为什么我无法联系 Xcode 中的外部 .swift 文档

Why can't I contact an external .swift document in Xcode

我正在 Swift 制作一个简单的 SpriteKit 游戏。我制作了一个文件 "EmemyAppear.swift" 并在其中放了一个 class 和一个函数。这就是这个文件中的内容:

import Foundation
class EnemyAppear {
var nowAppear = false
var waitToAppear = UInt32(0)
var appearInterval = UInt32(0)
init(nowAppear:Bool, waitToAppear:UInt32, appearInterval:UInt32) {
    self.nowAppear = nowAppear
    self.waitToAppear = waitToAppear
    self.appearInterval = appearInterval
}

func shouldRun() -> Bool {
    return self.appearInterval > self.waitToAppear
}

}

于是我在主场景做了一个字典:

var enemyStatus:Dictionary<String,EnemyAppear> = [:]`

之后,我尝试从 EnemyAppear.swift 联系变量和函数,如下所示:

func enemyRun() {
    for(enemy, enemyAppear) in self.enemyStatus {
    var thisPet = self.childNodeWithName(enemy)!
        if enemyStatus.shouldRun() {
            enemyStatus.waitToAppear = random()
            enemyStatus.appearInterval = 0
            enemyStatus.nowAppear = true
        }
    }
}

但是 Xcode 告诉我 Dictionary <String, EnemyAppear> doesn't have a member named 'shouldRun' 但确实如此。我做错了什么?

if enemyStatus.shouldRun() 

enemyStatus 是字典,不是 EnemyAppear,因此它没有名为 'shouldRun' 的成员。应该是

if enemyAppear.shouldRun()