Scheduled update method stops being called after resume

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Scheduled update method stops being called after resume

(22 posts) (5 voices)

Started 5 months ago by nocivus
Latest reply from rsanchezsaez

Tags:

nocivus
Member

Hi all,

For some reason, when i switch from my app to another one and then back the scheduled update method stops being called.

In my scene's init i'm doing:

[self scheduleUpdate];

And i've declared the update method, which is called correctly when the application first starts:

- (void)update:(ccTime)dt {
    NSLog(@"%f", dt);
    [watch increaseTime:dt];
}

But when i press the home button and go back to the application it stops being called (i.e i stop seeing messages in NSLog).

Here are my AppDelegate methods regarding resume/pause/etc:

- (void)applicationWillResignActive:(UIApplication *)application {
    [[CCDirector sharedDirector] pause];
    [[[CCDirector sharedDirector] runningScene] pauseSchedulerAndActions];
}
- (void)applicationDidBecomeActive:(UIApplication *)application {
    [[CCDirector sharedDirector] replaceScene:self.menuScene];
    [[CCDirector sharedDirector] resume];
}
- (void)applicationDidReceiveMemoryWarning:(UIApplication *)application {
    [[CCDirector sharedDirector] purgeCachedData];
}
- (void)applicationDidEnterBackground:(UIApplication *)application {
    [[CCDirector sharedDirector] stopAnimation];
}
- (void)applicationWillEnterForeground:(UIApplication *)application {
    [[CCDirector sharedDirector] startAnimation];
}
- (void)applicationWillTerminate:(UIApplication *)application {
    [GameCenterManager saveState];
    CCDirector *director = [CCDirector sharedDirector];
    [[director view] removeFromSuperview];
    [viewController_ release];
    [window_ release];
    [director end];
}
- (void)applicationSignificantTimeChange:(UIApplication *)application {
    [[CCDirector sharedDirector] setNextDeltaTimeZero:YES];
}

Am i doing something wrong? Is it a bug in Cocos? Any ideas?

Thanks in advance,
Pedro

Posted 5 months ago #

nocivus
Member

Anyone?

Posted 4 months ago #
Karl
Member

Why are you calling replaceScene in applicationDidBecomeActive? That will make it replace the scene (and lose the old one) every time you switch apps.

Posted 4 months ago #
nocivus
Member

If I do it with push scene and pop scene the actions on the menu items no longer work when coming back from other apps...

Posted 4 months ago #
Scryb
Member

But why are you changing the running scene when leaving the game?

Posted 4 months ago #
nocivus
Member

Because i want the game to be back on the menu (pause) when the user comes back.

Posted 4 months ago #
Birkemose
Moderator

You should stop scheduled updates onExit, and reschedule them onEnter.

Posted 4 months ago #
Karl
Member

You are calling pauseSchedulerAndActions and not calling resumeSchedulerAndActions.

Posted 4 months ago #
nocivus
Member

I call the resume scheduler on the menuScene, after pressing play again (code not here)

Posted 4 months ago #
nocivus
Member

@Birkemose what's the point of having pause/resume support if you need to reschedule updates every time?

In any case, this apparently has been solved on version 2 (source code). But now when i come back to the menu, the menu items no longer trigger any calls :(

Posted 4 months ago #
Birkemose
Moderator

@nocivus
The idea of pausing and resuming schedulers, are to pause and resume the schedulers. I thought that was pretty obvious.
When you switch scenes, as you do, you will have to disable / enable touch, accelerometer, and scheduled events, and besides that, you don't need to pause schedulers when pushing the app to background.

Posted 4 months ago #
nocivus
Member

Let me try to explain my app a bit: I have a scene that consists on a geometric figure appearing after a certain (random) amount of time, and measuring the time it takes the user to touch it. Now, i need a scheduler to control the appearance of the figure (which gets reset when the user touches it) and a stopwatch (incremented by the scheduled nextFrame call on init of the scene) that is reset when the figure appears.

I was under the impression that the scheduling mechanism stored the scheduled calls and their state and that the pause would simply "freeze" them until such time when i wanted to resume the whole thing. Actually, this is what is now happening in v2 beta (source code) and sounds right to me.

So, bottom line, my issue now is not the pausing and resuming of the schedulers. My problem now is that the actions of the menu items no longer trigger the respective methods when i push the menu scene into the director. Any ideas on that?

Btw, thank you all for the input so far :)

Posted 4 months ago #

Karl
Member

Here's a quick app that does what you want, I think: http://www.mediafire.com/?p15vaj98y7twctc

Salient points:

AppDelegate.m:

- (void)applicationWillResignActive:(UIApplication *)application {
	CCScene* scene = [CCScene node];
	[scene addChild:[MenuLayer node]];
	[[CCDirector sharedDirector] pushScene:scene];
	[[CCDirector sharedDirector] pause];
}

- (void)applicationDidBecomeActive:(UIApplication *)application {
	[[CCDirector sharedDirector] resume];
}

- (void)applicationDidReceiveMemoryWarning:(UIApplication *)application {
	[[CCDirector sharedDirector] purgeCachedData];
}

-(void) applicationDidEnterBackground:(UIApplication*)application {
	[[CCDirector sharedDirector] stopAnimation];
}

-(void) applicationWillEnterForeground:(UIApplication*)application {
	[[CCDirector sharedDirector] startAnimation];
}

HelloWorldLayer.m:

-(id) init
{
    ...

        [self scheduleUpdate];
    ...
}

- (void) update:(ccTime)dt
{
    _totalTime += dt;
    NSLog(@"Update %.3f", _totalTime);
}

MenuLayer.m:

- (id) init
{
    if((self = [super init]))
    {
        CCMenu* menu = [CCMenu menuWithItems:
                        [CCMenuItemFont itemFromString:@"Do Something" target:self selector:@selector(doSomething)],
                        [CCMenuItemFont itemFromString:@"Return" target:self selector:@selector(onReturn)],
                        nil];
        [menu alignItemsVertically];
        [self addChild:menu];
    }
    return self;
}

- (void) doSomething
{
    NSLog(@"Something");
}

- (void) onReturn
{
    [[CCDirector sharedDirector] popScene];
}

It stops counting when the app is backgrounded. Once the app is brought back, it immediately pushes a menu scene. Upon dismissing the menu scene (via "Return" in the menu), it resumes counting where it left off in HelloWorldScene.

Posted 4 months ago #

nocivus
Member

Thanks! Will give it a try and compare where i might have gone wrong :)

Posted 4 months ago #
nocivus
Member

Just a quick question, though... Do you need to instantiate a new menu scene every time?

Posted 4 months ago #
Karl
Member

Yes. When you popScene, it pops and releases whatever scene is currently running. You could try saving it somewhere before popping, but it's probably not worth it. Optimizing before a profiler tells you there's a bottleneck just paints you into a corner later by making your code overly complex.

Posted 4 months ago #
nocivus
Member

Understood. Thanks a lot for the info :)

Posted 4 months ago #
nocivus
Member

Just one last question, since you seem to be a cocos2d guru :) Any idea why gamecenter would not record any leaderboard values? I have it set up properly (me thinks) and the call to store the value does not throw an error. But when i look at the leaderboard i get no entries. I read somewhere that it could take some time for them to appear, but it has been over 2 weeks now... :(

Posted 4 months ago #
Birkemose
Moderator

I havent tried v2 yet, but in v1, there is no difference to you if you pause or remove the scheduled event ( other than some code overhead ). There are no "frozen" states saved, pause is just a flag telling the scheduler not to call your selector. It also sounds like you have more than one scheduled event, and that you start and stop them based on functionality.
You could either use actions, or you could use one continuously running scheduler, and maintain a small state machine.

Like I s aid, you really dont need to pause stuff when your app is pushed to background. Cocos2D will do all the hard work for you.

Posted 4 months ago #
Karl
Member
Hmm.. if it's not there after 2 weeks that's definitely a problem!

Game Center is very unforgiving of things done wrong. Even getting the case of your identifiers wrong will cause Game Center to ignore you (It won't even give error messages). If you have it set up correctly, it should take no more than half an hour for your stats to show up, and usually far less than that (like 1 minute tops).

Reporting should look something like this:
```
GKScore *scoreReporter = [[[GKScore alloc] initWithCategory:category] autorelease];
    scoreReporter.value = score;

    [scoreReporter reportScoreWithCompletionHandler:^(NSError *error) {
		if (error != nil)
		{
            // handle the reporting error
			LOG_ERROR(@"%s: Failed: %@", __PRETTY_FUNCTION__, error);
        }
    }];
```
Edit: Also check your game center settings in iTunes Connect very carefully. Once again, it's very unforgiving.
Posted 4 months ago #
nocivus
Member

Seems to be similar to what i'm doing, though i'm tracking the ones that are not submitted in an array (so they can be submitted later). However, i've noticed that it does indeed get submitted. Have to look further into it :(

Posted 4 months ago #
rsanchezsaez
Member

Quote: 'You should stop scheduled updates onExit, and reschedule them onEnter."

Birkemose: Why is that? If I am understanding it right, cocos2d's onExit calls 'pauseSchedulerAndActions' and onEnter resumes them again. What's the benefit of stopping scheduled updates and rescheduling them again?.

I usually call [scheduleUpdate] on init and everything seems to work fine.

Posted 3 months ago #

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