点击时如何让精灵改变方向？

Question

第一次触摸时，我的播放器开始沿 y 轴向上移动，我的设置如下：

 override func touchesBegan(...) {
if isMovingup == true  {
        let up = SKAction.moveByX(0, y: 900, duration: 9)
         player.runAction(up)
    }
    else {
        let down = SKAction.moveByX(0, y: -900, duration: 9)
        player.runAction(down)
 }
    isMovingup = !isMovingup
    }

但是，当第二次点击节点时，我希望它沿着 y 轴向下移动，但到目前为止，它什么也没做。如有必要，将 post 更多代码。

Answer 1

你需要用player.removeAllActions()停止之前的动作，否则你的动作会继续叠加。

override func touchesBegan(...) {
    player.removeAllActions() //<-- Touching always causes the player to change direction, so lets cancel out the previous action before assigning a new one
    if isMovingup == true  {
        let up = SKAction.moveByX(0, y: 900, duration: 9)
        player.runAction(up)
    }
    else {
        let down = SKAction.moveByX(0, y: -900, duration: 9)
        player.runAction(down)
    }
    isMovingup = !isMovingup
}

Answer 2

看起来你的布尔翻转超出了函数的范围。尝试将行 isMovingup = !isMovingup 移动到最后一个大括号内。

override func touchesBegan(...) {
    if isMovingup {
        let up = SKAction.moveByX(0, y: 900, duration: 9)
        player.runAction(up)
    }
    else {
        let down = SKAction.moveByX(0, y: -900, duration: 9)
        player.runAction(down)
    }
    isMovingup = !isMovingup
}

Answer 3

好像是代码片

isMovingup = !isMovingup

是在函数外定义的，所以它不是运行。将它移到函数内的 else 语句之后，这样每次调用函数时它都会是运行

override func touchesBegan(...) {
    if isMovingup == true  {
        let up = SKAction.moveByX(0, y: 900, duration: 9)
        player.runAction(up)
    }
    else {
        let down = SKAction.moveByX(0, y: -900, duration: 9)
        player.runAction(down)
   }
   isMovingup = !isMovingup
}

点击时如何让精灵改变方向？

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