如何检测用户何时在特定节点上向特定方向滑动？

Question

我的屏幕顶部有 6 个不同的彩色圆圈落下。对于每个节点，您应该朝不同的方向滑动以得分（红色圆圈；向上滑动，蓝色圆圈；向下滑动等），但是如果用户向与分配给该特定节点的方向不同的方向滑动，它结束了游戏。

我对滑动手势非常不熟悉，所以我没有代码，但非常感谢帮助。

我如何生成我的节点：

   func array() {
    let colorCount = 5
    let index=Int(arc4random_uniform(UInt32(colorCount)))
    let colors = SKSpriteNode(imageNamed: "Color\(index+1)")
    colors.size = CGSizeMake(130, 130)
    colors.position = CGPointMake(size.width / 2, 650)
    addChild(colors)
    colors.runAction(
        SKAction.moveByX(0, y: -1600,
            duration: NSTimeInterval(8.5)))
     }

只要落到场景底部以下，它们就会从场景中移除。

Answer 1

您可以像这样添加手势识别器：

class GameScene: SKScene {

    override func didMoveToView(view: SKView) {

        /* Setup your scene here */

        let swipeRight:UISwipeGestureRecognizer = UISwipeGestureRecognizer(target: self, action: Selector("swipedRight:"))
        swipeRight.direction = .Right
        view.addGestureRecognizer(swipeRight)
    }

    func swipedRight(sender:UISwipeGestureRecognizer){
        print("swiped right")
    }
}

其他方向也一样。因此，当您生成一个节点时，您可以设置一个变量来存储当前节点的类型（或颜色），并基于该变量检查用户是否向正确的方向滑动。

提示：

请记住，如果每次加载场景时都添加手势识别器，则可能运行出现内存问题。这可能会发生，因为识别器被添加到视图而不是场景，所以无论场景是否被释放，识别器都会保持活动状态。阅读更多 .

编辑：

这是一个可行的示例，它与您当前的实现略有不同，但总的来说，它做的事情是一样的。您可以复制并粘贴以查看其工作原理。它应该让您了解可以在哪些方向上解决问题，例如：

如何跟踪当前节点的颜色
如何创建SKSpriteNode的子类
如何在节点结束时移除屏幕

可能还有更多（比如如何在分数增加时自动更新标签）

enum Color:UInt32 {

    case Red            // 0 - texture should be Color0@2x.png
    case Blue           // 1 - texture should be Color1@2x.png
    //case Green        // 2 - texture should be Color2@2x.png
    //case Yellow       // 3 - texture should be Color3@2x.png
    case NumberOfColors 
}

class Circle:SKSpriteNode {

    let textureColor:Color

    //Initialize a circle with color and size
    init(textureColor:Color, size:CGSize){

        self.textureColor = textureColor
        super.init(texture: SKTexture(imageNamed: "Color\(textureColor.rawValue)"), color:.clearColor(), size: size)
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

}

class GameScene: SKScene {

    let label = SKLabelNode(fontNamed: "ArialMT")

    var score: Int = 0 {
        didSet {
            label.text = "Score: \(score)"
        }
    }

    var currentCircle:Circle?

    func spawnRandomCircle() {

        //Randomize a circle. If you fail to randomize index correctly, default circle will be blue.
        let index = arc4random_uniform(Color.NumberOfColors.rawValue) 
        let circle = Circle(textureColor: Color(rawValue: index) ?? Color.Blue, size: CGSize(width: 50, height: 50))
        circle.position = CGPointMake(size.width / 2, 650)
        addChild(circle)

        //Move circle (and remove it, if end-up offscreen)
        let move = SKAction.moveByX(0, y: -1600, duration: NSTimeInterval(8.5))
        let moveAndRemove = SKAction.sequence([move, SKAction.removeFromParent()])
        circle.runAction(moveAndRemove, withKey:  "moving")

        //Update currentCircle
        currentCircle = circle
    }

    override func didMoveToView(view: SKView) {

        //Setup score label
        addChild(label)
        label.position = CGPoint(x: frame.minX+50, y: frame.maxY-50) //Put a score label in top left corner
        label.horizontalAlignmentMode = SKLabelHorizontalAlignmentMode.Left
        label.text = String(score)

        //Create gesture recognizers
        let swipeUp:UISwipeGestureRecognizer = UISwipeGestureRecognizer(target: self, action: Selector("swipedUp:"))
        swipeUp.direction = .Up
        view.addGestureRecognizer(swipeUp)

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

        //Spawn first circle
        spawnRandomCircle()
    }

    //This method accepts the Color associated with a certian swipe direction 
    //eg. if Swipe Up is detected, Red color will be passed ...
    func validateSwipe(color:Color){

        if let circle = currentCircle {

            circle.removeFromParent()
            if circle.textureColor == color {++score} else {--score}
            spawnRandomCircle()
        }

    }

    func swipedUp(sender:UISwipeGestureRecognizer){
         validateSwipe(Color.Red) //Red circle - Swipe Up
    }
    func swipedDown(sender:UISwipeGestureRecognizer){
         validateSwipe(Color.Blue) //Blue circle - Swipe Down
    }
}

这可以通过许多不同的方式完成，如果您有任何问题，请随时提出...

如何检测用户何时在特定节点上向特定方向滑动？

How do I detect when a user swipes in a certain direction on a specific node?

uiswipegesturerecognizer

sprite-kit

swift