Question

我确信这很简单。但我不确定发生了什么。我快速休息了一下，然后用Swift三回到它。

我希望点击播放按钮时isPlaying为真，我currentLineup[0]中的人更新了他们的值。他们在调用函数时似乎做了什么。但是，当我致电currentLieneup[0][0]时，值似乎又回到isPlaying: false, timeCameOn: 0，如日志所示？

我有以下内容：

var currentLineup: [[Player]] = []

    @IBAction func playPause(_ sender: UIButton) {
    // change icon to play or pause
    isPlaying = isPlaying ? false : true
    // set player.timeCameOn to current time or back to 0
    updatePlayerGameStartTime(gameInProgress: isPlaying)
    print(currentLineup[0][0])
}

    // When play button pressed, make sure players timeCameOn updated
func updatePlayerGameStartTime(gameInProgress: Bool){
    if gameInProgress {
        for var player in currentLineup[0]{ // Playing
            player.isPlaying = true
            player.timeCameOn = Int(Date().timeIntervalSince1970)
            print(player)
        }

        for var player in currentLineup[1]{ // Subs
            player.isPlaying = false
            player.timeCameOn = 0
        }
    }
}

我在日志中注意到以下内容：

Player(name: "Player 1", isPlaying: true, timeCameOn: 1488304289, currentPlayedTime: 0)
Player(name: "Player 2", isPlaying: true, timeCameOn: 1488304289, currentPlayedTime: 0)
Player(name: "Player 3", isPlaying: true, timeCameOn: 1488304289, currentPlayedTime: 0)
Player(name: "Player 4", isPlaying: true, timeCameOn: 1488304289, currentPlayedTime: 0)
Player(name: "Player 1", isPlaying: false, timeCameOn: 0, currentPlayedTime: 0)

更新我通过在viewdidload（）中调用一个名为currentLineup的函数来设置初始createInitialCurrentPlayingList()。

createInitialCurrentPlayingList(listOfPlayers: [Player]){
  for player in listOfPlayers {
    if startingLineup.count < 4 {
      startingLineup.append(player)
    } else {
       startingSubs.append(player) 
     } 
  }
   currentLineup.insert(startingLineup, at:0)
   currentLineup.insert(startingSubs, at: 1)
}

// declarations of vars
startingLineup: [Player] = []
startingSubs: [Player] = []
currentLineup: [[Player]] = []

Answer 1

这很可能是价值类型问题

请尝试此操作，它会将子阵列分配回currentLineup。

var firstLineup = currentLineup[0]
for player in firstLineup { // Playing
      player.isPlaying = true
      player.timeCameOn = Int(Date().timeIntervalSince1970)
      print(player)
}
currentLineup[0] = firstLineup

for in循环不更新元素

1 个答案: