Question

我正在尝试使用2个按钮作为初始场景呈现菜单：play，credits。点击play后，我想展示另一个包含4个按钮的菜单场景：tutorial，easy，hard，back。
该策略只是将按钮创建为SKSpriteNode个对象并处理touchesBegan函数中的点击。

在我的menuScene.sks文件中，我正确放置并命名了我的节点。在这里，您可以查看链接到此场景的menuScene.swift文件：

import SpriteKit

class menuScene: SKScene {

var playButton:SKSpriteNode!
var creditsButton:SKSpriteNode!

override func didMove(to view: SKView) {
    playButton = self.childNode(withName: "playButton") as! SKSpriteNode
    creditsButton = self.childNode(withName: "creditsButton") as! SKSpriteNode
}

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    // transition is defined in Helper.swift
    let touch = touches.first

    if let location = touch?.location(in: self){

        let nodesArray = self.nodes(at: location)

        if nodesArray.first?.name == "playButton" {
            let nextScene = difScene(size: self.size)
            self.view?.presentScene(nextScene, transition: transition)
        } else if nodesArray.first?.name == "creditsButton" {
            let nextScene = creditsScene(size: self.size)
            self.view?.presentScene(nextScene, transition: transition)
        }
    }
  }
}

当我运行时，menuScene显示没有问题。但是当我触摸play按钮时，我收到一个错误，它来自下一个场景：difScene。在这里，您可以找到difScene.swift：

import SpriteKit

class difScene: SKScene {

var tutButton:SKSpriteNode!
var easyButton:SKSpriteNode!
var hardButton:SKSpriteNode!
var backButton:SKSpriteNode!

override func didMove(to view: SKView) {
    tutButton = self.childNode(withName: "tutButton") as! SKSpriteNode // error
    easyButton = self.childNode(withName: "easyButton") as! SKSpriteNode
    hardButton = self.childNode(withName: "hardButton") as! SKSpriteNode
    backButton = self.childNode(withName: "backButton") as! SKSpriteNode
}

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    let transition = SKTransition.push(with: .down, duration: 0.2)
    let touch = touches.first

    if let location = touch?.location(in: self){

        let nodesArray = self.nodes(at: location)
        if nodesArray.first?.name == "tutButton" {

            let nextScene = GameScene(size: self.size)
            self.view?.presentScene(nextScene, transition: transition)
        }

        if nodesArray.first?.name == "easyButton" {
            let nextScene = difScene(size: self.size)
            self.view?.presentScene(nextScene, transition: transition)
        }

        if nodesArray.first?.name == "hardButton" {
            let nextScene = difScene(size: self.size)
            self.view?.presentScene(nextScene, transition: transition)
        }

        if nodesArray.first?.name == "backButton" {
            let nextScene = menuScene(size: self.size)
            self.view?.presentScene(nextScene, transition: transition)
        }
    }
  }
}

如果它可能有用，这是我的GameViewController.swift：

import UIKit
import SpriteKit
import GameplayKit

class GameViewController: UIViewController {

override func viewDidLoad() {
    super.viewDidLoad()

    if let scene = GKScene(fileNamed: "menuScene") {

        // Get the SKScene from the loaded GKScene
        if let sceneNode = scene.rootNode as! menuScene? {

            // Set the scale mode to scale to fit the window
            sceneNode.scaleMode = .aspectFill

            // Present the scene
            if let view = self.view as! SKView? {
                view.presentScene(sceneNode)

                view.ignoresSiblingOrder = true

                view.showsFPS = false
                view.showsNodeCount = false
            }
        }
    }
}

override var shouldAutorotate: Bool {
    return true
}

override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
    if UIDevice.current.userInterfaceIdiom == .phone {
        return .allButUpsideDown
    } else {
        return .all
    }
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Release any cached data, images, etc that aren't in use.
}

override var prefersStatusBarHidden: Bool {
    return true
  }
}

我得到的错误是：

线程1：致命错误：在解包可选值时意外发现nil

我知道这不是一个独特的错误。我有谷歌，看过教程，并试图从其他StackOverflow线程派生出一个解决方案，但未能克服这个问题。

SpriteKit：在解包时意外找到nil，无法实现多个菜单场景

0 个答案: