Gesture透过view传递到上层的view

bottomView上添加了一个手势，bottomView上增加了topView，topView上加了一个button

然后在topView上移动，依然能收到手势对应的方法，在button上移动也能收到手势对应的方法

- (void)viewDidLoad

{

    [super viewDidLoad];

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

    UIView *bottomView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 400)];

    bottomView.backgroundColor = [UIColor greenColor];

    UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(pan:)];

    [bottomView addGestureRecognizer:pan];

    [self.view addSubview:bottomView];

    

    UIView *topView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 200)];

    topView.backgroundColor = [UIColor brownColor];

    topView.userInteractionEnabled = YES;

    [bottomView addSubview:topView];

    

    UIButton *btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];

    btn.frame = CGRectMake(0, 0, 60, 30);

    [btn addTarget:self action:@selector(bbb:) forControlEvents:UIControlEventTouchUpInside];

    [topView addSubview:btn];

}

- (void)pan:(UIPanGestureRecognizer *)panGes

{

    NSLog(@"fan pan ");

}

- (void)bbb:(id)sender

{

    NSLog(@"button press");

}