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标题: ios - 滑动在 uiscrollview 中无法正常工作 [打印本页]

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作者: 菜鸟教程小白    时间: 2022-12-13 06:53
标题: ios - 滑动在 uiscrollview 中无法正常工作

我有一个名为 templateView 的 UISrollView。我必须向它添加一个滑动手势，以允许用户向左/向右滑动以查看另一个模板。问题是大多数时候用户不能轻松滑动，因为 View 向下/向上滚动而不是滑动到另一个 View 。他的手指需要严格水平对齐才能滑动到另一个页面，从用户体验的角度来看这是 Not Acceptable 。

知道如何处理这种情况吗？有没有办法实现检测滑动手势的角度？或者，有没有办法将其作为自定义手势来检测具有特定角度的斜线？

提前致谢。

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Best Answer-推荐答案

尝试实现 UIGestureRecognizer Delegate 方法。当gestureRecognizer 或otherGestureRecognizer 对手势的识别会阻止其他手势识别器识别其手势时，将调用此方法。请注意，返回 YES 保证允许同时识别。

- (BOOL)gestureRecognizerUIGestureRecognizer *)gestureRecognizer 
    shouldRecognizeSimultaneouslyWithGestureRecognizerUIGestureRecognizer *)otherGestureRecognizer  
    {
        return YES;
    }

引用: UIGestureRecognizer Protocol

在初始化滑动手势时不要忘记分配委托(delegate)。

更新 1 创建自己的手势

您始终可以继承 UIGestureRecognizer 类并实现 touchesBegan、touchesMoved、touchesEnded 方法 - 根据您自己的手动管理手势状态需要。

我发布了一些实现自定义 EdgeGestureRecognizer 的示例代码，以便您更好地理解。

- (void)touchesBeganNSSet *)touches withEventUIEvent *)event
{
    [super touchesBegan:touches withEvent:event];
    UITouch *touch = touches.anyObject;
    CGPoint location = [touches.anyObject locationInView:self.view];

    // if not single finger, then fail

    if ([touches count] != 1)
    {
        self.state = UIGestureRecognizerStateFailed;
        return;
    }
   //put here some logics for your case. For instance, you can register
   //here your first touch location, it will help
   //you to calculate the angle after.
}

- (void)touchesMovedNSSet *)touches withEventUIEvent *)event
{
    [super touchesMoved:touches withEvent:event];

    if (self.state == UIGestureRecognizerStateFailed) return;

    UITouch *touch = touches.anyObject;
    self.previousPoint = self.currentPoint;
    self.previousPointTime = self.currentPointTime;
    self.currentPoint = [touch locationInView:self.view];
    self.currentPointTime = touch.timestamp;

    if (self.state == UIGestureRecognizerStatePossible)
    {
        CGPoint translate = CGPointMake(self.currentPoint.x - self.startPoint.x, self.currentPoint.y - self.startPoint.y);

        // see if we've moved the necessary minimum distance

        if (sqrt(translate.x * translate.x + translate.y * translate.y) >= self.minimumRecognitionDistance)
        {
            // recognize if the angle is roughly horizontal, otherwise fail

            double angle = atan2(translate.y, translate.x);

            if ([self isAngleCloseEnough:angle])
                self.state = UIGestureRecognizerStateBegan;
            else
                self.state = UIGestureRecognizerStateFailed;
        }
    }
    else if (self.state == UIGestureRecognizerStateBegan)
    {
        self.state = UIGestureRecognizerStateChanged;
    }
}

关于ios - 滑动在 uiscrollview 中无法正常工作，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/22426447/

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