[As3] Variable name from another variable

[Broly]

Hi all,
I'm new in this forum :)
I've a problem in the Actionscript 3 Flash 9 Alpha.

I'm trying to give to a variable a name taken from another variable, for example

a = "pippo"
this[a] = 10
trace(pippo)

and this

b=1
this["pippo"+b] = 10
trace(pippo1)

works in Actionscript 2...but it doesn't work in Actionscript 3.
I tried in many ways but it doesn't work :(

Any help will be appreciated :)

Thanks!

[TheCanadian]

var a = "pippo"
this[a] = 10
trace(this.pippo)



var b=1
this["pippo"+b] = 10
trace(this.pippo1)

[Broly]

ActionScript Code:

var a = "pippo"
this[a] = 10
trace(this.pippo)



var b=1
this["pippo"+b] = 10
trace(this.pippo1)





Oh My God...

After your post, I made two considerations/conclusions.

1) I need holidays
2) I've to kill myself

Now I go to make my choice between two options...

Thanks The Canadian...and excuse for the stupid question :look:

[TheCanadian]

:lol: No problem.

[Tigerfisk]

Hello, sorry for this big buuump. But i have a following questions to what was written before.

I want to make a variable from another variable.
Example


var number:int= new int(1);
this["enemy"+number]; <--- (is this needed?)

var ["enemy" +number]:MovieClip = new MovieClip(); <-- i know this is wrong.
I want to make variables like enemy1, enemy2, enemy3...


But I have no idea what I am doing wrong. Can this be solved?
Thanks in advance.
// Olof

[Valaran]

You cannot create single variable names from another variable straight off the bat, the thing you can do, like shown before, is add a variable to a dynamic display object, like the MovieClip, an object, like the following:


// Example one:
var enemies:Object = {};
var num:int = 0;
var str:String = "enemy" + num;
var clip:MovieClip = new MovieClip();

enemies[str] = clip;

// Example two, you could skip the entire string and use an array:
var enemies:Array = [];
var clip:MovieClip = new MovieClip();
enemies.push(clip);

[Tigerfisk]

Hello. i think the example 2 is better in this case. But i cant get it really to work.

I am to learn flash and make a "eskiv" clone.
If you dont know what eskiv is, Play it here. http://www.arcadecabin.com/play/eskiv.html


I show parts of the code so you can understand easily.
(Swedish to English translate)
Fiende = enemy
Fiender = enemies
this is in the top of the code.



var uppellerner:Array=new Array();

var fiender:Array=new Array();
var fiende:MovieClip = new MovieClip();
fiende.graphics.beginFill(0x8B1A0E);
fiende.graphics.drawCircle(70,60,6);
fiende.graphics.endFill();
fiende.x = 80;
fiende.y = 60;
fiender.push(fiende); // adds fiende to an array. But dont know what to do with it
uppellerner.push("true");
addChild(fiende);
This works on the firstball i add to the game. But on ball 2 the movieclip needs another name.

And this is in the everyframe function


while (i < uppellerner.length) {
whiletrue = uppellerner[i];

if (whiletrue == "true") {
fiende.y-=datorfart;

}
if ( whiletrue == "false") {

fiende.y+=datorfart;

}
if (fiende.hitTestObject(topp) ) {
whiletrue = "false";

}
if (fiende.hitTestObject(bottom) ) {
whiletrue = "true";

}
uppellerner[i] = whiletrue;
i++;
}
}
Same here, The first ball moves perferct.


Full fla file http://oloflolof.se/arkiv/trendo1314.rar


I hope someone there is someone who can help me.
Thanks in advance
// Olof

[Tigerfisk]

I have tried a little more with arrays now.
This code creates 2 balls and put in array. But the problem is still that both have the same movieclip name.

And the "while" as you see further down, just a ball and coordinates the ball two would have.



var fiende:MovieClip = new MovieClip();

//create ball 1
fiende.graphics.beginFill(0x8B1A0E);
fiende.graphics.drawCircle(70,60,6);
fiende.graphics.endFill();
fiende.x = 80;
fiende.y = 60;
fiender.push(fiende);
uppellerner.push("true");

//create ball 2
fiende.graphics.beginFill(0x8B1A0E);
fiende.graphics.drawCircle(70,60,6);
fiende.graphics.endFill();
fiende.x = 180;
fiende.y = 60;
fiender.push(fiende);
uppellerner.push("true");

var o:int = new int(0);
while( o < fiender.length){
addChild(fiender[o]);
o++
}

[Valaran]

Looopy loopy! Instead of doing it all manually, since we are already using arrays, you should just loop through it all, I haven't tested this, but I think it should run :P


// Adding everything
var fiender:Array = [];

var totalLen:int = 20;
for(var i:int = 0; i < totalLen; i++)
{
// At this time, I'm not sure what your "uppellerner" array holds, but I'm gonna guess it
//decides if the enemy is moving up or down, so I'm gonna show you one of many better
//ways to deal with it:
var fiende:MovieClip = new MovieClip();
fiende.x = 80 + i * 100;
fiende.y = 60;
var obj:Object = { clip:fiende, direction:true };
fiender.push(fiende);
}

// Run on every frame

var enemyLen:int = fiender.length;

for(var i:int = 0; i < enemyLen; i++)
{
var check:Boolean = fiender[i].direction;

// Ternary statement, the same as an IF, can only have 1 statement if evaluated true and one if false
// (check)? is the same as if(check){
// and the : (semicolons) are the same as } else {
fiender[i].y = (check)? fiender[i].y - datorfart : fiender[i].x + datorfart;

if(fiender[i].hitTestObject(topp))
{
check = true;
}
else
{
// Only need to check this if the above one returns false
// The object can't be at two points at the same time after all!
if(fiender[i].hitTestObject(bottom)) check = false;
}

fiender[i].direction = check;
}

[Tigerfisk]

Hi again Valaran.


I am really glad that someone helps me and appreciatte everything you do for me.
I added this in the beginning so i could see the balls.


fiende.graphics.beginFill(0x8B1A0E);
fiende.graphics.drawCircle(70,60,6);
fiende.graphics.endFill();
And edited this so the ball was moving


fiender[i].y = (check)? fiender[i].y -=datorfart : fiender[i].x +=datorfart;
But now i got more problems...


This is how the script works now:
Adds a number of balls.
But they do not roll straight down without a little wrong.
And they do not bounce back against the wall.

I think it is something in this code.
fiender[i].y = (check)? fiender[i].y -=datorfart : fiender[i].x +=datorfart;

Live demo: http://oloflolof.se/arkiv/trendobollarullarinterakt.swf


Thanks in advance
// Olof

[Tigerfisk]

edit:

I changed the if to the orginell way and now is it working. :P

if(fiender[i].direction == true){
fiender[i].y += datorfart;
}
else if(fiender[i].direction == false){
fiender[i].y -= datorfart;
}

Will test it more now and i will write here if its works or not when i am done. :)

[Valaran]

If you hadn't changed my ternary statement, it would had worked just like the if-statement..

[Tigerfisk]

If you hadn't changed my ternary statement, it would had worked just like the if-statement..


You mean this code?


fiender[i].y = (check)? fiender[i].y - datorfart : fiender[i].x + datorfart;

The ball was not moving with that code.

[Valaran]

That is very strange, since:


fiender[i].y -= datorfart;

// is exactly the same as

fiender[i].y = fiender[i].y - datorfart;

// So this:

fiender[i].y = fiender[i].y -= datorfart

// is basically

fiender[i].y = fiender[i].y = fiender[i].y - datorfart;


Makes no sense at all, well nevermind, use whatever works for you.

[Tigerfisk]

Yeah i know, Its weird.

Anyway, i have a new problen now.

if the blueball (player) hits an enemie i want all enemies to disapear.

Code


var enemyLen:int = fiender.length;
// the first for to loop out all enemies
for (var i:int = 0; i < enemyLen; i++) {
var ledboolean:Boolean = fiender[i].direction;
addChild(fiender[i]);

if (ball.hitTestObject(fiender[i])) {
lost=1;
// second for to loop out all enemies again to remove them.
for (var o:int = 0; o < enemyLen; o++) {

removeChild(fiender[o]);

}
... the enemieball movement code.
}

But the problem is...


Pretend that there are two enemy balls in the game...
If you hit ball1, only ball1 disappears. But if i hit ball2 bothdisappears.
Weird.



The reason I want to do this is when the player will restart a game when the player lost.
Otherwise will the red balls remain in the game.
Thanks!

Olof



(This issue is a bit offtopic than what I ask before, you may think I should start a new thread? )



EDIT:

Yay! Moved the for to a function outside the everyframe function and now is's working!

[Matthew Lueck]

What better way to introduce myself to the forums than with a necropost.


fiender[i].y = (check)? fiender[i].y - datorfart : fiender[i].x + datorfart;

I came across this thread while looking for something else and figured it'd be a good idea to explain why this code wouldn't work. The value if false adds the x property instead of the y. ;)

The ternary statement itself should be fine. Wiki explains it in-depth here (http://en.wikipedia.org/wiki/Ternary_operation), but I'll give a quick explanation in relation to ActionScript.

If/Else statement:

if (logical test) {
var = value if true;
} else {
var = value if false;
}

Ternary statement (essentially shorthand):

var = (logical test) ? value if true : value if false;

The main benefit for me to using ternary statements is the leaner code. I can declare a variable and set its value all on a single line. Ternary statements aren't just limited to variable declarations either.

Dynamic tracing:

trace("This movie clip is " + ( (mc.alpha > 0) ? "shown" : "hidden" ) + ".");
// Alpha is greater than 0: "This movie clip is shown."
// Alpha is less than or equal to 0: "This movie clip is hidden."

Functions on event listeners:

var toggleButton:ToggleButton= new ToggleButton(); // Library asset or external class.
toggleButton.toggled = true; // Custom property on ToggleButton.
toggleButton.addEventListener(MouseEvent.CLICK, function() {
(toggleButton.toggled) ? toggleButton.toggled = false : toggleButton.toggled = true;
}); // The button to switches the toggled property between true and false when clicked.

[nook]

Hej Tigerfisk.

From one Swede to another, I strongly recommend you to start using ONLY english in your code.