Cocos2d CCScene & CCLayer setup - cocos2d-iphone

Sorry for the newbie question but I was wondering what the difference is between these two different setups for the scene & the layer? I have tried both ways and each one works but I just don't know what the difference is or which one I should use.
#implementation Game
+(id) scene {
CCScene *scene = [CCScene node];
[scene addChild:[Game node]];
return scene; }
Or this way.
#implementation Game
+(id) scene {
CCScene *scene = [CCScene node];
Game *layer = [Game node];
[scene addChild:layer];
return scene; }

I don't see any difference between your 2 sample of code. Your 2 methods are identically the same.
[Game node] returns a layer so in the first case you add it directly into your scene and in the 2 example you just put it into a variable then add it into your scene.
For the compiler this is the same thing here.

Related

Getting black screen when using CCLayerPanZoom instead of CCLayer

To be able to pan and zoom some of the content in screen I decided to use CCLayerPanZoom extension. When I look at the source code I can see that it derives from the CCLayer class. So I change the parent class of the node that's pushed to the navigation stack from CCLayer to CCLayerPanZoom. But what I get when the app launches is just a black screen. To make it cleaner, I created a new class, derived it from CCLayerPanZoom, added a test sprite onto it in the init method and pushed it to the navigation stack in the AppDelegate.m. Still I got nothing, just a black screen. Here're the two methods that I've implemented in my class:
#interface TestPanZoom : CCLayerPanZoom {
}
+(CCScene *) scene;
#end
#implementation TestPanZoom
+(CCScene *) scene
{
// 'scene' is an autorelease object.
CCScene *scene = [CCScene node];
// 'layer' is an autorelease object.
TestPanZoom *layer = [TestPanZoom node];
// add layer as a child to scene
[scene addChild: layer];
// return the scene
return scene;
}
-(id)init{
if(self=[super init])
{
CCSprite *sprite=[CCSprite spriteWithFile:#"Default.png"];
sprite.scale=0.5;
[self addChild:sprite];
}
return self;
}
#end

Cocos2d restart current scene

I've got an end of level layer added to game, each level has its own scene. I want to be able to restart the current scene. Obviously the scene will change but the layer will remain the same. How is this done. I've tried-
CCScene *currentScene = [[CCDirector sharedDirector]runningScene];
[[CCDirector sharedDirector]replaceScene:currentScene];
Thanks
This does not work because you can't replace the same scene object with itself:
CCScene *currentScene = [[CCDirector sharedDirector]runningScene];
[[CCDirector sharedDirector]replaceScene:currentScene];
Instead you have to create a new instance of your scene, like so:
[[CCDirector sharedDirector] replaceScene:[YourSceneClass scene]];
If you don't know what the current scene class is, then this ought to work:
CCScene *currentScene = [CCDirector sharedDirector].runningScene;
CCScene *newScene = [[[currentScene class] alloc] init];
[[CCDirector sharedDirector] replaceScene:newScene];
Assuming you're using ARC as everyone should these days. Otherwise add an autorelease.
I ran into the same problem. I tried this
CCScene *currentScene = [CCDirector sharedDirector].runningScene;
CCScene *newScene = [[[currentScene class] alloc] init];
[[CCDirector sharedDirector] replaceScene:newScene];
and it gave me a blank screen.
The problem is this line
CCScene *newScene = [[[currentScene class] alloc] init];
[currentScene class] actually returns CCScene..
Hence
[CCScene alloc] init] gives us a blank screen.
The way how I got around this problem was by setting tag for each of my scene class.
For example:
+(CCScene *) scene
{
// 'scene' is an autorelease object.
CCScene *scene = [CCScene node];
scene.tag = 1;
// 'layer' is an autorelease object.
GameOneLayer * layer = [[[GameOneLayer alloc] init];
// add layer as a child to scene
[scene addChild: layer];
// return the scene
return scene;
}
Hope this helps.

arc enabled cocos2d - old scene lives after replaceScene

I'm trying to implement a game with cocos2d. I enabled arc according to the instructions on this tutorial.
http://www.learn-cocos2d.com/2012/04/enabling-arc-cocos2d-project-howto-stepbystep-tutorialguide/
I realized a weird behavior after replacing game scene with main menu scene and I can't figure out the problem. After replacement, the new scene appears and works as I expected, but the game scene (old scene) still reacts touches. I thought that when I replace the scene, old scene should be removed completely, but it continue to live under the new scene.
Some of the relevant code is as follows:
Singleton:
+(void) go: (CCLayer *) layer{
CCDirector *director = [CCDirector sharedDirector];
CCScene *newScene = [Singelton wrap:layer];
if ([director runningScene]) {
[director replaceScene: [CCTransitionFlipX transitionWithDuration:0.5 scene:newScene]];
} else {
[director pushScene:newScene];
}
}
+(CCScene *) wrap: (CCLayer *) layer{
CCScene *newScene = [CCScene node];
[newScene addChild: layer];
return newScene;
}
+(void) mainMenu
{
CCLayer *layer = [MainMenu node];
[Singleton go:layer];
}
When I need to go to main menu scene I call singleton class as follows
[Singleton mainMenu]
How can I kill the game scene after menu scene appears?
Thanks for your help.
What does Singleton do? I suspect that it might be the cause, holding on to references of the Scene/Layer or any other nodes while/after replacing a scene.

ccscene arc and autorelease

I am trying to construct a number of scenes in my GameManager singleton init.
The scene is created via
- (id)init
{
self = [super init];
if (self) { // 'mainScene' is an autorelease object.
mainScene = [CCScene node];
...
}
GameManger holds a strong reference to mainScene:
#interface GameManager : NSObject
{
CCScene* mainScene;
}
But if I try to push the scene later with
[[CCDirector sharedDirector] pushScene:mainScene];
I get EXC_BAD_ACCESS
If I create and immediately push then everything works. Shouldn't the default __strong reference keep the object allocated?
Thanks in advance for any help....
Figured it out ... [CCScene node] is a convenience factory method that does:
[[[self alloc] init] autorelease];
but since I am using arc...I dont want that - I want
mainScene = [[CCScene alloc]init];
instead of
mainScene = [CCScene node];

Switching scenes with inputs

Here's the code I know to change scenes with cocos2d:
[[CCDirector sharedDirector] replaceScene:[HelloWorld scene]];
But I wonder if it's possible I can switch the scenes with some parameters.
I tried this method:
HelloWorld *scene = [HelloWorld scene];
[scene initWithInput:0];
[[CCDirector sharedDirector] replaceScene:scene];
-(void)initWithInput:(int)input is what I wrote for test in HelloWorld class.
And it does't work, does any one know how to do it?
Try overriding the scene method. Something like
+(id) sceneWithInput:(int) i
{
// 'scene' is an autorelease object.
CCScene *scene = [CCScene node];
// 'layer' is an autorelease object.
HelloWorld *layer = [HelloWorld nodeWithInput:i];
// add layer as a child to scene
[scene addChild: layer];
// return the scene
return scene;
}
Then you would call
[[CCDirector sharedDirector] replaceScene:[HelloWorld sceneWithInput:0]];