为什么我的游戏在从后台回来后不能正常工作？

Question

我正在做一个即将完成的游戏，但我遇到了一个问题，我无法解决自己(老实说，存在多重问题，但让我们把这个问题留给其他问题吧)。

我的游戏是这样组织的: MainMenu -> GameScene --> nodes / GameOver暂停和GameOver菜单基本上是由雪碧和标签节点组成的。

在游戏中，有一个玩家需要避免接触敌人，每x个时间就产生一次。我通过重复一个永远运行代码块的SKAction来实现这一点。

当游戏暂停(当暂停按钮被击中)时，它会将布尔值(isPaused)更改为是，这会导致所有方法停止。它也移除敌人的产卵行动。

当游戏重新启动时，它会删除当前存在的所有内容，并重新创建整个场景。

这里的问题是:每当我单击“暂停”按钮时，就会显示出菜单，然后退出应用程序(只是背景，而不是实际退出)，然后返回并按重新启动，敌人不会产生ergo，操作也不会运行(节点计数也不会上升)。

，以下是一些代码：

我不会把所有的东西都放进去，所以如果你找到了一些引用不存在的东西，那么这个东西很可能就在原始代码中。

在GameScene.m中：

-(void)didMoveToView:(SKView *)view {
if (!self.contentCreated) {
    [self createSceneContents];
    self.contentCreated = YES;
    }
   }

-(void)createSceneContents {
self.isTouchingGround = NO;
self.isPaused = NO;
self.world = [SKNode node];
NSLog(@"likewhatever");
self.playerCategory = 1;
self.enemyCategory = 2;
self.edgeCategory = 4;
self.bottomCategory = 8;
self.playerScore = 0;

[GameDataHelper sharedGameData].score = 0;

self.physicsWorld.contactDelegate = self;

SKSpriteNode *bottom = [SKSpriteNode spriteNodeWithColor:[SKColor blackColor] size:CGSizeMake(self.frame.size.width, 10)];
bottom.position = CGPointMake(self.frame.size.width/2, 0);
bottom.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:bottom.size];
bottom.physicsBody.dynamic = NO;
bottom.physicsBody.restitution = 0;
bottom.physicsBody.categoryBitMask = self.bottomCategory;
bottom.physicsBody.contactTestBitMask = self.playerCategory | self.enemyCategory;

SKSpriteNode *left = [[SKSpriteNode alloc]init];
left.size = CGSizeMake(1, self.frame.size.height);
left.position = CGPointMake(0, self.frame.size.height/2);
left.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:left.size];
left.physicsBody.dynamic = NO;
left.physicsBody.restitution = 0;

SKSpriteNode *right  = [[SKSpriteNode alloc]init];
right.size = CGSizeMake(1, self.frame.size.height);
right.position = CGPointMake(self.frame.size.width - 1, self.frame.size.height/2);
right.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:right.size];
right.physicsBody.dynamic = NO;
right.physicsBody.restitution = 0;


self.backgroundColor = [SKColor blackColor];
self.playerData = [[Player alloc]init];
self.customUnit = self.frame.size.width/7;
self.player = [self.playerData newPlayer:self.customUnit];
self.player.physicsBody.categoryBitMask = self.playerCategory;
self.player.physicsBody.contactTestBitMask = self.enemyCategory | self.edgeCategory | self.bottomCategory;
self.player.position = CGPointMake(CGRectGetMidX(self.frame), self.customUnit*5);
[self.playerData movementSetup];

[self createUI];

NSString *path = [NSString stringWithFormat:@"%@/gamemusic2.mp3", [[NSBundle mainBundle]resourcePath]];
NSURL *mainMusicURL = [NSURL fileURLWithPath:path];
self.mainMusicPlayer = [[AVAudioPlayer alloc]initWithContentsOfURL:mainMusicURL error:nil];
self.mainMusicPlayer.volume = 0.1;
self.mainMusicPlayer.numberOfLoops = -1;
[self.mainMusicPlayer play];

[self spawnObject];
[self addChild:self.world];
[self.world addChild:bottom];
[self.world addChild:self.player];
[self addChild:left];
[self addChild:right];
[self addChild:self.pause];
[self addChild:self.scoreLabelInGame];
[self addChild:self.actualScore];



}

-(void)createUI {

self.pause = [SKSpriteNode spriteNodeWithImageNamed:@"pausebutton.png"];
self.pause.size = CGSizeMake(self.customUnit,self.customUnit);
self.pause.name = @"pauseButton";
self.pause.position = CGPointMake(30, self.frame.size.height - 30);

self.pausedImage = [SKSpriteNode spriteNodeWithImageNamed:@"paused.png"];
self.pausedImage.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame)*1.5);

self.restart = [SKLabelNode labelNodeWithFontNamed:@"Futura"];
self.restart.text = @"RESTART";
self.restart.fontSize = 25;
self.restart.position = CGPointMake(CGRectGetMidX(self.frame), self.pausedImage.position.y - self.pausedImage.position.y/5);

self.resume = [SKLabelNode labelNodeWithFontNamed:@"Futura"];
self.resume.text = @"RESUME";
self.resume.fontSize = 25;
self.resume.position = CGPointMake(self.restart.position.x, self.restart.position.y - self.customUnit);

self.scoreLabelInGame = [SKLabelNode labelNodeWithFontNamed:@"Futura"];
self.scoreLabelInGame.text = @"";
self.scoreLabelInGame.fontSize = 25;
self.scoreLabelInGame.position = CGPointMake(self.frame.size.width - 100, self.frame.size.height - 40);

self.actualScore = [SKLabelNode labelNodeWithFontNamed:@"Futura"];
self.actualScore.text = @"SCORE: 0";
self.actualScore.fontSize = 25;
self.actualScore.horizontalAlignmentMode = SKLabelHorizontalAlignmentModeRight;
self.actualScore.position = CGPointMake(self.frame.size.width - 20, self.frame.size.height - 40);


self.deathImage = [SKSpriteNode spriteNodeWithImageNamed:@"youdied.png"];
self.deathImage.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame)*1.5);
}

-(void)spawnObject {
NSLog(@"called");
if (self.isPaused == NO){
    NSLog(@"notpaused");
    self.spawningSpeed = 1.5;
    self.enemyData = [[Enemy alloc]init];
    SKAction *wait = [SKAction waitForDuration:self.spawningSpeed];
    SKAction *run = [SKAction runBlock:^{
        NSLog(@"spawned");
        SKSpriteNode *aNewEnemy = [self.enemyData createEnemyWithSize:self.customUnit andWidth:self.frame.size.width andHeight:self.frame.size.height + self.player.position.y];
        aNewEnemy.physicsBody.allowsRotation = NO;
        aNewEnemy.physicsBody.categoryBitMask = self.enemyCategory;
        aNewEnemy.physicsBody.collisionBitMask = self.enemyCategory | self.playerCategory | self.edgeCategory | self.bottomCategory;
        aNewEnemy.physicsBody.contactTestBitMask = self.enemyCategory | self.playerCategory | self.edgeCategory | self.bottomCategory;
        [self.world addChild:aNewEnemy];



    }];
    SKAction *action = [SKAction repeatActionForever:[SKAction sequence:@[wait,run]]];
    [self runAction:action withKey:@"spawn"];




}
}

-(void)didBeginContact:(SKPhysicsContact *)contact {

if (self.isPaused == NO) {

    SKPhysicsBody *firstBody, *secondBody;

    if (contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask) {
        firstBody = contact.bodyA;
        secondBody = contact.bodyB;
    }else {
        firstBody = contact.bodyB;
        secondBody = contact.bodyA;
    }
    if (firstBody.categoryBitMask == self.playerCategory && secondBody.categoryBitMask == self.bottomCategory) {
        self.isTouchingGround = YES;
    }
    if (firstBody.categoryBitMask == self.playerCategory && secondBody.categoryBitMask == self.enemyCategory) {
        self.isTouchingGround = YES;
        if ([secondBody.node.name isEqualToString:@"fallingEnemy"] && self.player.position.y < secondBody.node.position.y) {
           [self gameOver];
        }
    }

    if (firstBody.categoryBitMask == self.enemyCategory && secondBody.categoryBitMask == self.enemyCategory) {

        [self.enemyData changeBlock:firstBody.node];
        [self.enemyData changeBlock:secondBody.node];
        [self impactSound];

        [self updateScore];

        NSLog(@"Change1");
    }
    if (firstBody.categoryBitMask == self.enemyCategory && secondBody.categoryBitMask == self.bottomCategory) {
        NSLog(@"Change2");
        [self.enemyData changeBlock:firstBody.node];
        [self impactSound];

        [self updateScore];

    }





}
}

-(void)pauseGame {
NSLog(@"Pausing...");
[self removeActionForKey:@"spawn"];
[self addChild:self.pausedImage];
[self addChild:self.restart];
[self addChild:self.resume];

NSString *path = [NSString stringWithFormat:@"%@/menu_music.mp3", [[NSBundle mainBundle]resourcePath]];
NSURL *pauseMusicURL = [NSURL fileURLWithPath:path];
self.pauseMusicPlayer = [[AVAudioPlayer alloc]initWithContentsOfURL:pauseMusicURL error:nil];
self.pauseMusicPlayer.numberOfLoops = -1;
[self.pauseMusicPlayer play];

[self.pause removeFromParent];
self.scoreLabelInGame.position = CGPointMake(self.restart.position.x, self.resume.position.y - self.customUnit);
self.actualScore.position = CGPointMake(self.restart.position.x, self.scoreLabelInGame.position.y - self.customUnit);
self.isPaused = YES;
[self.mainMusicPlayer pause];
}

-(void)restartGame {
[self removeAllChildren];
[self removeAllActions];
self.isPaused = NO;
[self.pauseMusicPlayer stop];
[self createSceneContents];
}

-(void)resumeGame {
self.isPaused = NO;
[self.pauseMusicPlayer stop];
[self spawnObject];
self.scoreLabelInGame.position = CGPointMake(self.frame.size.width - 100, self.frame.size.height - 40);
self.actualScore.position = CGPointMake(self.frame.size.width - 20, self.frame.size.height - 40);
[self.mainMusicPlayer play];
[self.restart removeFromParent];
[self.resume removeFromParent];
[self.pausedImage removeFromParent];
[self addChild:self.pause];

}

-(void)gameOver {
NSLog(@"Game Over");
GameDataHelper *gameData = [[GameDataHelper alloc]init];

[self removeActionForKey:@"spawn"];
[self addChild:self.restart];
[self addChild:self.deathImage];
SKAction *gameOverSound = [SKAction playSoundFileNamed:@"gameover_tune.mp3" waitForCompletion:NO];
[self runAction:gameOverSound];

NSString *path = [NSString stringWithFormat:@"%@/menu_music.mp3", [[NSBundle mainBundle]resourcePath]];
NSURL *pauseMusicURL = [NSURL fileURLWithPath:path];
self.pauseMusicPlayer = [[AVAudioPlayer alloc]initWithContentsOfURL:pauseMusicURL error:nil];
self.pauseMusicPlayer.numberOfLoops = -1;
[self.pauseMusicPlayer play];
[self.pause removeFromParent];

SKLabelNode *highScore = [SKLabelNode labelNodeWithFontNamed:@"Futura"];
NSString *highScoreText = [NSString stringWithFormat:@"HIGHSCORE: %ld",[GameDataHelper sharedGameData].highScore];
highScore.text = highScoreText;
highScore.fontSize = 25;
highScore.position = CGPointMake(self.frame.size.width/2, self.restart.position.y - (2*self.customUnit));
[self addChild:highScore];

self.scoreLabelInGame.position = CGPointMake(self.restart.position.x, self.resume.position.y - self.customUnit);
self.actualScore.position = CGPointMake(self.restart.position.x, self.scoreLabelInGame.position.y - self.customUnit);
self.isPaused = YES;
[self.mainMusicPlayer pause];
   [gameData save];
}

在敌人：

-(SKSpriteNode *)createEnemyWithSize:(float)size andWidth:(float)width andHeight:(float)height {
self.enemy = [SKSpriteNode spriteNodeWithImageNamed:@"block.png"];
self.enemy.size = CGSizeMake(size - 5, size - 5);
self.enemy.name = @"fallingEnemy";
self.enemy.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:CGSizeMake(size - 3, size - 3)];
self.enemy.physicsBody.restitution = 0;
self.enemy.physicsBody.allowsRotation = NO;
int randomSection = arc4random_uniform(7);
switch (randomSection) {
    case 0:

        self.enemy.position = CGPointMake(2.5 + self.enemy.size.width/2, height-5);

        break;
    case 1:


        self.enemy.position = CGPointMake(width/7 + self.enemy.size.width/2, height-5);

        break;
    case 2:

        self.enemy.position = CGPointMake((width/7*2)  + self.enemy.size.width/2, height-5);

        break;
    case 3:

        self.enemy.position = CGPointMake((width/7*3)  + self.enemy.size.width/2, height-5);

        break;
    case 4:

        self.enemy.position = CGPointMake((width/7*4)  + self.enemy.size.width/2, height-5);

        break;
    case 5:

        self.enemy.position = CGPointMake((width/7*5)  + self.enemy.size.width/2, height-5);

        break;
    case 6:

        self.enemy.position = CGPointMake((width/7*6)  + self.enemy.size.width/2, height-5);


        break;
    default:

        break;
}


return self.enemy;
}

-(void)changeBlock:(SKNode *)block{
    block.physicsBody.dynamic = NO;
    block.name = @"staticEnemy";



}

Answer 1

我和你有一个非常相似的问题(并且注意到你的其他问题都是类似的)。幸运的是，我能够解决这个问题，并希望我能为你提供一些见解。

我的情况：，我正在创建一个基于物理的游戏，它使用粒子发射器和SKActions来处理游戏的某些方面。然而，我注意到这些“破坏”是在从insactive返回时发生的；也就是说，尽管所有属性在进入背景之前和之后都是相同的，但是粒子发射器没有显示任何东西，而且即使在从不活动状态返回后初始化它们，SKActions也不能工作。和你一样，我使用了一个自定义的"isPaused“变量来维护游戏状态。

My解决方案：将"isPaused“标志的名称更改为"gameIsPaused”。

，为什么？，我的研究让我相信，这与场景如何保持在孩子身上，以及SpriteKit进入后台时所做的事情有关。虽然苹果并没有公布幕后发生的事情，但各种论坛似乎都表明，当应用程序变得不活跃时，SpriteKit会自动暂停这一场景。

但是，通过拥有自己的"isPaused“变量，我认为您正在踩到一些导致bug的底层过程。

其他利用NSNotification中心(What is causing my SKAction timer to behave strangely?)的解决方案会像预期的那样重新命名"isPaused“标志。