我需要实现一个功能时,我加倍的self.view龙头(的观点,将调用一些代码UIViewCotroller
)。 但是,我对这个观点的其他UI对象,我不希望任何识别对象附加到所有这些问题。 我发现下面如何使我的看法手势这种方法,我知道它是如何工作的。 现在我在盘口选择哪种方式对创造这个识别器忽略子视图的前面。 有任何想法吗? 谢谢。
UITapGestureRecognizer *doubleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleDoubleTap:)];
[doubleTap setNumberOfTapsRequired:2];
[self.view addGestureRecognizer:doubleTap];
Answer 1:
你应该采取UIGestureRecognizerDelegate
内部协议self
对象,并调用下面的方法来检查视图。 在此方法中,检查你的看法对touch.view
并返回相应的布尔(是/否)。 事情是这样的:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
{
if ([touch.view isDescendantOfView:yourSubView]) {
return NO;
}
return YES;
}
编辑:请,还要检查@伊恩的回答!
Answer 2:
另一种方法是只比较如果触摸的观点是举手投足查看,因为后人将无法通过的情况。 一个好的,简单的一行:
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
return touch.view == gestureRecognizer.view
}
Answer 3:
而对于斯威夫特变种:
func gestureRecognizer(gestureRecognizer: UIGestureRecognizer, shouldReceiveTouch touch: UITouch) -> Bool {
if touch.view.isDescendantOfView(yourSubView){
return false
}
return true
}
提提, isDescendantOfView
返回一个Boolean
值,它指示接收器是否是到该视图的给定视图的或相同的子视图。
Answer 4:
完整的迅速解决(委托必须实现,并且识别(一个或多个)设置):
class MyViewController: UIViewController UIGestureRecognizerDelegate {
override func viewDidLoad() {
let doubleTapRecognizer = UITapGestureRecognizer(target: self, action: #selector(onBaseTapOnly))
doubleTapRecognizer.numberOfTapsRequired = 2
doubleTapRecognizer.delegate = self
self.view.addGestureRecognizer(doubleTapRecognizer)
}
func gestureRecognizer(gestureRecognizer: UIGestureRecognizer, shouldReceiveTouch touch: UITouch) -> Bool {
if touch.view.isDescendantOfView(self.view){
return false
}
return true
}
func onBaseTapOnly(sender: UITapGestureRecognizer) {
if sender.state == .Ended {
//react to tap
}
}
}
Answer 5:
随着iOS的11和雨燕4.2, UIGestureRecognizerDelegate
有一个名为方法gestureRecognizer(_:shouldReceive:)
。 gestureRecognizer(_:shouldReceive:)
有以下声明:
要求委托,如果一个手势识别应接收代表触摸的对象。
optional func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool
下面的完整代码显示了一个可能的实现gestureRecognizer(_:shouldReceive:)
。 与此代码,在的子视图的抽头ViewController
的视图(包括imageView
)不会触发printHello(_:)
方法。
import UIKit
class ViewController: UIViewController, UIGestureRecognizerDelegate {
override func viewDidLoad() {
super.viewDidLoad()
let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(printHello))
tapGestureRecognizer.delegate = self
view.addGestureRecognizer(tapGestureRecognizer)
let imageView = UIImageView(image: UIImage(named: "icon")!)
imageView.frame = CGRect(x: 50, y: 50, width: 100, height: 100)
view.addSubview(imageView)
// ⚠️ Enable user interaction for imageView so that it can participate to touch events.
// Otherwise, taps on imageView will be forwarded to its superview and managed by it.
imageView.isUserInteractionEnabled = true
}
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
// Prevent subviews of a specific view to send touch events to the view's gesture recognizers.
if let touchedView = touch.view, let gestureView = gestureRecognizer.view, touchedView.isDescendant(of: gestureView), touchedView !== gestureView {
return false
}
return true
}
@objc func printHello(_ sender: UITapGestureRecognizer) {
print("Hello")
}
}
另一种实施gestureRecognizer(_:shouldReceive:)
可以是:
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
return gestureRecognizer.view === touch.view
}
但是请注意,这种替代代码不检查touch.view
是一个子视图gestureRecognizer.view
。
Answer 6:
变体使用CGPoint你摸(SWIFT 4.0)
class MyViewController: UIViewController, UIGestureRecognizerDelegate {
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
// Get the location in CGPoint
let location = touch.location(in: nil)
// Check if location is inside the view to avoid
if viewToAvoid.frame.contains(location) {
return false
}
return true
}
}
Answer 7:
清除斯威夫特方式
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
return touch.view == self.view
}
Answer 8:
需要注意的是gestureRecognizer API已更改为:
gestureRecognizer(_:shouldReceive :)
要特别注意,第一个参数的外部标签下划线(跳跃)指标。
使用许多的上面提供的示例,我没有接收到该事件。 下面是一个对于斯威夫特(3+)的当前版本工作的例子。
public func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
var shouldReceive = false
if let clickedView = touch.view {
if clickedView == self.view {
shouldReceive = true;
}
}
return shouldReceive
}
Answer 9:
再加上上述解决方案,不要忘记检查User Interaction Enabled
的子视图。
Answer 10:
斯威夫特4:
touch.view
现在是可选的,因此基于@安东尼的回答:
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
if let touchedView = touch.view, touchedView.isDescendant(of: deductibleBackgroundView) {
return false
}
return true
}
Answer 11:
我不得不防止孩子视图的姿态。 只有工作的事情是让并保持第一视图和防止全部的未来看法的姿态:
var gestureView: UIView? = nil
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
if (gestureView == nil || gestureView == touch.view){
gestureView = touch.view
return true
}
return false
}
文章来源: UITapGestureRecognizer tap on self.view but ignore subviews