So I've spent an embarrassing number of hours trying to save myself a few minutes and make my code a bit neater, and Google has produced nothing, so now I come crawling to stackoverflow. The problem is with square bracket notation + library items:
So let's say you have a MovieClip called "myMC_5", and you want to set its X position to 0..
myMC_5.x = 0;
..and if you don't want to hard-code the name of the MC but instead you want one line of code to move a specific MovieClip based on a variable, you could do something like this:
var selectMC = 5;
root["myMC_"+selectMC]x = 0;
..and this will have the exact same effect as myMC_5.x = 0, except that this time you must specify the location ("root" or "this" or something).
THE PROBLEM:
I'm working on a game in which the graphic for the background is loaded from the library, and it's different for each level. The initial loading of the vector from the library looks like this:
private var land:vector_land0 = new vector_land0();
..and this works fine, but it only loads that one specific vector. There should be about 30 or more. I'd like to just have 1 line of code in the constructor to load any of them, based on a variable which keeps track of the current level, like this:
private var land:["vector_land"+theLevel] = new ["vector_land"+theLevel]();
..but that doesn't work. I get syntax errors ("expecting identifier before leftbracket") because you need to specify the location of the object, like in the first example:
root["myMC_"+"whatever"].x = 0;
..but this library item has no "location". So, how the heck do I dynamically load a vector from the library? It's not "on the root", or anywhere else. It has no location. I refuse to believe that the standard method for accomplishing this is to create 30 different classes or write a giant block of code with 30 "if" statements, but searching Google has found nothing. :(
It sounds like you're looking for getDefinitionByName(), which you could use to do something like this:
import flash.utils.getDefinitionByName;
private var LevelVectorClass:Class = getDefinitionByName("vector_land" + theLevel) as Class;
private var land:Object = new LevelVectorClass();
This is a horrible way to solve the situation, I don't recommend using square brackets anywhere but arrays. I recommend you putting the "lands" into a LandContainer MovieClip, each frame of that MovieClip would container 1 graphic. It is much cleaner, and you could create constants to store the "identity" of the frames.Example:
var land:LandContainer = new LandContainer();
land.gotoAndStop(FIRST_LEVEL); //FIRST_LEVEL is a constant integer
You can even reuse this LandContainer instance because you can set it's visibility, remove from the display list, set it's frame to the next level without creating another instance. On second thought, I would write a wrapper for this class. Aka link it to your own class which extends the MovieClip class and create custom functions, fields... etc..
This dynamic thing is horrible, hard to maintain, and not efficient at all. Don't know why did not they delete it from AS3... they should have.
Related
I'm creating flash game. Here will be abillity to choose one of two (or more) character's. So I have in library created symbol hero. It have 7 animations on click (moving, jumping, attacking etc..)
So I want to create something like hero 2, that player could choose which one likes more. Just how to do that? Create new layer in hero and add animations or how?
I'm asking that because in Action Script 3 I'm adding hero in this case and It always will add the same:
private function create_hero()
{
addChild(Hero);
Hero.gotoAndStop("stay");
Hero.x = stage.stageWidth/2;;
Hero.y = ground.y - 60;
Hero.x_speed = 0;
Hero.y_speed = 0;
}
Maybe here is abillity to make something like that layer2.addChild(Hero);?
Or I need to create new symbol hero2? I don't like this idea, because I have long code to control hero, so for every character I'll need to dublicate code. Could you help me? Thank you.
The proper way is to dynamically create an instance Hero at game start based on the game player's selection. You indeed create two (or more) symbols in Flash CS, with common frame labeling (you can use different animation lengths for different heroes), then, once you've got your hero selection (hero1,hero2,hero3 etc, regardless of their amount) you get the class name from selection and get your Hero variable to be assigned an instance of the respective class. An example:
static var heroes:Array=[hero1,hero2,hero3]; // note: symbol names!
var Hero:MovieClip; // note, not "hero1" or anything, but general MovieClip type
public function selectHero(what:int):void {
// this is called with correct "what", design yourself. I use array index
var whatHero:Class = heroes[what]; // get selected hero symbol
if (Hero && Hero.parent) Hero.parent.removeChild(Hero);
// clean up previous hero. Drop listeners here, if any
Hero = new whatHero(); // get new hero
// process as usual, don't forget to "addChild(Hero)" somewhere
}
How this works: First, you give the player a hero selection dialogue, and call selectHero with proper value of what (0 for hero1, 1 for hero2, etc, as you make your heroes array). Then, the whatHero variable is assigned the corresponding class (yes, one can assign classes to variables in AS3!) And then the class gets instantiated via new construction, and the resultant movie clip is then assigned to Hero variable. After this is done, you can use your hero as before.
Confusing title, my bad.
Basically, I have a list of names. Looping through, I add a MovieClip, Set 2 properties to it, the name, and an ID. The MovieClip is at the same time made to function as a button and I add 4 listeners, mouse up, over, down, or out. I do this with every name. The function each one is set to is the same.
EX: enemyButton[i].addEventListener(MouseEvent.MOUSE_UP, mouseUpHandler);
The enemyID turns up "not valid property," time to time when I click, it doesn't crash at all, but sometimes I have to hit the button a few times.
I have narrowed the problem down to having to be caused by the listeners.
The function as simple as:
EX: function mouseUpHandler(e:MouseEvent):void { enemySelected(e.target.enemyID); }
My question is, is too many listeners likely to be the problem? and how can I reduce them?
Here's a snippet of the loop:
var C:Class = Class(getDefinitionByName(enemies[i]));
var c:* = new C();
c.gotoAndStop(1);
enemyButton[i].enemyID = i;
c.name = "select" + i;
c.enemyID = i;
trace(c.enemyID);
enemyButton[i].addChild(c);
enemyScroll.addChild(enemyButton[i]);
enemyButton[i].enemyName.text = info[i][Const.NAME];
enemyButton[i].setChildIndex(enemyButton[i].getChildByName("enemyName"), enemyButton[i].numChildren-1);
Thanks.
If enemyButton is a MovieClip (created via attachMovie, maybe) and not strongly typed as a EnemyButton class, then the ID property becomes dynamic. In this situation, if your list of names contains incorrect data (missing ID field, maybe), then the ID property will remain undefined on some instances of the MovieClip.
You can check the list of data used to generate movie clips. You can run into the same error if you have blank lines in your data.
This has nothing to do with event listeners.
So you just want to generate a bunch of buttons with unique properties and know what button was clicked last. Generally it is very bad idea to implement button logic outside button object. Why? Because you work with object oriented language. Good news is that you work with as3 and it treats functions as objects, so you can assign function to var like this:
var callback:Function = function(name:String, enemyId:int){ /*do something*/ }
And.. you can pass function as a parameter to another function
function setCalback(func:Function){}
button.setCallback(callback);
So, what you really need is to create your own button class, add listeners inside it, add handlers(static handlers will reduce memory usage) and pass callback function to it, that will be called when user clicks button.
Don't mean to spam this much but this was easily fixed, though the responses might have been a better method.
I just had to change target to the currentTarget, that then allowed clicking anywhere on the "button" to work. Whereas before the target varied from childs added to it.
So, solved.
Thanks for the help.
Current my code is as such
setcustomlocation.addEventListener(MouseEvent.CLICK,customlocation2);
function customlocation2(e:MouseEvent):void
{
locationinput.text = FlashingWon.Won1.name.text;
}
I'm trying to make it such that it would copy the input text field values into a dynamic text. However, it throws up the error that
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at main/customlocation2()[main::frame1:9]
Which can I only assume that it is not able to communicate with the dynamic text field in the movieclip within another movieclip.
First, you can be 100% sure that it CAN communicate with the dynamic TextField in the MovieClip.
From you description I understand that you wish to copy from input into dynamic. But from your code I see that you take from the dynamic into the input, please check that out:
// This will copy in such a way: input <= wonText
locationinput.text = FlashingWon.Won1.name.text;
// This will copy from input
FlashingWon.Won1.name.text = locationinput.text;
Anyhow, the error that you get has nothing to do with this, it's rather like you already noticed, that one of your TextField is not 'found'. For this I recommend you a best practice: To create instances of the objects you want to use and populate them from the stage through the getChildByName method. This way you will promptly now (specially if you do this on construction or init) if you had any misspelling or miss structure on the childs you want to get.
like so:
var inputText: TextField;
var dynoText: TextField;
In your Constructor or else where at a soon level, give to your vars the proper value:
inputText = getChildByName('locationinput') as TextField;
dynoText = FlashingWon.Won1.getChildByName('name') as TextField;
This way you will soon enough know if one of this 2 textFields were not found under the object you give, and you have only one place to miss spell it. Also you will get code completion on your TextFields.
Finally the copy text part:
dynoText.text = inputText.text;
Hope it helps.
Alright, sorry for the delay, I was out on holidays.
I have opened your example and can see where the problems are:
1) You are trying to reach the FlashingWon when initiating the dynoText on the FIRST frame like so var dynoText = FlashingWon.Won1.getChildByName('name_txt'); BUT the FlashingWon element is ONLY available on the FIFTH frame. Meaning that you cannot refer to it quite yet, unless you add it on the first frame and make in invisible till the fifth frame. (You can make it visible in the goto1 function if you wish after the goToAndStop(5) line)
2) You called the TextField on the Won1 element 'name' which is a restricted sting in AS3, so change it to name_txt or label if you wish and it will work.
Let me know how it worked.
well i created some variables in the main stage level, with something like this:
for(i=0,i<10,i++){
var var_name="var_num_"+i;
this[var_name]="some value";
}//<-----------------------------------------------------works
so i get 10 variables named "var_num0", "var_num1", "var_num2" each one with some value.
and i can acces them any where calling this
var second_var=MovieClip(root).var_num0;//<--------------works
my problem comes when i want to call all the variables from a lower level or in another frame or somewhere else using another loop:
var third_var;
for(j=0,j<3,j++){
third_var=this["MovieClip(root).var_num_"+j];//<---------DOSNT WORK
trace(this["MovieClip(root).var_num_"+j]);//<------------returns "undefined"
}
how can i make this work? i tried a lot of things and nothing...
thanks you all
In your case both "root" and "this" are the scope you want to access the vars from. so try this:
var third_var:MovieClip;
for(j = 0; j < 3; j++)
{
third_var = MovieClip(root)[var_num_ + j];
trace(third_var);
}
Also you should have semi-colons in your for loop rather than comers.
I'd like to preface my answer with a suggestion you use a 'Document Class' with AS3 to make things like namespaces and inheritance much clearer. You know exactly where things are accessible when using document based, object oriented programming versus the timeline programming available through the Flash IDE (its only there because of AS1/2). Tut: http://www.kirupa.com/forum/showthread.php?223798-ActionScript-3-Tip-of-the-Day/page14
On to the answer: You are trying to move two levels of inheritance in one set of [] Another way of writing your first "Doesn't work" line is:
this.myMovieClip["var_num"+j"];
You could also use: this["MovieClip"]["var_num"+j];
Basically, you need to take the "MovieClip(root)" out of the string you are using to call your variable because you are passing through two levels of inheritance: this->MovieClip->targetVar
You need to use two periods, a period and a set square bracket or two sets square brackets to move two levels of inheritance. A period . and a set of square brackets [] both accomplish the task of moving one level deeper, so putting the . inside the string used to call up your variable won't work.
Explanation:
The following three examples all return the same variable:
myMovieClip.my_variable
myMovieClip["my_variable"]
var str:String = "my_variable";
myMovieClip[str];
I am looking for some advice on the best way to read in like 200k words and have them each tween from the center of the screen as small dots and tween up to the word filling the SWF then "fly through my head" not literally, but you probably get it...
What would be the best way in AS3 to go about this? I am fairly new to it.
Thanks!
Depending on the origin of your text, you may have to use regular expressions to get rid of punctuation and replace any amount of spaces by a set delimiter.
You could then use the split method of the String class to turn your text into an Array of words.
Each word can then be assigned to a Textfield. Since the Textfield is a DisplayObject, all the manipulations you are mentioning above become possible.
You may be able to streamline all this by creating a class that extends Textfield and defining various methods for the motions you want to implement.
You'll probably want to look at the Timer class and some tweening libraries
Pseudo Code
- Clean up String with regular expressions
-> expected result var cleanString:String = "word1;word2;...wordn";
- Turn String into Array
var words:Array = cleanString.split( ";" );
- Create a class that extends Textfield and define a manipulate() method
var tf:MyTextField = new MyTextField();
//this method could take parameters
//such as x, y, scale , time , delay , ease etc...
tf.manipulate();
- Create an Array( Vector ) of Textfields
loop thru words Array to return array of Textfields
var objects:Array = [ tf1, tf2 , etc...]
- Manipulate objects
loop thru objects Array to manipulate them
if you don't want to do it by hand (like PatrickS described) maybe this will help you ...
http://www.greensock.com/splittextfield/