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如何解决tableView(UIScrollView)与其sub

2016-04-24  本文已影响3614人  KevinTing

最近做的一个项目,基本情况可以这样描述:一个tableView,每个cell占据一个页面,paging enabled属性设置为YES,那么上下滑动会翻页,每个cell都有一个立方体:

手势冲突1.gif

然后我希望每个cell都可以在手指左右滑的时候,立方体能够旋转!你会想到加一个手势不就行了么,是的,我也是这么做的:

        UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePan:)];
        pan.delegate = self;
        [self.contentView addGestureRecognizer:pan];

- (void)handlePan:(UIPanGestureRecognizer *)pan
{
    CGPoint point = [pan translationInView:self];
    switch (pan.state)
    {
        case UIGestureRecognizerStateBegan:
            self.prePoint = point;
            break;
            
        case UIGestureRecognizerStateChanged:
            [self changeCubeWithPoint:point prePoint:self.prePoint screenSize:self.screenSize];
            self.prePoint = point;
            break;
            
        default:
            break;
    }
}

但是你很快会发现,你的cell中的立方体确实在转动,但是不能上下翻页了。很显然是UIPanGestureRecognizer和scrollView的滑动手势冲突了,解决办法是设置UIPanGestureRecognizer的代理UIGestureRecognizerDelegate,并实现代理方法:

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
    return YES;
}

-(BOOL)gestureRecognizer(UIGestureRecognizer*)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer方法的含义是该手势能否与其它手势一起被识别,如果按照上面这样写,你会发现确实既可以滑动又可以转立方体了,但是滑动立方体的时候,你会很容易就误翻页了,tableView太不听话了。真正希望的效果是在横向滑动的时候,立方体转动但是tableView别乱动,快速上下滑的时候tableView再翻页!把上面的方法改成下面的:

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
    if ([gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]])
    {
        switch (gestureRecognizer.state)
        {
            case UIGestureRecognizerStateBegan:
            {
                UIPanGestureRecognizer *pan = (UIPanGestureRecognizer *)gestureRecognizer;
                CGPoint velocity = [pan velocityInView:self];
                CGFloat Vx = fabs(velocity.x);
                CGFloat Vy = fabs(velocity.y);
                
                return !(Vx > Vy - 50.0 || Vy < 400.0 || Vx > 500.0);
            }
                break;
                
            case UIGestureRecognizerStateChanged:
                return NO;
                break;
                
            default:
                break;
        }
    }
    
    return YES;
}

意思就是手势开始的时候,如果发现横向滑动速度Vx比较大的时候,不要去滑动tableView了,如果UIPanGestureRecognizer手势开始了(UIGestureRecognizerStateChanged),也不要去滑动了,只有当开始的时候上下滑速度Vy比较大的时候,才去滑动tableView,达到了我们要的效果:


手势冲突2.gif
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