界面视图。为什么在其父范围之外的子视图没有收到触摸？

Question

我有一个简单的 - 微不足道的 - UIView 父/子层次结构。一位家长（UIView）。一个孩子（UIButton）。父母的界限比它的孩子的界限小，因此孩子的一部分延伸到其父母的边界框之外。

问题是：父 bbox 之外的子部分不接收到触摸。只有在父母的 bbox 内点击才允许子按钮接收触摸。

有人可以建议修复/解决方法吗？

更新

对于那些关注这个问题的人，这是我根据@Bastian 最优秀的答案实施的解决方案：

- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event {

    BOOL isInside = [super pointInside:point withEvent:event];

    // identify the button view subclass
    UIButton *b = (UIButton *)[self viewWithTag:3232];
    CGPoint inButtonSpace = [self convertPoint:point toView:b];

    BOOL isInsideButton = [b pointInside:inButtonSpace withEvent:nil];

    if (isInsideButton) {

        return isInsideButton;

    } // if (YES == isInsideButton)

    return isInside;        
}

Answer 1

问题在于响应者链。当您触摸显示屏时，它会从父母向下传递给孩子。

所以..当你触摸屏幕时，父母会看到触摸超出了它自己的界限，所以孩子们甚至不会问。

执行此操作的函数是 hitTest。如果你有自己的 UIView 类，你可以覆盖它并自己返回按钮。

- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event

Answer 2

根据Apple’s own documentation，我发现的最简单和最可靠的方法是在剪辑视图的超类中覆盖hitTest:withEvent:，如下所示：

- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {

    // Convert the point to the target view's coordinate system.
    // The target view isn't necessarily the immediate subview
    CGPoint pointForTargetView = [self.targetView convertPoint:point fromView:self];

    if (CGRectContainsPoint(self.targetView.bounds, pointForTargetView)) {

        // The target view may have its view hierarchy,
        // so call its hitTest method to return the right hit-test view
        return [self.targetView hitTest:pointForTargetView withEvent:event];
    }

    return [super hitTest:point withEvent:event];
}

Answer 3

前提条件：

UIView（命名为容器）中有一个 UIButton（命名为 button1），并且 button1 部分位于容器边界之外。

问题：

button1容器外的部分不会响应点击。

解决方案：

从 UIView 子类化您的容器：

class Container: UIView {
    override func pointInside(point: CGPoint, withEvent event: UIEvent?) -> Bool {

        let closeButton = viewWithTag(10086) as! UIButton  //<-- note the tag value
        if closeButton.pointInside(convertPoint(point, toView: closeButton), withEvent: event) {
            return true
        }
        return super.pointInside(point, withEvent: event)
    }
}

别忘了给你的按钮1一个标签10086

Answer 4

• @dugla，谢谢你的提问！
• @Bastian 和 @laoyur，感谢您的回答！

斯威夫特 4

override func point(inside point: CGPoint, with event: UIEvent?) -> Bool {

    if yourChildView.point(inside: convert(point, to: yourChildView), with: event) {
        return true
    }

    return super.point(inside: point, with: event)
}

Answer 5

我手头也有同样的问题。您只需要覆盖：

-(BOOL) pointInside:(CGPoint)point withEvent:(UIEvent *)event

这是一个自定义 UIView 子类的工作代码，该子类仅为其越界子类创建可点击。

@implementation ARQViewToRightmost

// We should not need to override this one !!!
/*-(UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
    if ([self isInside:point])
        return self;
    return nil;
}*/

-(BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event
{
    if ([self isInside:point])
        return YES; // That answer will make hitTest continue recursively probing the view's subviews for hit
    return NO;
}

// Check to see if the point is within the bounds of the view. We've extended the bounds to the max right
// Make sure you do not have any other sibling UIViews to the right of this one as they will never receive events
- (BOOL) isInside:(CGPoint)point
{
    CGFloat maxWidth = CGFLOAT_MAX;
    CGRect rect = CGRectMake(0, 0, maxWidth, self.frame.size.height);
    if (CGRectContainsPoint(rect, point))
        return YES;
    return NO;
}

@end