第一种方法:通过设置layer的属性
最简单的一种,但是很影响性能,一般在正常的开发中使用很少.
lable.clipsToBounds = YES;（耗内存）
lable.layer.cornerRadius = 50;
第二种方法:通过UIGraphics和贝塞尔曲线进行绘制
UIImageView *imageView = [[UIImageView alloc]initWithFrame:CGRectMake(100, 400, 100, 100)];
imageView.image = [UIImage imageNamed:@"ask"];
imageView.image = [self imageWithCornerRadius:50 withImageView:imageView];
[self.view addSubview:imageView];
- (UIImage *)imageWithCornerRadius:(CGFloat)radius withImageView:(UIImageView *)imageView{
CGRect rect = (CGRect){0.f, 0.f, imageView.frame.size};
UIGraphicsBeginImageContextWithOptions(imageView.frame.size, NO, UIScreen.mainScreen.scale);
CGContextAddPath(UIGraphicsGetCurrentContext(),[UIBezierPath bezierPathWithRoundedRect:rect cornerRadius:radius].CGPath);
CGContextClip(UIGraphicsGetCurrentContext());
[imageView.image drawInRect:rect];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
第三种方法:使用CAShapeLayer和UIBezierPath设置圆角
UIImageView *imageView = [[UIImageView alloc]initWithFrame:CGRectMake(100, 100, 100, 100)];
imageView.image = [UIImage imageNamed:@"1"];
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:imageView.bounds byRoundingCorners:UIRectCornerAllCorners cornerRadii:imageView.bounds.size];
CAShapeLayer *maskLayer = [[CAShapeLayer alloc]init];
//设置大小
maskLayer.frame = imageView.bounds;
//设置图形样子
maskLayer.path = maskPath.CGPath;
imageView.layer.mask = maskLayer;
[self.view addSubview:imageView];
