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.
? 1 2 3 4 5 6 7class="java plain">UIImageView *imageView = [[UIImageView alloc]initWithFrame:CGRectMake(
100
,
100
,
100
,
100
)];
//只需要设置layer层的两个属性
//设置圆角
imageView.layer.cornerRadius = imageView.frame.size.width /
2
;
//将多余的部分切掉
imageView.layer.masksToBounds = YES;
[self.view addSubview:imageView];
第二种方法:使用贝塞尔曲线UIBezierPath和Core Graphics框架画出一个圆角
? 1 2 3 4 5 6 7 8 9 10 11UIImageView *imageView = [[UIImageView alloc]initWithFrame:CGRectMake(
100
,
100
,
100
,
100
)];
imageView.image = [UIImage imageNamed:@
"1"
];
//开始对imageView进行画图
UIGraphicsBeginImageContextWithOptions(imageView.bounds.size, NO,
1.0
);
//使用贝塞尔曲线画出一个圆形图
[[UIBezierPath bezierPathWithRoundedRect:imageView.bounds cornerRadius:imageView.frame.size.width] addClip];
[imageView drawRect:imageView.bounds];
imageView.image = UIGraphicsGetImageFromCurrentImageContext();
//结束画图
UIGraphicsEndImageContext();
[self.view addSubview:imageView];
第三种方法:使用CAShapeLayer和UIBezierPath设置圆角
#import "ViewController.h" #import <AVFoundation/AVFoundation.h> @interface ViewController () @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(100, 100, 200, 100)]; imageView.image = [UIImage imageNamed:@"1"]; UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:imageView.bounds byRoundingCorners:UIRectCornerBottomLeft | UIRectCornerTopLeft cornerRadii:CGSizeMake(25, 5)]; CAShapeLayer *maskLayer = [[CAShapeLayer alloc]init]; maskLayer.frame = imageView.bounds; maskLayer.path = maskPath.CGPath; imageView.layer.mask = maskLayer; [self.view addSubview:imageView]; }
这三种方法中第三种最好,对内存的消耗最少啊,而且渲染快速。
效果图: