所以繁榮我又回來了另一個可能愚蠢的問題，哈哈。我正在擴展我在 YouTube 教程中找到的直升機游戲作為學習練習。我卡上是我想要使用的核心資料，讓用戶保存自己的分數，當他們死了，記得在一個單獨的視圖保存那些成績從本場比賽的主螢屏訪問的部分（我用ContentView的主螢屏和GameView實際游戲的單獨螢屏）。在我的資料模型中，我定義了一個物體“Scores”，具有一個屬性“name”。檔案中的核心資料使用GameView沒有回傳錯誤，但是當我嘗試在要列出分數的視圖中獲取資料時，出現錯誤：
'FetchedResults' 型別的值沒有成員 'name'
這里是代碼GameView：
//
// GameView.swift
// Helicopter
//
// Created by Instinct on 10/18/21.
//
import SwiftUI
import AVKit
import CoreData
struct GameView: View{
@State var audioPlayer: AVAudioPlayer!
@State private var heliPosition = CGPoint(x:100, y:100)
@State private var obstPosition = CGPoint(x:1000, y:300)
@State private var flatObstPosition = CGPoint(x:1000, y: 100)
@State var timer = Timer.publish(every: 0.2, on: .main, in: .common).autoconnect()
@State var isPaused = false
@State private var score = 0
@Environment(\.managedObjectContext) var context
// @FetchRequest(entity: Scores.entity(), sortDescriptors: []) var scores: FetchedResults<Scores>
@State public var newScoreValue = ""
@State public var selectedScore: Scores?
let groundPosition = CGPoint(x: 0, y: 1000)
func gravity(){
withAnimation{
self.heliPosition.y = 50
}
}
func obstMove(){
if self.obstPosition.x > 0
{
withAnimation{
self.obstPosition.x -= 20
}
}
else
{
self.obstPosition.x = 1000
self.obstPosition.y = CGFloat.random(in: 0...500)
}
}
func flatObstMove(){
if self.flatObstPosition.x > 0
{
withAnimation{
self.flatObstPosition.x -= 20
}
}
else
{
self.flatObstPosition.x = 1000
self.flatObstPosition.y = CGFloat.random(in: 0...500)
}
}
func pause(){
self.timer.upstream.connect().cancel()
// self.isPaused = true
}
func restart(){
self.timer = Timer.publish(every: 0.2, on: .main, in: .common).autoconnect()
self.obstPosition.x = 1000
self.flatObstPosition.x = 1000
self.heliPosition = CGPoint(x:100, y:100)
self.isPaused = false
self.score = 0
}
func resume(){
self.timer = Timer.publish(every: 0.2, on: .main, in: .common).autoconnect()
self.obstPosition.x = 1000
self.flatObstPosition.x = 1000
self.heliPosition = CGPoint(x:100, y:100)
self.isPaused = false
}
func collisionDetection(){
if abs(heliPosition.x - obstPosition.x) < (25 20) && abs(heliPosition.y - obstPosition.y) < (25 100){
pause()
self.isPaused = true
// self.score = 0
}
if abs(heliPosition.x - flatObstPosition.x) < (25 150) && abs(heliPosition.y - flatObstPosition.y) < (25 30){
pause()
self.isPaused = true
// self.score = 0
}
}
// func startGame(){
// self.timer = Timer.publish(every: 0.2, on: .main, in: .common).autoconnect()
// self.obstPosition.x = 1000
// self.heliPosition = CGPoint(x:100, y:100)
// self.isPaused = false
// self.score = 0
// }
func fallOffDetection(){
if abs(heliPosition.y) > 800{
pause()
self.isPaused = true
}
}
func levelDetection(){
// if self.isPaused == true{
// self.timer.upstream.connect().cancel()
// }
if self.score >= abs(100){
self.timer = Timer.publish(every: 0.1, on: .main, in: .common).autoconnect()
}
else if self.score >= abs(300){
self.timer = Timer.publish(every: 0.05, on: .main, in: .common).autoconnect()
}
else{
// Text("Level 1")
self.timer = Timer.publish(every: 0.2, on: .main, in: .common).autoconnect()
}
}
func save(scores: Scores?) {
if self.selectedScore == nil {
let newScore = Scores(context: self.context)
newScore.name = newScoreValue
try? self.context.save()
}
// else {
// context.performAndWait {
// scores!.name = self.newScoreValue
// try? context.save()
// self.newScoreValue = ""
// self.selectedScore = nil
// }
// }
}
var body: some View {
GeometryReader{ geo in
ZStack{
Helicopter()
.position(self.heliPosition)
.onReceive(self.timer){_ in
self.gravity()
// self.levelDetection()
}
Obstacle()
.position(self.obstPosition)
.onReceive(timer){_ in
// withAnimation{
self.obstMove()
// }
}
FlatObstacle()
.position(self.flatObstPosition)
.onReceive(timer){_ in
self.flatObstMove()
}
Ground()
.position(self.groundPosition)
self.isPaused ? HStack {
Spacer()
Button("restart"){self.restart()}.font(.system(size: 40))
Spacer()
Button("resume"){self.resume()}.font(.system(size:40))
Spacer()
Button("save score"){self.save(scores: selectedScore)}
}: nil
self.isPaused ? Text("your final score is " String(self.score)) .position(x: geo.size.width / 2, y: geo.size.height - 700).foregroundColor(Color.white).font(.system(size: 50)): nil
TextField("\(self.score)", text: $newScoreValue)
.foregroundColor(.white)
.position(x: geo.size.width - 100, y: geo.size.height / 10)
.multilineTextAlignment(.trailing)
// Spacer()
Ground()
// .frame(width: 1000, height: 200)
.foregroundColor(Color.blue)
}
// .onAppear {
// let sound = Bundle.main.path(forResource: "Calboy - All Night Long_2", ofType: "mp3")
// self.audioPlayer = try! AVAudioPlayer( contentsOf: URL(fileURLWithPath: sound!))
//
// }
// }
.frame(width: geo.size.width, height: geo.size.height)
.background(Color.black)
.gesture(
DragGesture()
.onChanged{ value in
withAnimation{
// self.heliPosition.x = heliPosition.x
self.heliPosition.y = value.location.y
}
}
.onEnded{_ in
self.levelDetection()
})
// TapGesture()
// .onEnded{
// withAnimation{
// self.heliPosition.y -= 100
// }
// })
// .onReceive(self.timer){_ in
// self.levelDetection()
// }
}
.onReceive(self.timer) {_ in
self.collisionDetection()
self.score = 1
}
.onReceive(self.timer){_ in
self.fallOffDetection()
// self.score = 0
}
.edgesIgnoringSafeArea(.all)
}
}
struct GameView_Previews: PreviewProvider {
static var previews: some View {
GameView()
}
}
這是分數串列的代碼
//
// ViewScores.swift
// Helicopter
//
// Created by Instinct on 10/19/21.
//
import SwiftUI
import CoreData
struct ScoresList: View{
@Environment(\.managedObjectContext) var context
@FetchRequest(entity: Scores.entity(), sortDescriptors: []) var scores: FetchedResults<Scores>
// @State public var newScoreValue = ""
// @State public var selectedScore: Scores?
// @State private var newScoreValue = ""
// @State private var selectedScore: Scores?
// func load(scores: Scores?) {
// if self.selectedScore == nil {
// let newScore = Scores(context: self.context)
// newScore.name = newScoreValue
// try? self.context.()
// }
var body: some View{
List{
ForEach(scores, id: \.self) { score in
Text("\(scores.name!)")
// .onTapGesture {
// self.newScore = savedScores.name
// self.selectedScore = savedScores
// }
}
}
}
}
以防萬一，這里是我AppDelegate檔案中的代碼：
//
// AppDelegate.swift
// CoreDataCRUD
//
// Created by Krassimir Iankov on 8/7/20.
// Copyright ? 2020 Krassimir Iankov. All rights reserved.
//
import UIKit
import CoreData
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
// Override point for customization after application launch.
return true
}
// MARK: UISceneSession Lifecycle
func application(_ application: UIApplication, configurationForConnecting connectingSceneSession: UISceneSession, options: UIScene.ConnectionOptions) -> UISceneConfiguration {
// Called when a new scene session is being created.
// Use this method to select a configuration to create the new scene with.
return UISceneConfiguration(name: "Default Configuration", sessionRole: connectingSceneSession.role)
}
func application(_ application: UIApplication, didDiscardSceneSessions sceneSessions: Set<UISceneSession>) {
// Called when the user discards a scene session.
// If any sessions were discarded while the application was not running, this will be called shortly after application:didFinishLaunchingWithOptions.
// Use this method to release any resources that were specific to the discarded scenes, as they will not return.
}
// MARK: - Core Data stack
lazy var persistentContainer: NSPersistentContainer = {
/*
The persistent container for the application. This implementation
creates and returns a container, having loaded the store for the
application to it. This property is optional since there are legitimate
error conditions that could cause the creation of the store to fail.
*/
let container = NSPersistentContainer(name: "Scores")
container.loadPersistentStores(completionHandler: { (storeDescription, error) in
if let error = error as NSError? {
// Replace this implementation with code to handle the error appropriately.
// fatalError() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
/*
Typical reasons for an error here include:
* The parent directory does not exist, cannot be created, or disallows writing.
* The persistent store is not accessible, due to permissions or data protection when the device is locked.
* The device is out of space.
* The store could not be migrated to the current model version.
Check the error message to determine what the actual problem was.
*/
fatalError("Unresolved error \(error), \(error.userInfo)")
}
})
return container
}()
// MARK: - Core Data Saving support
func saveContext () {
let context = persistentContainer.viewContext
if context.hasChanges {
do {
try context.save()
} catch {
// Replace this implementation with code to handle the error appropriately.
// fatalError() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
let nserror = error as NSError
fatalError("Unresolved error \(nserror), \(nserror.userInfo)")
}
}
}
}
我再次搜索了互聯網和檔案，但無法弄清楚這一點。任何幫助是極大的贊賞！
uj5u.com熱心網友回復：
讓您的 Text 使用 ForEach 中的變數
Text("\(score.name!)")
注意單數，復數是陣列。
轉載請註明出處，本文鏈接：https://www.uj5u.com/shujuku/326240.html
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