Question

我有一个UITableViewCell类，我想检测滑动事件（删除），以隐藏drawRect中绘制的一些图形

首先我在单元格中添加了UISwipeGestureRecognice：

// Init swipe gesture recognizer
self.swipeRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipeCell:)];
self.swipeRecognizer.direction = UISwipeGestureRecognizerDirectionLeft | UISwipeGestureRecognizerDirectionRight;
self.swipeRecognizer.delegate = self;
[self.contentView addGestureRecognizer:self.swipeRecognizer];

我实现了一个方法来对滑动事件作出反应：

- (void)swipeCell:(UISwipeGestureRecognizer *)recognizer
{
    switch (recognizer.state) {
        case UIGestureRecognizerStateBegan:
            self.swipeStartPoint = [recognizer locationInView:self.backgroundView];
            BaseLogDebug(INFO, @"Swipe Began at %@", NSStringFromCGPoint(self.swipeStartPoint));
            break;
        case UIGestureRecognizerStateChanged: {
            CGPoint currentPoint = [recognizer locationInView:self.backgroundView];
            CGFloat deltaX = currentPoint.x - self.swipeStartPoint.x;
            BaseLogDebug(INFO, @"Swipe Moved %f", deltaX);
        }
            break;
        case UIGestureRecognizerStateEnded:
            BaseLogDebug(INFO, @"Swipe Ended");
            break;
        case UIGestureRecognizerStateCancelled:
            BaseLogDebug(INFO, @"Swipe Cancelled");
            break;
        default:
            break;
    }
}

为了允许同时手势识别器，我实现了以下方法：

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

手势识别识别的唯一状态是状态UIGestureRecognizerStateEnded。我的代码出了什么问题？

Answer 1

来自UIGestureRecognizer Class Reference docs：

离散手势的识别器从UIGestureRecognizerStatePossible转换为UIGestureRecognizerStateFailed或UIGestureRecognizerStateRecognized。

和

手势识别器识别离散事件，例如点击或滑动，但不报告手势内的更改。换句话说，离散手势不会通过“开始”和“已更改”状态进行转换，也不会失败或被取消。

UISwipeGestureRecognizer是一个离散的手势。如果您想要连续（但相似）的手势，请改用UIPanGestureRecognizer。

如何使用UISwipeGestureRecognizer检测UITableViewCell中的滑动事件

1 个答案: