how to set a maximum size for ArrayList?

Programming Questions

dori

how to set a maximum size for ArrayList?

in Programming Questions • 5 months ago

Hello all,

I m creating a particles system, with array list, i want to add particles but when they get to 100 i want them to die.

How to do it.

can i limit this function:

particles.add(new Particle(origin));

Tnx allot!

Replies(11)

amnon.owed

Re: how to set a maximum size for ArrayList?

5 months ago

Use an if statement and the size() of the ArrayList.

dori

Re: Re: how to set a maximum size for ArrayList?

5 months ago

thanks for the answer, i m pretty new to this processing world, so maybe i dont understand it well.

but, i m trying to do it and it doesnt work,

is it right to use in the statement .remove();

like this:

particles.add(new Particle(origin));

if (particles.size >= 100){

particles.remove();

}

tnx!!

amnon.owed

Re: how to set a maximum size for ArrayList?

5 months ago

You could do that. Or you could put it around the add statement.

if (particles.size() < 100){
particles.add(new Particle(origin));
}

dori

Re: Re: how to set a maximum size for ArrayList?

5 months ago

Thanks allot Amnon!

it really helped me!!

but, now i have a new problem (only if u have time to check it..)

i m using control p5 and each time i m releasing different particles. I want to create different particle.size for each one of them. is it possible?

this part of my script look like this now:

void addParticle() {
if (gas_0==true) {
if (particles.size() < 100) {
particles.add(new Particle(origin));
}
}
if (gas_1==true) {
if (particles.size() < 10) {
particles.add(new Gas_1(origin));
}
}
if (gas_2==true) {
if (particles.size() < 50) {
particles.add(new Gas_2(origin));
}
}
if (gas_3==true) {
if (particles.size() < 200) {
particles.add(new Gas_3(origin));
}
}
if (gas_4==true) {
if (particles.size() < 50) {
particles.add(new Gas_4(origin));
}
}
}

GoToLoop

Re: how to set a maximum size for ArrayList?

5 months ago

To individually control the maximum entries for each type of an instantiated class,

you're gonna need individual counters for each one!

Method size() only returns total # of entries from a Collection.

It can't count how many entries for each kind!

dori

Re: Re: how to set a maximum size for ArrayList?

5 months ago

Thanks for the answer!!

yes, i understand the size() problem.

I ll tray to set a counter, hope i ll manage it.

i will update as it goes..

Tnx!

dori

Re: how to set a maximum size for ArrayList?

5 months ago

ok.. GoToLoop.. i dont succeed to set it.. do u have a suggestion how to attack it?

Chrisir

Re: how to set a maximum size for ArrayList?

5 months ago

when you have a class
put the counter there in.

So each particle has its own counter because their age is all different.

(Don't have a global counter)

in draw() increase the counters for all particles.
Kill particles with a counter >100

dori

Re: Re: how to set a maximum size for ArrayList?

5 months ago

thanks Chrisir.

but, i dont want to kill the particles, i just want to add diffrent amounts.

that means- i want to click a button that adds 50 for one class, 100 for other class..

Chrisir

Re: how to set a maximum size for ArrayList?

5 months ago

can't you use a for-loop and say in that for-loop

particles.add(new Gas_4(origin));

and for

one button make the loop up to 20
for the next button up to 50 and so on?

dori

Re: how to set a maximum size for ArrayList?

5 months ago

I will tray it!

tnx.

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