为什么我的 SKAction 无法正常运行？

Question

好的，所以在我的 SpriteKit 游戏中，我有一个等待然后调用方法的 SKAction。我让这个动作永远重复。这些方法产生精灵。当我按下一个按钮（另一个精灵）时，游戏会暂停，并通过移除它来停止动作。当按下 resume 或 restart（还有 sprites）时，动作会再次开始，并且 sprites 会生成。

但是，当从后台返回（离开应用程序后）并自动调用暂停菜单方法时，当我按下恢复或重新启动按钮时，由于某种原因，该操作不会运行。这是我的代码：

在 GameScene.m 中：

-(void)createSceneContents {
self.isPaused = NO;
self.world = [SKNode node];


[self createUI];
[self createPauseMenu];

self.spawningSpeed = 1.5;
self.enemyData = [[Enemy alloc]init];
SKAction *wait = [SKAction waitForDuration:self.spawningSpeed];
SKAction *run = [SKAction performSelector:@selector(spawningEnemy) onTarget:self];
self.spawnAction = [SKAction repeatActionForever:[SKAction sequence:@[wait,run]]];
[self.world runAction:self.spawnAction withKey:@"spawn"];

[[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(wentToForeground) name:UIApplicationWillEnterForegroundNotification object:nil];

[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.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)createPauseMenu {
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);
}

-(void)spawningEnemy {

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];

}

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInNode:self];


if([self.pause containsPoint:location] && self.isPaused == NO){

    [self pauseGame];

}else if([self.resume containsPoint:location] && self.isPaused == YES) {
    [self resumeGame];
}else if ([self.restart containsPoint:location] && self.isPaused == YES){

    [self restartGame];

}else if (self.isTouchingGround == YES && self.isPaused == NO) {
    [self.playerData jump:self.player];
    NSLog(@"GOD YES");
    self.isTouchingGround = NO;
}
}

-(void)pauseGame {
[self createPauseMenu];
NSLog(@"Pausing...");
[self removeActionForKey:@"spawn"];
self.world.paused = YES;
[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.enemyData = nil;
self.isPaused = NO;
[self.pauseMusicPlayer stop];
[self createSceneContents];
[self runAction:self.spawnAction withKey:@"spawn"];
}

-(void)resumeGame {
self.isPaused = NO;
[self.pauseMusicPlayer stop];
[self runAction:self.spawnAction withKey:@"spawn"];
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];
}

-(void)wentToForeground {
[self pauseGame];
}

在 Enemy.m 中：

-(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;
}

Answer 1

即使您可能已经找到了答案，但我发现您的代码存在一些问题：

注意：self.spawnAction 必须是 Strong 属性，因此在删除时保持引用。

您正在self.world 上运行该操作，但在self 上将其删除。

[self.world runAction:self.spawnAction withKey:@"spawn"];

[self removeActionForKey:@"spawn"];
self.world.paused = YES;

如果您将 self.world 的 paused 属性设置为 YES，则无需删除操作，因为 pause 会立即暂停所有操作。

您没有在-(void)resumeGame 上再次将 paused 属性设置为 NO

然后你在 self 而不是 self.world 在简历上运行它。

总的来说，我会尽量避免使用暂停的属性，因为它们的行为可能不同并且不会给出你想要的结果。

另外，请记住，移除节点和操作不会立即发生，因此如果您之后暂停节点，您可能无法获得预期的结果。

此外，在 didEnterBackground 真正进入后台之前，您可以在有限的时间内完成您的工作。

希望对你有帮助。