【代码笔记】将图片处理成圆的

一，效果图。

二，工程图。

三，代码。

ViewController.m

- (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. //初始化界面
 [self addView]; } #pragma -mark -functions
//初始化界面
-(void)addView { UIImageView *imageView=[[UIImageView alloc] initWithFrame:CGRectMake(20, 50, 100, 100)]; imageView.image=[self changeimagetocilce:[UIImage imageNamed:@"1.png"]]; [self.view addSubview:imageView]; } //将图片处理成圆的
-(id)changeimagetocilce:(UIImage*)image { UIImage *finalImage = nil; UIGraphicsBeginImageContext(image.size); { CGContextRef ctx = UIGraphicsGetCurrentContext(); CGAffineTransform trnsfrm = CGAffineTransformConcat(CGAffineTransformIdentity, CGAffineTransformMakeScale(1.0, -1.0)); trnsfrm = CGAffineTransformConcat(trnsfrm, CGAffineTransformMakeTranslation(0.0, image.size.height)); CGContextConcatCTM(ctx, trnsfrm); CGContextBeginPath(ctx); CGContextAddEllipseInRect(ctx, CGRectMake(0.0, 0.0, image.size.width, image.size.height)); CGContextClip(ctx); CGContextDrawImage(ctx, CGRectMake(0.0, 0.0, image.size.width, image.size.height), image.CGImage); finalImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); } return finalImage; }