iOS

    UIImage * image = [UIImage imageNamed:@"1"];    //方式一： 设置layer属性    UIImageView *imageView1 = [[UIImageView alloc ] initWithFrame:CGRectMake(100, 100, 100, 100)];    [imageView1 setImage:image];    //设置圆角大小    imageView1.layer.cornerRadius = 20;    //masksToBounds 默认是NO，需要设置成YES，将视图的图层上的子图层超出部分截取掉。    imageView1.layer.masksToBounds = YES;    [self.view addSubview:imageView1];    //方法二：使用贝塞尔曲线UIBezierPath和Core Graphics框架画出一个圆角    UIImageView *imageView2 = [[UIImageView alloc] initWithFrame:CGRectMake(100, 220, 100, 100)];    [imageView2 setImage:image];    UIGraphicsBeginImageContextWithOptions(imageView2.bounds.size, NO, [UIScreen mainScreen].scale);    [[UIBezierPath bezierPathWithRoundedRect:imageView2.bounds cornerRadius:20] addClip];    [imageView2 drawRect:imageView2.bounds];    imageView2.image = UIGraphicsGetImageFromCurrentImageContext();    UIGraphicsEndImageContext();    [self.view addSubview:imageView2];    //方法三：使用CAShapeLayer和UIBezierPath设置圆角    UIImageView *imageView3 = [[UIImageView alloc] initWithFrame:CGRectMake(100, 330, 100, 100)];    [imageView3 setImage:image];    UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:imageView3.bounds byRoundingCorners:UIRectCornerAllCorners cornerRadii:CGSizeMake(20,20)];    CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];    maskLayer.frame = imageView3.bounds;    maskLayer.path = maskPath.CGPath;    imageView3.layer.mask = maskLayer;    [self.view addSubview:imageView3];