可改变的图像

Question

    Ghost = SKSpriteNode(imageNamed: "Ghost1")
    Ghost.size = CGSize(width: 50, height: 50)
    Ghost.position = CGPoint(x: self.frame.width / 2 - Ghost.frame.width, y: self.frame.height / 2)

    Ghost.physicsBody = SKPhysicsBody(circleOfRadius: Ghost.frame.height / 1.4)
    Ghost.physicsBody?.categoryBitMask = PhysicsCatagory.Ghost
    Ghost.physicsBody?.collisionBitMask = PhysicsCatagory.Ground | PhysicsCatagory.Wall
    Ghost.physicsBody?.contactTestBitMask = PhysicsCatagory.Ground | PhysicsCatagory.Wall | PhysicsCatagory.Score
    Ghost.physicsBody?.affectedByGravity = false
    Ghost.physicsBody?.isDynamic = true

    Ghost.zPosition = 2


    self.addChild(Ghost)

在我的应用程序上，我有一个在屏幕上到处移动的对象，它的名字是“幽灵”。我不知道如何设置一个可以更改代码的按钮

Ghost = SKSpriteNode(imageNamed: "Ghost2")

而不是

Ghost = SKSpriteNode(imageNamed: "Ghost1")

Answer 1

要更改SKSpriteNode的图像，请指定不同的纹理：

Ghost.texture = SKTexture(imageNamed:"Ghost2")

注意:变量名应该使用小写字母，以区别于类名。

一个包含Button和Ghost的示例实现如下图所示，右上角创建了一个红色按钮。注意按钮和重影的声明现在发生在didMoveToView之外，这样以后当用户点击屏幕时就可以引用这些变量。

class ButtonGhostScene: SKScene {
    var button: SKNode! = nil
    var ghost: SKSpriteNode! = nil

    override func didMove(to view: SKView) {
        button = SKSpriteNode(color: SKColor.redColor(), size: CGSize(width: 100, height: 44))
        button.position = CGPoint(x:self.size.width, y:self.size.height)

        ghost = SKSpriteNode(imageNamed: "Ghost1")
        ghost.size = CGSize(width: 50, height: 50)
        ghost.position = CGPoint(x: self.frame.width / 2 - Ghost.frame.width, y: self.frame.height / 2)
        ghost.physicsBody = SKPhysicsBody(circleOfRadius: Ghost.frame.height / 1.4)
        ghost.physicsBody?.categoryBitMask = PhysicsCatagory.Ghost
        ghost.physicsBody?.collisionBitMask = PhysicsCatagory.Ground | PhysicsCatagory.Wall
        ghost.physicsBody?.contactTestBitMask = PhysicsCatagory.Ground | PhysicsCatagory.Wall | PhysicsCatagory.Score
        ghost.physicsBody?.affectedByGravity = false
        ghost.physicsBody?.isDynamic = true
        ghost.zPosition = 2

        self.addChild(ghost)
        self.addChild(button)
    }

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        // Loop over all the touches in this event
        for touch: AnyObject in touches {
            // Get the location of the touch in this scene
            let location = touch.location(in: self)
            // Check if the location of the touch is within the button's bounds
            if button.containsPoint(location) {
                ghost.texture = SKTexture(imageNamed:"Ghost2")
            }
        }
    }
}

当用户点击屏幕时，将执行touchesBegan，并进行检查以查看用户是否点击了按钮。