序言
最近的需求中有个UIView需要设置左上角和右上角为圆角，其余两个为直角，一开始用的是重写drawRect，然后用绘图重绘每个角的样子，计算起来还是麻烦.
后来发现了下面的方法：
- (void)drawLeftTopCircleCorner {
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];
view.center = CGPointMake(self.view.bounds.size.width * 0.25, self.view.bounds.size.height * 0.25);
view.backgroundColor = [UIColor redColor];
view.layer.masksToBounds = YES;
//这里设置需要绘制的圆角
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:view.bounds
byRoundingCorners:UIRectCornerTopLeft//左上角
cornerRadii:CGSizeMake(25, 25)];//设置圆角大小，弧度为3
CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
maskLayer.frame = view.bounds;
maskLayer.path = maskPath.CGPath;
view.layer.mask = maskLayer;
[self.view addSubview:view];
}
效果图
circleCorner.png
通过这几个枚举值判断画哪个圆角
typedef NS_OPTIONS(NSUInteger, UIRectCorner) {
UIRectCornerTopLeft = 1 << 0,
UIRectCornerTopRight = 1 << 1,
UIRectCornerBottomLeft = 1 << 2,
UIRectCornerBottomRight = 1 << 3,
UIRectCornerAllCorners = ~0UL
};
项目连接地址
本文参考iOS UIView设置少于四个的圆角,感谢该作者
