UIView角落问题[重复]

Question

我有蓝色 UIView，我想要顶角。
这是我的代码：

UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:self.backgroundContentView.bounds byRoundingCorners:(UIRectCornerTopLeft | UIRectCornerTopRight) cornerRadii:CGSizeMake(20.0, 20.0)];
CAShapeLayer *shapeLayer = [[CAShapeLayer alloc] init];
shapeLayer.frame = self.backgroundContentView.bounds;
shapeLayer.path  = path.CGPath;
self.backgroundContentView.layer.mask = shapeLayer;

但我只有左上角。为什么？

Answer 1

使用此代码将内存分配给CALayer

CAShapeLayer *maskLayer = [CAShapeLayer layer];