ios - 如何只用笔画画圆

Question

我只想用描边画圆，下面的代码画得很好，但它填满了圆。

我不想让它被填满。请帮助我

    self.circleView = [[UIView alloc] initWithFrame:CGRectMake(10,20,20,20)];
    circleView.alpha = 0.5;
    self.circleView.layer.cornerRadius = 50;
    self.circleView.backgroundColor = [UIColor whiteColor];

Answer 1

改变

self.circleView.backgroundColor = [UIColor whiteColor];

到

self.circleView.backgroundColor = [UIColor clearColor];

并为边框(描边)添加

self.circleView.layer.borderColor = [[UIColor redColor] CGColor];
self.circleView.layer.borderWidth = 1;