@interface ViewController ()

@property (nonatomic,strong)UIImageView *topImageView;

@property(nonatomic,strong)UIImageView *bottomImageView;

@end

@implementation ViewController

- (void)viewDidLoad {

    [super viewDidLoad];

    // Do any additional setup after loading the view, typically from a nib.

    UILabel *label=[[UILabel alloc]initWithFrame:CGRectMake(100, 300, 100, 30)];

    label.textColor=[UIColor redColor];

    label.textAlignment=NSTextAlignmentCenter;

    label.text=@"你看到我了" ;

    [self.view addSubview:label];

    UIImage *imageTop=[UIImage imageNamed:@"1111.jpg"];

    //根据创建的image 进行区域裁剪（关键代码）

    CGImageRef refTopImg=CGImageCreateWithImageInRect(imageTop.CGImage, CGRectMake(0, 0, imageTop.size.width, imageTop.size.height/2));

   _topImageView=[[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 375, 667/2)];

    _topImageView.image=[UIImage imageWithCGImage:refTopImg];

    [self.view addSubview:_topImageView];

    CGImageRef refBottomImg=CGImageCreateWithImageInRect(imageTop.CGImage, CGRectMake(0, imageTop.size.height/2, imageTop.size.width, imageTop.size.height/2));

    _bottomImageView=[[UIImageView alloc]initWithFrame:CGRectMake(0, 667/2, 375, 667/2)];

    _bottomImageView.image=[UIImage imageWithCGImage:refBottomImg];

    [self.view addSubview:_bottomImageView];

}

-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event

{

    [UIView animateWithDuration:1 animations:^{

        _topImageView.frame=CGRectMake(0, -667/2, 375, 667/2);

        _bottomImageView.frame=CGRectMake(0, 667, 375, 667/2);

    }];

}

图片分离--分成两片