swift 2.0 分配了哪个图像

Question

我想知道如何检查哪个图像分配给了 SKSpriteNode。

这是我的代码:2月11日更新

import SpriteKit

class GameScene: SKScene, SKPhysicsContactDelegate {

    override func didMoveToView(view: SKView) {
        /* Setup your scene here */

       self.physicsWorld.contactDelegate = self

    }//enddidMoveToView

    override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
       /* Called when a touch begins */
        print("hello")
        var ball = SKSpriteNode()
        for touch in touches {

            let location = touch.locationInNode(self)
            //calls a ball with a randomImgColor
            ball = SKSpriteNode(imageNamed:"ball\(arc4random_uniform(3))")
            ball.xScale = 0.1
            ball.yScale = 0.1
            ball.physicsBody = SKPhysicsBody(circleOfRadius:  ball.size.height / 2.5)
            ball.position = location

            if ball == SKSpriteNode(imageNamed:"ball0") {
                print("the red ball was assigned")
            } else if ball == SKSpriteNode(imageNamed:"ball1") {
                print("the green ball was assigned")
            } else if ball == SKSpriteNode(imageNamed:"ball2") {
                print("the blue ball was assigned")
            }

            self.addChild(ball) 
        }//ends touch
    }//endtouchesBegan


    override func update(currentTime: CFTimeInterval) {
        /* Called before each frame is rendered */
    }


}//end GameScene

Answer 1

我为您提供了一个解决方案，但它可能不是您正在寻找的。由于您通过将随机字符串传递到 SKSpriteNode 来创建图像，因此您可以将该字符串存储在变量中并设置 SKSpriteNotes .name 属性到完全相同的事物，然后检查名称的值。这节省了您创建实例进行检查的麻烦:

override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
        for touch in touches {
            var ball = SKSpriteNode() // in your for loop!
            let location = touch.locationInNode(self)
            let random = "ball\(arc4random_uniform(3))" // <-- notice
            ball = SKSpriteNode(imageNamed:random)
            ball.xScale = 0.1
            ball.yScale = 0.1
            ball.physicsBody = SKPhysicsBody(circleOfRadius:  ball.size.height / 2.5)
            ball.name = random // <-- set name == to your ball type
            ball.position = location

            // safely unwrap ball name
            guard let ballName = ball.name else {
                return
            }
            print(ballName)
            // check ball name
            if ballName == "ball0" {
                print("the red ball was assigned")
            } else if ballName == "ball1" {
                print("the green ball was assigned")
            } else if ballName == "ball2" {
                print("the blue ball was assigned")
            }

            self.addChild(ball)
        }
    }//ends touch    

<小时/>

原帖:

你的条件逻辑混淆了，你缺少一个大括号:

if ball == SKSpriteNode(imageNamed:"ball0") {
    print("the red ball was assigned")
} else if ball == SKSpriteNode(imageNamed:"ball1") {
    print("the green ball was assigned")
} else if ball == SKSpriteNode(imageNamed:"ball2") {
    print("the blue ball was assigned")
}

虽然我不确定你的意图是什么，但我认为你希望 for in 循环中的条件语句正确吗？

for touch in touches {
    let location = touch.locationInNode(self)

    //calls a ball with a randomImgColor
    ball = SKSpriteNode(imageNamed:"ball\(arc4random_uniform(3))")
    ball.position = location

    if ball == SKSpriteNode(imageNamed:"ball0") {
        print("the red ball was assigned")
    } else if ball == SKSpriteNode(imageNamed:"ball1") {
        print("the green ball was assigned")
    } else if ball == SKSpriteNode(imageNamed:"ball2") {
        print("the blue ball was assigned")
    }

    self.addChild(ball) 
}