AS3 Question(s)

[Buff_]

This post by Buff_ was thumbed up by:

Blablob (December 13th, 2012, 1:48 pm)

[Blablob]

Can you explain to me how to use an array properly? I've tried a lot of things and I've looked up a few tutorials but I haven't gotten anywhere.

[Buff_]

An array is basically a list in the same variable name (you can find a much more in depth definition elsewhere).

In Actionscript 3, an array is defined by var [name]:Array, and can be actively made to be used by var [name] = new Array() if it has already been defined. Unlike some other languages you don't have to set the number of items the array can hold, but rather it adds at runtime. Each specific item can be accessed by [name] followed by [num]. So for example, an array called thisArray could have two items in it which can be accessed by using thisArray[0] and thisArray[1]. The numbers go from 0 onwards because computers count on from 0.




or read from adobe's site: http://help.adobe.com/en_US/FlashPlatfo ... Array.html

[Blablob]

Oh, I should have been more specific. I know what an array can do, but I can't figure out how to use it to create a shoot function. And I assume I need to use the [name].push function for that, but I have no idea how.

[Buff_]

This post by Buff_ was thumbed up by:

Blablob (December 15th, 2012, 4:20 pm)

[Blablob]

Well, Buff, whenever you're ready to help me with my code is fine by me. I'm on Holidays now too, so I have a lot of time to mess around with code. I'm hoping to get a little more done than just learn how to shoot bullets. :>

[Blablob]

Okay, so I'm back after a six month hiatus. I haven't coded anything in a few weeks, so I'm a little rusty. Anyways, I'm working on a shooter again (just a small project - I expect to be done by the weekend), but I ran into a bit of a wall again with the shooting. This time I'm trying to use an array to hold all my bullets, but when I try to remove these bullets, I get an error message.

Here is my function which creates and shoots the bullet. For simplicity's sake, I set the boundary to 250 so I could check whether the bullets actually disappear or not.

private function shoot():void
{

var bullet:playerBullet = new playerBullet;
bullet.x = playerShip.x-20;
bullet.y = playerShip.y+40;
container.addChild(bullet);
bulletArray.push(bullet);
bulletCounter = 12;
shootSound.play();

addEventListener(Event.ENTER_FRAME, moveBullet);

function moveBullet(e:Event):void
{
bullet.x += playerBulletSpeed;

if (bulletArray[0].x > 250)
{
container.removeChild(bulletArray[0]);
}
}

}

In case you weren't sure, bulletCounter is what I use to keep the player from shooting.

So, when the first bullet approaches 250x, Flash gives me this error:

ArgumentError: Error #2025: The supplied DisplayObject must be a child of the caller.
at flash.display::DisplayObjectContainer/removeChild()
at MethodInfo-8()

Here's a link to the game if you think it will help. You'll notice the first bullet disappears but the rest pass through the boundary.
http://www.newgrounds.com/dump/item/d31 ... 9cc4605b0b

[Buff_]

You're calling the function to remove the bullet every frame, so that even after it's been removed the value is still beyond 250 and will try to remove a non-existant object.

[Blablob]

I added a removeEventListener to remove the function (I brainfarted and forgot to do that), but it still didn't work. Luckily, I was able to scrape something together to fix the problem. Here's what I did:

function moveBullet(e:Event):void
{
bullet.x += playerBulletSpeed;

if (bullet.x > 250)
{
bulletArray.pop();
container.removeChild(bullet);
removeEventListener(Event.ENTER_FRAME, moveBullet);
}
}

[Runouw]

This post by Runouw was thumbed up by: 2

Blablob (June 5th, 2013, 2:59 pm) • Killswitch (June 6th, 2013, 2:38 am)