Difference between revisions of "User talk:Awesomeness"

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:: Be sure don't use for-each style (<code>for(Bullet bullet : bullets)</code> or you will get ConcurentModificationException when you remove element (this is per java spec, but I still use the for-each style and didn't get this exception actually). And when you scroll through the array like one I mentioned, be sure you do i--, or you will just skip one element. &raquo; <span style="font-size:0.9em;color:darkgreen;">[[User:Nat|Nat]] | [[User_talk:Nat|Talk]]</span> &raquo; 14:19, 2 May 2009 (UTC)
 
:: Be sure don't use for-each style (<code>for(Bullet bullet : bullets)</code> or you will get ConcurentModificationException when you remove element (this is per java spec, but I still use the for-each style and didn't get this exception actually). And when you scroll through the array like one I mentioned, be sure you do i--, or you will just skip one element. &raquo; <span style="font-size:0.9em;color:darkgreen;">[[User:Nat|Nat]] | [[User_talk:Nat|Talk]]</span> &raquo; 14:19, 2 May 2009 (UTC)
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:: Oh, you're right.  [[User:Awesomeness|Awesomeness]] 14:27, 2 May 2009 (UTC)
 
:: Oh, you're right.  [[User:Awesomeness|Awesomeness]] 14:27, 2 May 2009 (UTC)

Revision as of 15:27, 2 May 2009

Archived talks:
Archived Talk 20090502

Okay, I need to make a list of bullets. I have made a bullet class and everything, but I need a special list that will let me access all of the bullets in a while/for loop and be able to add and remove them at any time and never mess up. If I did this in a normal array I could do a for loop and access using an increasing number, but I wouldn't know when to stop. In a while loop, if I used while(bulletsArray[x] != null) and then increment x, after I remove my first bullet that say, hit a wall, it will stop there. I need help!

Thanks,
Awesomeness 14:02, 2 May 2009 (UTC)

I think this will do:

ArrayList<Bullet> bullets = new ArrayList<Bullet>();
for (int i = 0; i < bullets.size(); i++) {
    Bullet bullet = bullets.get(i);
    if (bullet.needRemove()) {
        // I think this will work
        // bullets.remove(i--);
        // but usually I do
        bullets.remove(bullet);
        i--;
    }
}

Here I assume that you use ArrayList to store you bullets and your bullet's classname is Bullet. If you use a plain array to keep the bullets, consider change to ArrayList. It is more flexible. » Nat | Talk » 14:09, 2 May 2009 (UTC)

Oh my gosh! You're right! ArrayList is way more flexible! I looked at the documentation; you don't even have to increment or decrement anything! The function remove() shifts the other elements to the left already! Thanks! Awesomeness 14:14, 2 May 2009 (UTC)
Be sure don't use for-each style (for(Bullet bullet : bullets) or you will get ConcurentModificationException when you remove element (this is per java spec, but I still use the for-each style and didn't get this exception actually). And when you scroll through the array like one I mentioned, be sure you do i--, or you will just skip one element. » Nat | Talk » 14:19, 2 May 2009 (UTC)
Oh, you're right. Awesomeness 14:27, 2 May 2009 (UTC)