这是我第一次发布堆栈溢出，如果我做错了，请告诉我。我的任务很简单，我想发送精灵在与网球架/物体接触时随机移动。我需要帮助完成任务的第二部分。谁能帮帮我吗？我对Swift比较陌生，所以请记住这一点。
类ViewController：UIViewController {
@IBOutlet weak var playButton: UIButton!
@IBOutlet weak var tennisRacket: UIImageView!
@IBOutlet weak var moveRacket: UIButton!
@IBOutlet weak var scoreLabel: UILabel!
@IBOutlet weak var scoreText: UILabel!
var tennisScene = SKScene()
var tennisBallSprite = SKSpriteNode(imageNamed: "tennisball")
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
// hide or show elements
playButton.hidden = false
tennisRacket.hidden = true
moveRacket.hidden = true
scoreLabel.hidden = true
scoreText.hidden = true
tennisBallSprite.hidden = true
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func delay(delay:Double, closure:()->()) {
dispatch_after(
dispatch_time(
DISPATCH_TIME_NOW,
Int64(delay * Double(NSEC_PER_SEC))
),
dispatch_get_main_queue(), closure)
}
@IBAction func playPressed(sender: UIButton) {
playButton.hidden = true
tennisRacket.hidden = false
moveRacket.hidden = false
tennisBallSprite.hidden = false
tennisBallSprite.position = CGPointZero
tennisBallSprite.size = CGSize(width: 20, height: 20)
tennisBallSprite.physicsBody?.affectedByGravity = true
tennisBallSprite.physicsBody?.allowsRotation = true
tennisScene.addChild(tennisBallSprite)
}
@IBAction func hitBall(sender: UIButton) {
self.tennisRacket.transform = CGAffineTransformMakeRotation((-15 * CGFloat(M_PI)) / 180.0)
delay(1/5) {
self.tennisRacket.transform = CGAffineTransformIdentity
}
}
}