swift - 淡入淡出 SKLabelNodes 的最佳方式

Question

我正在开发一款小型 SpriteKit 游戏。

我想在主屏幕上有一个“提示”部分，每次显示不同的提示。

我有一个可行的方法，它是我自己编写的，但它很困惑，我确信有更好的方法可以完成。我希望有人可以向我展示我可能错过(或绕过很长一段路)的方法。

我目前是这样做的:

func createTipsLabels(){
    //create SKLabelNodes
    //add properties to Labels

    //tip1Label... etc
    //tip2Label... etc
    //tip3Label... etc

    //now animate (or pulse) in tips label, one at a time...
    let tSeq = SKAction.sequence([
        SKAction.runBlock(self.fadeTip1In),
        SKAction.waitForDuration(5),
        SKAction.runBlock(self.fadeTip1Out),
        SKAction.waitForDuration(2),
        SKAction.runBlock(self.fadeTip2In),
        SKAction.waitForDuration(5),
        SKAction.runBlock(self.fadeTip2Out),
        SKAction.waitForDuration(2),
        SKAction.runBlock(self.fadeTip3In),
        SKAction.waitForDuration(5),
        SKAction.runBlock(self.fadeTip3Out),
        SKAction.waitForDuration(2),
    ])

    runAction(SKAction.repeatActionForever(tSeq))  //...the repeat forever

}

//put in separate methods to allow to be called in runBlocks above
func fadeTip1In() { tip1Label.alpha = 0; tip1Label.runAction(SKAction.fadeInWithDuration(1)) ;  print("1") }
func fadeTip1Out(){ tip1Label.alpha = 1; tip1Label.runAction(SKAction.fadeOutWithDuration(1));  print("2") }
func fadeTip2In() { tip2Label.alpha = 0; tip2Label.runAction(SKAction.fadeInWithDuration(1)) ;  print("3") }
func fadeTip2Out(){ tip2Label.alpha = 1; tip2Label.runAction(SKAction.fadeOutWithDuration(1));  print("4") }
func fadeTip3In() { tip3Label.alpha = 0; tip3Label.runAction(SKAction.fadeInWithDuration(1)) ;  print("5") }
func fadeTip3Out(){ tip3Label.alpha = 1; tip3Label.runAction(SKAction.fadeOutWithDuration(1));  print("6") }

我该如何优化它？

Answer 1

无需创建多个标签，也无需执行多个操作，只需创建一个包含您要执行的操作的数组，然后遍历它即可。

func createTipsLabels()
{
   let tips = ["1","2","3","4","5"];
   var tipCounter = 0
   {
     didSet
     {
       if (tipCounter >= tips.count)
       {
         tipCounter = 0;
       }
     }
   }
   tipLabel.alpha = 0;
   let tSeq = SKAction.sequence([

        SKAction.runBlock({[unowned self] in self.tipLabel.text = tips[tipCounter]; print(tips[tipCounter]); tipCounter+=1;}),
        SKAction.fadeInWithDuration(1),
        SKAction.waitForDuration(5),
        SKAction.fadeOutWithDuration(1),

        SKAction.waitForDuration(2)

    ])


    tipLabel.runAction(SKAction.repeatActionForever(tSeq))  //...the repeat forever

}