how to release cocos2d objects?

I am doing as follows

-(void)Play {

[CCDirector setDirectorType:kCCDirectorTypeDisplayLink];

CCDirector *director = [CCDirector sharedDirector];
//[director setDeviceOrientation:kCCDeviceOrientationLandscapeLeft];

[director setAnimationInterval:1.0/60];

[director setDisplayFPS:NO];
CGRect rect = CGRectMake(0, 0, 320, 480);
EAGLView *glView = [EAGLView viewWithFrame:rect
                                   pixelFormat:kEAGLColorFormatRGB565   // kEAGLColorFormatRGBA8
                               depthFormat:0                        // GL_DEPTH_COMPONENT16_OES
                    ];

[director setOpenGLView:glView];

[window addSubview:glView];

[window makeKeyAn开发者_如何学PythondVisible]; 

[director setDisplayFPS:YES];

[CCTexture2D setDefaultAlphaPixelFormat:kCCTexture2DPixelFormat_RGBA8888];  

CCScene *scene = [CCScene node];
CCLayer *layer = [PongLayer node];
[scene addChild :layer];

[[CCDirector sharedDirector] runWithScene: scene];

 }

After adding layer to scene, I can go and see screen of PongLayer, but now how to destroy its object when you come back on the main screen from where you start game

I did change layers, but previous layer is working on back end, like if I do put some NSLog that I can see that log yet in running conditions, so what to do?

because when I again call play method, then I don't want to refresh all my array and all data for new scene.

Cocos2d objects such as CCLayer and CCSprite are coded to be auto release objects.

You'll see that the 'node' method alloc's inits and autoreleases an object when it's created.

Methods such as 'spriteWithFile:' and 'layerWithColor:' also are coded with autoreleased.

When you add an object as a child to a Layer or any other node for that matter, it creates a pointer to the object, retaining it. When the object is removed as a child, it deallocates itself.

So, when you move from Scene to Scene, the scene that is removed, deallocates it's children (layers) and they in turn their children (sprites).

http://www.cocos2d-iphone.org/wiki/doku.php/start

The only exception is when you create a sprite like this..

CCSprite *mySprite = [CCSprite alloc] init];

You have personally allocated and initialized this sprite, you must release it.

If you have CCLog turned on, it logs out when CCSprites are deallocated.

Another small thing worth mentioning, Scene's won't deallocate themselves if you 'push' the scene, only popping and replacing scene's cause 1 to deallocate.