Scheduling a CCTimer for a single run with delayed execution

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Scheduling a CCTimer for a single run with delayed execution

(7 posts) (5 voices)

Started 2 years ago by vargonian
Latest reply from Blue Ether

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vargonian
Member

Hi,
I'm having issues when I try to schedule timers to run *once*, but after a few seconds. For example, if I have:

[self schedule:@selector(spawnHero) interval:5.0f repeat:0];

..in my layer's init method, I expect to be saying "Call spawnHero after 5 seconds, then don't call it ever again." But instead, what appears to be happening is that this timer is being deferred until later (presumably until the layer is added to the scene and isRunning is YES), but when "later" comes around, the scheduler determines that this timer is past its expiration date and it gets unscheduled before it even had a chance to fire once.

I tried adding this schedule call to onEnter (overridden in my layer class) after calling [super onEnter], but a similar situation happens.

Setting the repeat parameter to 1 causes the timer to fire endlessly for other problematic reasons that I won't get into here.

Posted 2 years ago #
Bongeh
Member

what about having an int with a count of 5, having a scheduler that runs every second, and does count-- if count is >0, else spawnHero. you could also have the spawnHero method unschedule the counter timer as it wont be needed any longer.

Posted 2 years ago #
DetectiveCakes
Member

You may want to take a slightly different approach and use a DelayTime action sequenced with callfunc when you only want to schedule something once:
[self runAction:[Sequence actions:[DelayTime actionWithDuration:5.0f], [CallFunc actionWithTarget:self selector:@selector(spawnHero)], nil]];

Posted 2 years ago #
crmagicxxx
Member
@vargonian

You said you want to "Call spawnHero after 5 seconds, then don't call it ever again."
```
[self schedule:@selector(spawnHero) interval:5.0f repeat:1];
```
Above line does exactly that.
Posted 2 years ago #
vargonian
Member

@crmagicxxx: As I said in my post, calling repeat:1 was causing issues of its own (i.e. sometimes repeating forever), but I will try to pinpoint what those were.

DetectiveCakes: Thank you, I was looking for an action that would do the job for me but couldn't find one. I didn't know that a CallFunc action existed! :)

Posted 2 years ago #
vargonian
Member

I've since verified a couple things:

crmagicxxx was exactly right (as I'm sure he/she knew :) )

The problem I was facing with a repeat count of 1 was related to other code. Essentially the object which called this timer was not getting properly cleaned up, and I was triggering it to call the timer again without realizing it.

Posted 2 years ago #
Blue Ether
Member

I didn't know there was a "repeat" parameter for schedule- is this a 0.9 feature?

I do see a linguistic issue with the use of the tag "repeat" for this parameter, since it implies the selector will be called "1+n" times rather than "n" times. A more straightforward term might be "loops" or even "duration." Though if this parameter is actually boolean, repeat makes sense.

Posted 2 years ago #

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