关于xcode：如何使用SwiftUI显示Game Center排行榜

How to display Game Center leaderboard with SwiftUI

我创建了一个测试器应用，以测试将GameCenter排行榜添加到我正在创建的简单SwiftUI游戏中。我一直无法弄清楚如何显示所有分数的Game Center排行榜。

我创建了一个类，其中包含所有Game Center功能(身份验证和向排行榜添加得分。这是从主ContentView视图调用的。我不知道如何使它显示排行榜(甚至是游戏中心)登录屏幕(如果播放器尚未登录。)

这是我的GameCenterManager类：

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class GameCenterManager {
var gcEnabled = Bool() // Check if the user has Game Center enabled
var gcDefaultLeaderBoard = String() // Check the default leaderboardID
var score = 0
let LEADERBOARD_ID ="grp.colorMatcherLeaderBoard_1" //Leaderboard ID from Itunes Connect

// MARK: - AUTHENTICATE LOCAL PLAYER
func authenticateLocalPlayer() {
let localPlayer: GKLocalPlayer = GKLocalPlayer.local

localPlayer.authenticateHandler = {(ViewController, error) -> Void in
if((ViewController) != nil) {
print("User is not logged into game center")
} else if (localPlayer.isAuthenticated) {
// 2. Player is already authenticated & logged in, load game center
self.gcEnabled = true

// Get the default leaderboard ID
localPlayer.loadDefaultLeaderboardIdentifier(completionHandler: { (leaderboardIdentifer, error) in
if error != nil { print(error ??"error1")
} else { self.gcDefaultLeaderBoard = leaderboardIdentifer! }
})
print("Adding GameCenter user was a success")
} else {
// 3. Game center is not enabled on the users device
self.gcEnabled = false
print("Local player could not be authenticated!")
print(error ??"error2")
}
}
} //authenticateLocalPlayer()

func submitScoreToGC(_ score: Int){
let bestScoreInt = GKScore(leaderboardIdentifier: LEADERBOARD_ID)
bestScoreInt.value = Int64(score)
GKScore.report([bestScoreInt]) { (error) in
if error != nil {
print(error!.localizedDescription)
} else {
print("Best Score submitted to your Leaderboard!")
}
}
}//submitScoreToGc()
}

这是ContentView结构：

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struct ContentView: View {

//GameCenter
init() {
self.gameCenter = GameCenterManager()
self.gameCenter.authenticateLocalPlayer()
}

@State var score = 0
var gcEnabled = Bool() //Checks if the user had enabled GameCenter
var gcDefaultLeaderboard = String() //Checks the default leaderboard ID
let gameCenter: GameCenterManager

/*End GameCenter Variables */

var body: some View {

HStack {
Text("Hello, world!")
Button(action: {
self.score += 1
print("Score increased by 10. It is now \\(self.score)")
self.gameCenter.submitScoreToGC(self.score)

}) {
Text("Increase Score")

}
}
}
}

将非常感谢您为解决此问题提供的任何帮助。

相关讨论

我有个解决方法。

我在我的SwiftUI App声音匹配器中成功使用了Game Center。要遵循的代码段。

该代码不完全遵循SwiftUI声明性原理，但是可以完美地工作。我将片段添加到SceneDelegate和ContentView中，并使用GameKitHelper类，类似于Thomas为他的测试应用程序创建的类。我的版本基于在raywenderlich.com上找到的代码。

我实际上是按照与bg2b相同的思路尝试使用符合UIViewControllerRepresentable的结构作为我的第一次尝试，但是它一直抱怨游戏中心视图控制器需要以模态显示。最终，我放弃了尝试，尝试了我目前更成功的方法。

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class SceneDelegate: UIResponder, UIWindowSceneDelegate {

let contentView = ContentView()
.environmentObject(GameKitHelper.sharedInstance) // publish enabled state

func scene(_ scene: UIScene, willConnectTo session: UISceneSession,
options connectionOptions: UIScene.ConnectionOptions) {

if let windowScene = scene as? UIWindowScene {
let window = UIWindow(windowScene: windowScene)

window.rootViewController = UIHostingController(rootView: contentView)
// new code to create listeners for the messages
// you will be sending later
PopupControllerMessage.PresentAuthentication
.addHandlerForNotification(
self,
handler: #selector(SceneDelegate
.showAuthenticationViewController))

PopupControllerMessage.GameCenter
.addHandlerForNotification(
self,
handler: #selector(SceneDelegate
.showGameCenterViewController))

// now we are back to the standard template
// generated when your project was created
self.window = window
window.makeKeyAndVisible()
}
}
// pop's up the leaderboard and achievement screen
@objc func showGameCenterViewController() {
if let gameCenterViewController =
GameKitHelper.sharedInstance.gameCenterViewController {
self.window?.rootViewController?.present(
gameCenterViewController,
animated: true,
completion: nil)
}

}
// pop's up the authentication screen
@objc func showAuthenticationViewController() {
if let authenticationViewController =
GameKitHelper.sharedInstance.authenticationViewController {

self.window?.rootViewController?.present(
authenticationViewController, animated: true)
{ GameKitHelper.sharedInstance.enabled =
GameKitHelper.sharedInstance.gameCenterEnabled }
}
}
}

// content you want your app to display goes here
struct ContentView: View {

@EnvironmentObject var gameCenter : GameKitHelper
@State private var isShowingGameCenter = false { didSet {
PopupControllerMessage
.GameCenter
.postNotification() }}

var body: some View {
VStack {
if self.gameCenter.enabled
{
Button(action:{ self.isShowingGameCenter.toggle()})
{ Text(
"Press to show leaderboards and achievements")}
}
// The authentication popup will appear when you first enter
// the view
}.onAppear() {GameKitHelper.sharedInstance
.authenticateLocalPlayer()}
}
}

import GameKit
import UIKit

// Messages sent using the Notification Center to trigger
// Game Center's Popup screen
public enum PopupControllerMessage : String
{
case PresentAuthentication ="PresentAuthenticationViewController"
case GameCenter ="GameCenterViewController"
}

extension PopupControllerMessage
{
public func postNotification() {
NotificationCenter.default.post(
name: Notification.Name(rawValue: self.rawValue),
object: self)
}

public func addHandlerForNotification(_ observer: Any,
handler: Selector) {
NotificationCenter.default .
addObserver(observer, selector: handler, name:
NSNotification.Name(rawValue: self.rawValue), object: nil)
}

}

// based on code from raywenderlich.com
// helper class to make interacting with the Game Center easier

open class GameKitHelper: NSObject, ObservableObject, GKGameCenterControllerDelegate {
public var authenticationViewController: UIViewController?
public var lastError: Error?

private static let _singleton = GameKitHelper()
public class var sharedInstance: GameKitHelper {
return GameKitHelper._singleton
}

private override init() {
super.init()
}
@Published public var enabled :Bool = false

public var gameCenterEnabled : Bool {
return GKLocalPlayer.local.isAuthenticated }

public func authenticateLocalPlayer () {
let localPlayer = GKLocalPlayer.local
localPlayer.authenticateHandler = {(viewController, error) in

self.lastError = error as NSError?
self.enabled = GKLocalPlayer.local.isAuthenticated
if viewController != nil {
self.authenticationViewController = viewController
PopupControllerMessage
.PresentAuthentication
.postNotification()
}
}
}

public var gameCenterViewController : GKGameCenterViewController? { get {

guard gameCenterEnabled else {
print("Local player is not authenticated")
return nil }

let gameCenterViewController = GKGameCenterViewController()

gameCenterViewController.gameCenterDelegate = self

gameCenterViewController.viewState = .achievements

return gameCenterViewController
}}

open func gameCenterViewControllerDidFinish(_
gameCenterViewController: GKGameCenterViewController) {

gameCenterViewController.dismiss(
animated: true, completion: nil)
}

}