swift - 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")
    }
}

对其他方向做同样的事情。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，则可能会遇到内存问题。这可能会发生，因为识别器被添加到 View 而不是场景，所以无论场景是否被释放，识别器都会保持事件状态。阅读更多 here .

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
• 如何在节点离开屏幕时移除节点

• 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...