ios - 所有其他手势均失败

Question

在我的容器 Controller 中，有时我必须向 View 添加手势识别器来处理事情。是否有可能使所述 View 上的所有其他手势都失败并仅执行添加的手势？

选项 1:
现在，当检测到新手势时，所有单独的手势都设置为失败，但这样做似乎效率不高。

选项 2:
另一种方法是获取所述 View 的手势数组，并将数组内的所有手势的 enabled 设置为 false。

我想做的是将新手势的委托(delegate)设置到容器 Controller ，并使用其中一种委托(delegate)方法在检测到新手势时使所有其他手势失败。

Answer 1

如果您想删除其他手势识别器并希望保留用户使用的一个手势，那么您可以通过检测该手势的方向来完成，然后您可以删除所有其他手势并保留使用过的手势。

这是完整的工作代码:

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        let swipeRight = UISwipeGestureRecognizer(target: self, action: Selector("rightSwiped:"))
        swipeRight.direction = UISwipeGestureRecognizerDirection.Right
        self.view.addGestureRecognizer(swipeRight)

        let swipeLeft = UISwipeGestureRecognizer(target: self, action: Selector("leftSwiped:"))
        swipeLeft.direction = UISwipeGestureRecognizerDirection.Left
        self.view.addGestureRecognizer(swipeLeft)

        let swipeDown = UISwipeGestureRecognizer(target: self, action: Selector("downSwiped:"))
        swipeDown.direction = UISwipeGestureRecognizerDirection.Down
        self.view.addGestureRecognizer(swipeDown)

        let swipeUp = UISwipeGestureRecognizer(target: self, action: Selector("upSwiped:"))
        swipeUp.direction = UISwipeGestureRecognizerDirection.Up
        self.view.addGestureRecognizer(swipeUp)
    }

    func rightSwiped(recognizer: UISwipeGestureRecognizer)
    {
        println("right swiped ")
        manageGesture(recognizer)

    }

    func manageGesture(recognizer: UISwipeGestureRecognizer) {

        //First detect which gesture is used

        if recognizer.direction == UISwipeGestureRecognizerDirection.Right {
            println("Right")

            if let recognizers = view.gestureRecognizers {
                for recognizer in recognizers {
                    if recognizer.direction == UISwipeGestureRecognizerDirection.Right {
                        println("Called")
                    }else {
                        view.removeGestureRecognizer(recognizer as! UIGestureRecognizer)
                    }
                }
            }

        }else if recognizer.direction == UISwipeGestureRecognizerDirection.Left {
            println("Left")

            if let recognizers = view.gestureRecognizers {
                for recognizer in recognizers {
                    if recognizer.direction == UISwipeGestureRecognizerDirection.Left {
                        println("Called")
                    }else {
                        view.removeGestureRecognizer(recognizer as! UIGestureRecognizer)
                    }
                }
            }
        }else if recognizer.direction == UISwipeGestureRecognizerDirection.Up {
            println("Up")

            if let recognizers = view.gestureRecognizers {
                for recognizer in recognizers {
                    if recognizer.direction == UISwipeGestureRecognizerDirection.Up {
                        println("Called")
                    }else {
                        view.removeGestureRecognizer(recognizer as! UIGestureRecognizer)
                    }
                }
            }
        }else if recognizer.direction == UISwipeGestureRecognizerDirection.Down {
            println("Down")

            if let recognizers = view.gestureRecognizers {
                for recognizer in recognizers {
                    if recognizer.direction == UISwipeGestureRecognizerDirection.Down {
                        println("Called")
                    }else {
                        view.removeGestureRecognizer(recognizer as! UIGestureRecognizer)
                    }
                }
            }
        }

    }

    func leftSwiped(recognizer: UISwipeGestureRecognizer)
    {
        println("left swiped ")
        manageGesture(recognizer)
    }

    func downSwiped(recognizer: UISwipeGestureRecognizer)
    {
        println("down swiped ")
        manageGesture(recognizer)
    }

    func upSwiped(recognizer: UISwipeGestureRecognizer)
    {
        println("Up swiped ")
        manageGesture(recognizer)
    }


}

希望这就是您所需要的。