CCDirector replaceScene issues « cocos2d for iPhone

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CCDirector replaceScene issues

(22 posts) (9 voices)

Started 2 years ago by JavaWizKid
Latest reply from dany

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JavaWizKid
Member

I've been using:
[[CCDirector sharedDirector] replaceScene:[CCFadeTransition transitionWithDuration:1.0 scene:[MenuScene node]]];
and it works perfectly fine. However when I have been inside the game scene and want to go back to the menu I implement this code to be activated from a UIAlertView:

- (void)alertView:(UIAlertView *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex {
// the user clicked one of the OK/Cancel buttons
if (buttonIndex == 0)
{
NSLog(@"Go To Menu");
enemyblob.position = ccp(240, 650);
blob.position = ccp(240, 350);
blob.score=0;
enemyblob.score=0;
isPlaying = 0;
[[CCDirector sharedDirector] replaceScene:[CCFadeTransition transitionWithDuration:1.0 scene:[MenuScene node]]];
}
}

This works fine, however about 2 seconds later, the app crashes and displays no errors in the console. Any ideas?

Posted 2 years ago #
riq
Key Master

what do you mean by "no errors". Can you see the crash report and/or traceback ?

Posted 2 years ago #
riq
Key Master

Please, don't forget to mention which cocos2d version are you using.

Posted 2 years ago #
JavaWizKid
Member

I ran it in debug mode and console spat out "Program received signal: “EXC_BAD_ACCESS”." It doesn't state specifically where it's coming from :S I'm using Cocos2d version 0.9.0

Here is the bit of the console output when the crash happens:

2010-01-11 18:43:15.548 Blob Arena[2605:207] Go To Menu
2010-01-11 18:43:16.573 Blob Arena[2605:207] cocos2d: deallocing <CCFadeIn = 03C24B00 | Tag = -1>
2010-01-11 18:43:16.574 Blob Arena[2605:207] cocos2d: deallocing <CCCallFunc = 03C0A640 | Tag = -1>
2010-01-11 18:43:16.576 Blob Arena[2605:207] cocos2d: deallocing <CCSequence = 03C5C870 | Tag = -1>
2010-01-11 18:43:16.577 Blob Arena[2605:207] cocos2d: deallocing <CCFadeOut = 03C922D0 | Tag = -1>
2010-01-11 18:43:16.577 Blob Arena[2605:207] cocos2d: deallocing <CCSequence = 03C0CE00 | Tag = -1>
2010-01-11 18:43:16.578 Blob Arena[2605:207] cocos2d: deallocing <CCCallFunc = 03C7B360 | Tag = -1>
2010-01-11 18:43:16.578 Blob Arena[2605:207] cocos2d: deallocing <CCSequence = 03C0AE90 | Tag = -1>
2010-01-11 18:43:16.605 Blob Arena[2605:207] cocos2d: deallocing <CCStandardTouchHandler: 0x3c3b620>
2010-01-11 18:43:16.608 Blob Arena[2605:207] cocos2d: deallocing <CCColorLayer = 03C87A70 | Tag = -86050082>
2010-01-11 18:43:16.624 Blob Arena[2605:207] cocos2d: deallocing <CCTimer = 03C6A170 | target:CCFadeTransition selector:(setNewScene:)>
2010-01-11 18:43:16.626 Blob Arena[2605:207] cocos2d: deallocing <CCTextureAtlas = 03AE0EE0 | totalQuads = 1>
2010-01-11 18:43:16.627 Blob Arena[2605:207] cocos2d: deallocing <CCSprite = 03A3DBE0 | Rect = (0.00,0.00,60.00,60.00) | tag = -1>
2010-01-11 18:43:16.627 Blob Arena[2605:207] cocos2d: deallocing <Blob = 03A3F290 | Rect = (0.00,0.00,0.00,0.00) | tag = -1>

Posted 2 years ago #
JavaWizKid
Member

Any suggestions?

Posted 2 years ago #
Questor
Member

Greetings,

You should try creating a small complete sample of the code that produces the issue and post it. With EXC_BAD_ACCESS errors, the problem is often somewhere else than where you might think.

In general EXC_BAD_ACCESS it would indicate that you are referencing a released object, or referencing an object that has not been initialized. (In Java terms, think of it as similar to a NullPointerException)

Regards,
Q

Posted 2 years ago #
JavaWizKid
Member

Thanks I think I know what the problem is now but I don't know how to overcome it. Basically I'm trying to open a scene which is higher up (in a structure) from a low one. Eg: menu scene -> another scene -> game scene. I'm trying to go from game scene to menu scene. :s

Posted 2 years ago #
JavaWizKid
Member

No that's not the problem :( I just made a demo to test the theory. I don't see where the problem is. Basically the menu system all works together eg: Main menu, instructions, play game etc. When the game scene is loaded, threads are started and graphics moved etc etc, intense stuff :) When it is game over a UIAlertView appears asking do you want to play again or go back to the menu. If you click play again, it works and the threads etc are reloaded. No problems. However the return to menu button keeps everything stopped eg threads and then tries to replace the screen with the menu. It succeeds for about 1 second and crashes. Is it something to do with all the thread and images still existing and not being destroyed when the scene switches? What exactly does cocos2d do when it comes to switching scenes? Does it remove the previous one and destroy everything or just lay the new layer on top like a sandwich? Thanks.

Posted 2 years ago #
bradparks
Member

total guess, but I'd say you've got a schedule still running.. complete guess though... if you do, unschedule it in the onExit of the scene... do you have any schedules that are about 2 seconds long?

Posted 2 years ago #
JavaWizKid
Member

When do you run the onExit function? I stop the thread when I show the UIAlertView. Does this keep them stopped when the scene gets replaced? Thanks

Posted 2 years ago #
JavaWizKid
Member

I've tried releasing EVERYTHING and then deleted the ones you NEED to have unreleased such as touch events. Crash persists. When UIAlertView function is chosen I release everything that hasn't been 'noded' :) because if I do with the code [self removeChild:longPlatform cleanup:YES]; it errors. Anyway according to the console there are NO errors unless ran in debug mode :S The only debug mode error is 'EXC_BAD_ACCESS'. Any suggestions? Maybe the error is to do with UIAlertView and switching scenes with cocos2d transitions? No Just tried it without UIAlertView. I can' see where the crash is coming from! Very annoying. I don't want to abandon the ability to return to the main menu from the game scene!

Posted 2 years ago #
JavaWizKid
Member

Sorry for excessive posting. I think I have the proper reason for the error :) Basically I have a MotionLayer as a Child of GameScene. I'm calling the change scene function from the MotionLayer which is a child of GameScene and because of this I think the action is impossible as it doesn't see the other layers apart from its parent which is GameScene. How can I call the change scene function THROUGH it's parent GameScene and defeat the error! :) Thanks very much!

CRACKED IT. I followed some quide to turn on zombie tracing and found the issue was deallocating an object which 'apparently' was trying to be accessed, I looked at my code and it wasn't so I just shut off super dealloc. Job done :)

Posted 2 years ago #
x0661t
Member

Hello, i have the same issue, i turned off [super dealloc], but now it reacts at touches on previous layer, any ideas?

P.S. it's exaclty same issue :(

Posted 1 year ago #
x0661t
Member

btw, i'm using cocos2d v0.9.0 beta2 now.

Posted 1 year ago #
x0661t
Member

anyone?

Posted 1 year ago #
riq
Key Master

@x0661t: I suggest updating to v0.99. It contains some fixes related to replaceScene

Posted 1 year ago #
x0661t
Member

@riq: it doesn't help :( any suggestions?

Posted 1 year ago #
nomore
Member

I had the same issue. I've just recently started with cocos2d, but I found out what the problem was for me.

When using the CCDirector replaceScene method - it has a loop that goes through the child node objects (sprites etc.).

Look in CCNode's dealloc method:

for (CCNode *child in children_) { child.parent = nil; }

What I was doing was releasing the sprites in my layer's dealloc method, and then then it calls [super dealloc], the references in children_ are still there, but are considered 'out of scope'. This causes a crash.

The code in CCNode then calls:

[children_ release];

So... CCNode's dealloc method takes care of cleaning up child objects that were added with CCNode's addChild: method.

I guess it could be a bit more robust.

Posted 1 year ago #
piercer
Member

Exactly the same issue for me - I was being good with my memory management but its seems that cocos2d wants to clean up for me too. I am not sure I like this.

Posted 1 year ago #
riq
Key Master

replaceScene releases the retained objects.
Perhaps you are deallocing the objects more than once ?

Posted 1 year ago #
Winder
Member

I had this issue and it was due to misuse of properties.

I had a particle emitter property and used it as follows:
emitter = [CCParticleFire node];

The error was because I didn't use self.emitter so it was never actually retained, when dealloc came and I called release there the object was deleted, then when cocos came along and tried to decrement its retain the error occurs!

You can troubleshoot which of your properties is doing this by commenting out all of the your releases in dealloc then uncommenting them one at a time.

Posted 1 year ago #
dany
Member

Thanks Winder, really usefull post, i had solved the same problem in few minutes :D

Posted 1 year ago #

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