ios - 如何在 objective-c 的AppDelegate中加载NSUserDefaults standardUserDefaults

Question

我不明白如何正确使用 NSUserDefaults standardUserDefaults。我有 GameOver.m 文件，检查分数是否为高分，如果是，它会像这样保存:

if(score > highScore){
  highScore =score;
  bestScore = highScore;

  NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
  [prefs setInteger:bestScore forKey:@"bestScore"];
  [prefs synchronize];
}

加载高分我使用:

NSUserDefaults *prefs =[NSUserDefaults standardUserDefaults];
NSInteger theHighScore =[prefs integerForKey:@"bestScore"];

它有效，但是在应用程序关闭并重新打开后，高分消失了，我读到，加载过程需要在 的 AppDelegate 文件中 - (void)applicationDidEnterBackground:(UIApplication *)application，如何我可以这样做吗？

编辑
GameScene.m

-(void)Scoring {
  NSUserDefaults *scoreprefs = [NSUserDefaults standardUserDefaults];
  [scoreprefs setInteger:score forKey:@"score"];
}

GameScene.m

#import "GameScene.h"
@implementation GameOver
NSInteger score;
NSInteger highScore;
NSInteger bestScore;

- (id)initWithSize:(CGSize)size playerLose:(BOOL)isLose {
  self = [super initWithSize:size];
  if (self) {
    NSUserDefaults *scoreprefs =[NSUserDefaults standardUserDefaults];
    NSInteger score = [scoreprefs integerForKey:@"score"];

    SKLabelNode *scorelabel = [SKLabelNode labelNodeWithFontNamed:@"Menlo-Bold"];
    scorelabel.text =[NSString stringWithFormat:@"%ld",(long)score];
    // then i define position/fontsize for scoreLabel
    [self addChild:scorelabel];

    if(score > highScore){
      highScore =score;
      bestScore = highScore;

      NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
      [prefs setInteger:bestScore forKey:@"bestScore"];
      [prefs synchronize];
    }

    NSUserDefaults *prefs =[NSUserDefaults standardUserDefaults];
    NSInteger theHighScore =[prefs integerForKey:@"bestScore"];
    SKLabelNode *highscorelabel = [SKLabelNode labelNodeWithFontNamed:@"Menlo-Bold"];
    highscorelabel.text =[NSString stringWithFormat:@"%ld",(long)theHighScore];
    //define position/fontsize for highscorelabel
  }
  return self;
}

就是这样，它。

Answer 1

@interface GameOver ()
@property (nonatomic, assign) NSInteger score;
@property (nonatomic, assign) NSInteger highScore;
@property (nonatomic, assign) NSInteger bestScore;
@end

@implementation GameOver
@synthesize score,bestScore,highScore;

- (id)initWithSize:(CGSize)size playerLose:(BOOL)isLose {
    NSUserDefaults *scoreprefs =[NSUserDefaults standardUserDefaults];

    if (self = [super initWithSize:size]) {
        if (self) {

            score = [scoreprefs integerForKey:@"score"];
            highScore = [scoreprefs integerForKey:@"bestScore"];

            SKLabelNode *scorelabel = [SKLabelNode labelNodeWithFontNamed:@"Menlo-Bold"];
            scorelabel.text =[NSString stringWithFormat:@"%ld",(long)score];
            // then i define position/fontsize for scoreLabel
            [self addChild:scorelabel];

            if(score > highScore){
                highScore =score;
                bestScore = highScore;

                [scoreprefs setInteger:bestScore forKey:@"bestScore"];
                [scoreprefs synchronize];
            }

            SKLabelNode *highscorelabel = [SKLabelNode labelNodeWithFontNamed:@"Menlo-Bold"];
            highscorelabel.text =[NSString stringWithFormat:@"%ld",(long)highScore];
            //define position/fontsize for highscorelabel
        }

    }
        return self;
}

问题是你没有初始化你的 HighScore ，并检查

score(assume 5242)>highScore(nil)

总是正确的

已编辑