）viewDidLoad

 animationView = [[UIView alloc] initWithFrame:CGRectMake(self.view.frame.size.width / 2.0, self.view.frame.size.height / 2.0, 200, 200)];
 animationView.backgroundColor = [UIColor blueColor];
 animationView.layer.cornerRadius = 100;
 animationView.center = self.view.center;
[self.view addSubview: animationView];


[self drawCircleEdge];
[self breathInAnimation];
[NSTimer timerWithTimeInterval:7.0 target:self selector:@selector(breathOutAnimation) userInfo:nil repeats:YES];

- （void）breathInAnimation

    CABasicAnimation *scaleAnimation = [CABasicAnimation animationWithKeyPath:@"transform.scale"];
    [scaleAnimation setValue:@"breathIn" forKey:@"id"];
    scaleAnimation.duration = 4;
    scaleAnimation.fromValue = [NSNumber numberWithFloat:0.1];
    scaleAnimation.toValue = [NSNumber numberWithFloat:1];
    [animationView.layer addAnimation:scaleAnimation forKey:@"scale"];

- （无效）breathOutAnimation

    CABasicAnimation *breathOut = [CABasicAnimation animationWithKeyPath:@"transform.scale"];
    breathOut.duration = 8;
    breathOut.fromValue = [NSNumber numberWithFloat:1];
    breathOut.toValue = [NSNumber numberWithFloat:0.1];
    [animationView.layer removeAllAnimations];
   [animationView.layer addAnimation: breathOut forKey:@"scale"];

我也尝试过使用scaleAnimation的委托。

- (void)animationDidStop:(CABasicAnimation *)theAnimation2 finished:(BOOL)flag

这有效，但在动画完成后，圆圈会回到结束第一个动画后的状态。收缩 - ＆gt;动画结束 - ＆gt;再次全力以赴。

我不确定我在这里缺少什么。

Answer 1

CAAnimations不会将转换应用于您的图层，它会在表示层上设置动画，然后在动画完成时切换回您的图层。

您应该在播放动画时应用变换。

-(void)breathOutAnimation
{
    CABasicAnimation *breathOut = [CABasicAnimation animationWithKeyPath:@"transform.scale"];
    breathOut.duration = 8;
    breathOut.fromValue = [NSNumber numberWithFloat:1];
    breathOut.toValue = [NSNumber numberWithFloat:0.1];
    [animationView.layer removeAllAnimations];
    [animationView.layer addAnimation: breathOut forKey:@"scale"];
    animationView.layer.transform = CATransform3DMakeScale(0.1, 0.1, 0.1);
}

结束或触发第二个动画后动画重置为开始状态

1 个答案: