- (void)viewDidLoad{    [super viewDidLoad];    // Do any additional setup after loading the view.        self.title=@"伸缩式动画";}//点击任何处，弹出动画-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{        UIView *zanView = [[UIView alloc] initWithFrame:CGRectMake(50, 100, 100, 100)];    zanView.backgroundColor = [UIColor redColor];    [self.view addSubview:zanView];        [UIView animateWithDuration:0.3 animations:^{        zanView.transform = CGAffineTransformMakeScale(1.2, 1.2);    } completion:^(BOOL finished) {        [UIView animateWithDuration:0.3 animations:^{            zanView.transform = CGAffineTransformMakeScale(0.9, 0.9);        } completion:^(BOOL finished) {            [UIView animateWithDuration:0.3 animations:^{                zanView.transform = CGAffineTransformMakeScale(1.0, 1.0);            } completion:^(BOOL finished) {                            }];        }];    }];    }