cocos2d： 使用半单例

// Semi-Singleton: you can access MultiLayerScene only as long as it is the active scene.

static MultiLayerScene* multiLayerSceneInstance;



+(MultiLayerScene*) sharedLayer

{

    NSAssert(multiLayerSceneInstance != nil, @"MultiLayerScene not available!");

    return multiLayerSceneInstance;

}



-(void) dealloc

{

    multiLayerSceneInstance = nil;



    // don't forget to call "super dealloc"

    [super dealloc];

}

与普通的单例不同的是，它不能被初始化

 

使用单例的方法

 

MultiSceneLayer *sceneLayer=[MultiSceneLayer shareLayer];