- (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;

}