ios - 循环动画

Question

我想实现一个动画，它就像从一个点 View 开始循环扩展并填充整个 View 。我已经实现了以下代码，但它并没有循环填充 View 。有什么想法吗？

- (void)viewDidLoad {
[super viewDidLoad];
myView =[[UIView alloc]init];
myView.frame=CGRectMake(self.view.frame.size.width/2,self.view.frame.size.height/2+100, .1, .1);
myView.backgroundColor=[UIColor redColor];
[self.view addSubview:myView];
[self animate];
}

-(void)animate{
[UIView animateWithDuration:1.0
                      delay: 0.0
                    options:UIViewAnimationOptionCurveEaseOut
                 animations:^{
                     [self setRoundedView: myView toDiameter:1000];

                 }
                 completion:nil];
}


-(void)setRoundedView:(UIView *)roundedView toDiameter:(float)newSize;
{
CGPoint saveCenter = roundedView.center;
    CGRect newFrame = CGRectMake(roundedView.frame.origin.x,      roundedView.frame.origin.y, newSize, newSize);
roundedView.frame = newFrame;
roundedView.layer.cornerRadius = newSize / 2.0;
roundedView.center = saveCenter;
}

Answer 1

您可以创建一个带有圆形贝塞尔路径的 CAShape 层，并为路径属性设置动画。

CABasicAnimation* animation = [CABasicAnimation animationWithKeyPath: @"path"];

点击这里了解更多详情:Animating CAShapeLayer size change

如果你不想使用 CAnimation，你可以像这样缩放你的圆形 View :

[UIView animateWithDuration:1.0
                  delay: 0.0
                options:UIViewAnimationOptionCurveEaseOut
             animations:^{
                 myView.transform = CGAffineTransformMakeScale(scaleX,scaleY);

             }
             completion:nil];