swift - 节点不动

Question

( swift 3)

import SpriteKit
   import GameplayKit

   class GameScene: SKScene {
var object = SKSpriteNode()

override func didMove(to view: SKView) {

    object = self.childNode(withName: "dot") as! SKSpriteNode

}

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {

    for touch in touches {
        let location = touch.location(in: self)
        object.run(SKAction.move(to: location, duration: 0.3))

    }

}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
    for touch in touches {
        let location = touch.location(in: self)

        object.run(SKAction.move(to: location, duration: 0.3))


    }
}

override func update(_ currentTime: TimeInterval) {




   }
}

此代码旨在允许我在场景周围拖动一个“点”，但是......我就是做不到!它不会让步!我在网上看过，但找不到任何东西。我尝试将这段代码粘贴到一个新项目中，它在那里工作，但即使删除和替换我的“点”节点似乎也对我的主项目没有帮助。

那么……有什么想法吗？

Answer 1

Confused 已经说完了您必须了解的关于您的问题的一切。我尝试添加有助于您编写代码的详细信息。首先，当您使用 self.childNode(withName 搜索节点时，您应该使用可选绑定(bind)，这样如果该节点不存在，您的项目就不会崩溃。然后，正如 Confused 所解释的那样，您应该在调用操作之前添加控件，以确保您的操作尚未运行。下面我举个例子:

import SpriteKit
class GameScene: SKScene {
    var object = SKSpriteNode.init(color: .red, size: CGSize(width:100,height:100))
    override func didMove(to view: SKView) {
        if let sprite = self.childNode(withName: "//dot") as? SKSpriteNode {
            object = sprite
        } else { //dot not exist so I draw a red square..
            addChild(object)
        }
        object.position = CGPoint(x:self.frame.midX,y:self.frame.midY)
    }
    func makeMoves(_ destination: CGPoint) {
        if object.action(forKey: "objectMove") == nil {
            object.run(SKAction.move(to: destination, duration: 0.3),withKey:"objectMove")
        }
    }
    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        for touch in touches {
            let location = touch.location(in: self)
            makeMoves(location)
        }
    }
    override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
        for touch in touches {
            let location = touch.location(in: self)
            makeMoves(location)
        }
    }
}

输出: