手势之 shouldReceive touch
2022-06-15 本文已影响0人
大刘
Created by 大刘 liuxing8807@126.com
在实际做项目中遇到一个小问题,即往父视图中添加UITapGestureRecognizer,即使点击了子视图,手势也会响应
gesture.png如上,手势加在红色视图上,绿色视图添加到了红色视图上,点击绿色的子视图,触发了tap方法:
import UIKit
class ViewController: UIViewController {
var redView: UIView = UIView()
var greenView: UIView = UIView()
override func viewDidLoad() {
super.viewDidLoad()
// red view
redView.frame = self.view.bounds
redView.backgroundColor = UIColor.red
let tap: UITapGestureRecognizer = UITapGestureRecognizer.init(target: self, action: #selector(self.tap))
redView.addGestureRecognizer(tap)
self.view.addSubview(redView)
// green view on red view
greenView.frame = CGRect.init(x: 0.0, y: self.view.bounds.size.height/2.0, width: self.view.bounds.size.width, height: self.view.bounds.size.height/2.0)
greenView.backgroundColor = UIColor.green
greenView.isUserInteractionEnabled = true
redView.addSubview(greenView);
}
@objc
func tap() {
print("YES")
}
}
参考:stackoverflow, 需要实现代理方法 UIGestureRecognizerDelegate:
import UIKit
class ViewController: UIViewController, UIGestureRecognizerDelegate {
var redView: UIView = UIView()
var greenView: UIView = UIView()
override func viewDidLoad() {
super.viewDidLoad()
// red view
redView.frame = self.view.bounds
redView.backgroundColor = UIColor.red
let tap: UITapGestureRecognizer = UITapGestureRecognizer.init(target: self, action: #selector(self.tap))
tap.delegate = self; // 添加代理方法
redView.addGestureRecognizer(tap)
self.view.addSubview(redView)
// green view on red view
greenView.frame = CGRect.init(x: 0.0, y: self.view.bounds.size.height/2.0, width: self.view.bounds.size.width, height: self.view.bounds.size.height/2.0)
greenView.backgroundColor = UIColor.green
redView.addSubview(greenView);
}
@objc
func tap() {
print("YES")
}
//MARK: -
//实现代理方法
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 {
// 假如触摸在绿色视图上:
// touchedView: 触摸的视图,绿色视图
// gestureView: 添加手势的视图,红色视图
print("click green view")
return false
}
print("click red view")
return true
}
}