I really wonder. I made a MovieClip class Apple, I wrote a function that creates a new instance with a name "apple". Each time a new instance is pushed into an Array "apples". I call the function 5 times and I get 5 apples. I can manipulate them by calling them i.e. apples[0]. And when I trace my array I see 5 [object Apple] things. So maybe I don't really understand the structure of AS3 objects but shouldn't each object have a name?
When I set apple.name and get an array with 5 different names, I can't manipulate objects by names like apple1.x = 10. How does computer know which apple is where if each has own coordinates? Is the only way to call them: apples[0]-apples[4]? And if I create a code that should be same for all apples, how should I address the function, to "this"? Cause when I write class code I don't have any names yet...
For example, if I want to make Apple class a picture(MovieClip) that can be dragged, create any number of apples, up to a million, I can't possibly add apples[0].addEventListener, apples[1].addEventListener ... apples[1000000].addEventListener to the code. How do I make it global?
I'm asking cause when I'm directly coding for a specific instance, it has a name and I know exactly what am I addressing. And working with a class and making many objects I kinda don't... Sorry, I'm green
You don't need names to be able to access and manipulate your instances.
You can do something like this:
var apples:Array = new Array();
for (var i:int = 0; i < 100; i++)
{
var apple:Apple = new Apple();
apples.push(apple);
apple.x = Math.random() * 500;
apple.y = Math.random() * 500;
addChild(apple);
apple.addEventListener(MouseEvent.CLICK, onAppleClick);
}
function onAppleClick(e:MouseEvent):void
{
var ind:int = apples.indexOf(e.currentTarget);
var apple:Apple = apples[ind];
trace(ind);
apples[ind].visible = false;
//or
//apple.visible = false;
}
The same problem, huh? :)
For example Apple extends Sprite and inherits property name.
It's public, this means that you can change its name.
var apple:Apple = new Apple() ;
apple.name = "MegaApple" ;
Also, if you add the apple to stage, you can get him via name.
stage.addChild(apple) ;
get apple back:
var oldApple:Apple = stage.getChildByName("MegaApple") ;
But that never means, that you can use apple like that:
MegaApple.move() - because name of apple is supposed to be a property of apple, not a name of a variable.
Of course, you can create a lot of apples manually:
var apple1 = new Apple() ;
var apple2 = new Apple() ;
var apple3 = new Apple() ;
But if they all behave the same way, there is no point in doing. That's why you store them into array.
Hope you understand what I mean.
Related
I've spent nearly 1 week to learn working with objects instead of arrays. I had thought it was easy to call them and created some objects and set their properties. However I can't access them now, I tried this:
function onBoxClick(event:MouseEvent):void {
var str:String = event.currentTarget.name;
trace(str);
str = str.substring(str.indexOf("_") + 1);
trace(getChildByName("copy_" + str)); // trying to trace an object by name
}
My question is if there's a practical way of dealing with objects, otherwise what's the purpose of using them.
Edit: Here's my function that I use to create movieclips and other things:
function addBoxes(isUpdate:Boolean):void {
var copyOne:Object = getReadOnlyValues();
copyOne.name = "copy_" + num;
// Set default mc1 settings
var settings1:Object = copyOne.mc1Settings;
for(var num2:String in settings1) {
copyOne.mc1[num2] = settings1[num2];
}
// Set default mc1text settings
var settings2:Object = copyOne.mc1TextSettings;
for(var num3:String in settings2) {
copyOne.mc1Text[num3] = settings2[num3];
}
copyOne.mc1.x = nextXpos;
copyOne.mc1.name = "captionBox_" + num;
addChild(copyOne.mc1);
copyOne.mc1.addEventListener(MouseEvent.CLICK, onCaptionClick);
copyOne.mc1Text.name = "captionBoxText_" + num;
copyOne.mc1.addChild(copyOne.mc1Text);
// ---------------------------------------------------------------
// Set default mc2 settings
var settings4:Object = copyOne.mc2Settings;
for(var num4:String in settings4) {
copyOne.mc2[num4] = settings4[num4];
}
// Set default mc2text settings
var settings5:Object = copyOne.mc2TextSettings;
for(var num5:String in settings5) {
copyOne.mc2Text[num5] = settings5[num5];
}
copyOne.mc2.x = nextXpos;
copyOne.mc2.y = copyOne.mc1.height;
copyOne.mc2.name = "box2_" + num;
addChild(copyOne.mc2);
copyOne.mc2Text.name = "box2BoxText_" + num;
copyOne.mc2.addChild(copyOne.mc2Text);
copyOne.mc2.addEventListener(MouseEvent.CLICK, onBoxClick);
if (num / subunits is int) {
trace (num);
// createMc("normalBox", true);
}
nextXpos = nextXpos + copyOne.mc2.width;
// traceObj(copyOne);
// traceObj(getReadOnlyValues());
}
I called this function in a loop so I created many movieclips. Now I can't access objects' properties and their childen (e.g textfield).
Objects I have on stage: Movieclips and textfields
Where they come from: The function above
What I'm trying to do with them: Tracing movieclips and textfields (that are holded by objects) to change their children (textfield) text
What happens instead of what I expect: Trace code outputs undefined instead of giving me object type trace(getChildByName("copy_" + str)); // trying to trace an object by name
Is there a practical way of accessing an object whose name is "copy_1" and its property whose name is "box2_1" (movieclip)?
One problem I see is the "copyOne" object has been created within the scope of "addBoxes", so it will no longer exist outside of this function.
Another is you're trying to access an Object via getChildByName, which only addresses displayObjects of the displayObjectContainer you are calling from.
If you want to loosely keep track of variables with things like Objects or MovieClips (which are both dynamic-style objects that let you add properties to them as you wish), just use MovieClips to house your values. The movieClips, being on the stage, will be retained in memory until removed from the displayList (stage).
Also, check out the Dictionary, a sort of key/value based way of storing collections of objects.
Better yet, if you use strongly-typed custom objects (creating your own classes to extend MCs, and adding your own public or private methods and values), there are benefits such as using Vectors (fancy, fast arrays that are compatible with any Object type you choose).
I don't really know if I understood your question or not, but as #ozmachine said in his answer, you can not use getChildByName, instead I think that you can take a look on this, may be it can help :
var container:DisplayObjectContainer = this;
function getReadOnlyValues():Object {
return {
mc1: new box(),
mc1: {
name: 'mc1_',
alpha: 1,
x: 0,
y: 0,
width: 30,
height: 25
},
mc1Text: new TextField(),
mc1Text: {
text: 'test',
x: 0,
y: 0,
selectable: false,
multiline: false,
wordWrap: false
}
}
};
// create 5 objects
for(var i=0; i<5; i++){
container['copy_'+i] = getReadOnlyValues();
var obj:Object = getObjectByName('copy_'+i);
obj.mc1.alpha = 1;
obj.mc1.x = 0;
obj.mc1.y = 50 * i;
obj.mc1.width = 100;
obj.mc1.addChild(obj.mc1Text);
obj.mc1Text.text = 'test_' + i;
addChild(obj.mc1);
}
// get object by name
function getObjectByName(name:String):Object {
return container[name];
}
// change the text of the 4th button
stage.addEventListener(MouseEvent.CLICK, function(e:MouseEvent):void {
var obj:Object = getObjectByName('copy_3');
obj.mc1Text.text = 'new text';
})
Array and Object are both data structures.
Data means some form of information.
Data structure means some form of information being stored in a certain way.
Array and Object are two different ways to store information.
Arrays identify data with integer numbers.
An integer number to identify a single element of an array is called an index
Arrays are ideal to represent a list of similar things that belong to each other.
var names:Array = ["John", "Paul", "George", "Ringo"];
This often means that the elements of an array are of the same type, like in the example above.
But they don't have to:
var numbers:Array = [42, "twenty-five", "XIIV"];
For the above examples it's easy to answer the questions "What are the names of the four beatles?", "What different representations of numbers did you stumble upon during your trip through the historic town?". Other questions are harder or impossible to answer. "What Roman numerals did you stumble upon in the historic town?"
Objects identify data with names.
A name to identify a single element of an object is called a property
Objects are ideal to represent a list of dissimilar things that belong to each other.
var paula:Object = {age:37, name:"Paula", hairColor:0x123456};
This often means that the elements of an object are of different type, like in the example above.
But they don't have to:
var car:Object = {manufacturer:"Porsche", color:"red", sound:"wroooooom", soundOfDriver:"weeeeeeeeeeee"};
Considering this, let's take a look at your code and see how it applies.
The big picture is that you have a function addBoxes that you call multiple times. As one function should have one purpose, this function will do something similar every time it is executed. Uh-Oh: "similar". Whatever the result of this function is, it should go into an array. Each call to that function would be an element of the array. You can see this clearly on your use of "num" to identify whatever is happening in your current run of the function.
What data is present in your function?
copyOne
mc1
mc1Text
mc2
mc2Text
copyOne is a troublemaker here and what causes your confusion. It's trying to do everything at once and therefore you are not able to think clearly about when to use a Array and when Object. One would call it a god object. And that's not a good object to have around.
Your choice for variable names is very bad.
You choose super generic names like "mcX" only to later add a name property to it that describes what it truly is.
But even that doesn't hold true for whatever "Box2" is supposed to be.
Choose names so that it'S easy to understand what something in your code is.
It looks like you created all or parts of this structure jsut for this question and therefore lacked meaningful names.
I highly recommend that you do not learn by such made up projects. But from the real world.
I will therefore impose the following goal:
mc1 and mc1Text represent a caption
mc2 and mc2Text represent a content
With all this, I ask again:
What data is present in your function?
captionBox
captionText
contentBox
contentText
Both caption and content consist of a box and a text.
These are different things, so caption and content are each an object with properties "box" and "text"
One could think that due to this similarity, they both should go into an array.
But I beg to differ. A caption and a text are not the same thing. You deal with captions and texts differently. Walking on the streets you might catch a big caption in the news quickly, but not a lengthy text. That's why each of them should be a property of the object that's created in the function.
Here's somewhat of a conclusion:
var allBoxes:Array = []; // array to store the similar results of every function call
function createBoxes():void
{
var boxes:Object = {};
//the box consists of caption & content, both bying of the same type, but are containing different data
boxes.caption = {box:{}, text:{}}; //caption
boxes.content = {box:{}, text:{}}; //content
allBoxes.push(boxes);
}
This is it. That's how and why I would model your data with objects and arrays.
But it doesn't end here. My conclusion lacks a lot of the code you posted.
While the above is mostly language independent, the missing code is specific to Actionscript and not just on how to model data. It's as follows...
As3 is object oriented.
This is good, because the above conclusion has a lot of objects in it.
To define how some object is/does/moves/farts/etc, one creates classes.
The following changes take place (for reasons out of the scope of this answer):
createBoxes (formerly known as addBoxes) calls the constructor of
a class "CaptionAndContent" that extends Sprite.
There's no more need to explicitely create an object "boxes" as the constructor does exactly that.
The caption and content will not have a property "box", because
they can be the box themselves. This is exactly how it's done in the
code of the question. The default settings are set in the constructors of their classes.
Here's reduced snippet of code that hopefully illustrates how the classes could look like.
Each class should be in its own file, with the necessary imports, package block and the additional functionality that you did not specify in your question.
public class CaptionAndContent extends Sprite
{
private var caption:Caption;
private var content:Content;
public function CaptionAndContent(captionText:String = "", contentText:String = "")
{
caption = new Caption(captionText);
addChild(caption);
content = new Content(contentText);
content.y = caption.height;
addChild(content);
}
}
public class ClickableBoxWithText extends Sprite
{
protected var textField:TextField;
public function ClickableBoxWithText(text:String = "")
{
textField = new TextField();
textField.text = text;
addChild(textField);
addEventListener(MouseEvent.CLICK, onClick);
}
protected function onClick(mouseEvent:MouseEvent):void
{
//override this in a sublclass
}
}
public class Caption extends ClickableBoxWithText
{
public function Caption(text:String = "")
{
super(text);
// apply all the default settings of caption here.
}
}
public class Content extends ClickableBoxWithText
{
public function Content(text:String = "")
{
super(text);
// apply all the default settings of content here.
}
}
Using them would look something like this:
var allBoxes:Array = []; // array to store the similar results of every function call
function createBoxes():void
{
var captionAndContent:CaptionAndContent = new CaptionAndContent("This is the caption...", "...for this content");
captionAndContent.x = nextXpos;
addChild(captionAndContent);
allBoxes.push(captionAndContent);
}
Last but not least, the identification problem in the click handler.
Your question already contains the answer:
event.currentTarget
That's the reference to the object that was clicked on.
In my code it would be
mouseEvent.currentTarget
This identifies the object already. It's pointless to look up one of its properties (its name for example) in order to search all the objects for that name, just to identify the same object that you already had to identify (without a name) in order to get the name.
You aren't identifying the objects by name anyway. What differs between the names and what supposedly makes them unique is a number at their end. As pointed out in this answer, this is what's called an index and the thing you are trying to identify with it should go into an array. In my example codes, this is allBoxes.
Im really stuck. I have 5 MC´s that are being spliced from one array at a certain time. In that same function I want to push another movieclips into another array. The two arrays holds mc's that represent right or wrong answers. So when one question is being given a correct answer that questions visualisation alters.
This function holds a incrementing variable as I do want the mc's to be pushed by the user and one at the time. The thing is I cant seem to refer them properly.
I´ve tried
pQuestSum = this[pQuest + pQuestNumber];
and
pQuestSum = this[pQuest] + pQuestNumber;
and pretty much everything I´ve imagined would work...but the problem is I havent tried
the right thing.
when I trace pQuestSum (which would be the reference) I get an error saying thats its not a number.
this is one of 5 mc's named from 1-5:
var passedquest1:PassedQuest = new PassedQuest();
this is the vars that i try to to build a reference of
var pQuest = "passedquest";
var pQuestNumber = 1;
var pQuestSum;
var questCorrArray:Array = [];
if(event.target.hitTestObject(questArray[ix])){
removeChild(questArray[ix]);
questArray.splice(ix,1);
pQuestNumber ++;
pQuestSum = this[pQuest] + pQuestNumber;
trace("pQuestSum"); // NaN
questCorrArray.push(pQuestSum);
//trace(questArray.length);
pointsIncreased = false;
questPoints = 0;
}
How do I refer an existing movieclip when the reference consists of both a string and a number? Hope I made myself somewhat clear:)
If you had an instance of an object on your timeline called "passedquest1" (as an example), then you could access it this way:
var myObj = this["passedquest" + 1];
Or,
var pQuest = "passedquest";
var pQuestNumber = 1;
var myObj = this[pQuest+ pQuestNumber.toString()];
When you do this: pQuestSum = this[pQuest] + pQuestNumber;, you are trying add the number to an object (this[pQuest]), unless you have number/int var called "passedquest", this will result in NaN.
I made an invetory in AS3 which allows me to put items on slots in a closet, or in slots in the inventory. It completely works, but there is one problem.
In the game you are supposed to be able to buy new items and add them to the closet. I want this to be saved so that it is available the next time you play.
To do this, I want to save an Array to a SharedObject, then create the items dynamically from the array.
Right now I'm using the old fashioned hard coding for each object;
Itemwrench = new WrenchItem();
Itemwrench.x = par.toolCloset.kast_1.slotTC1.x + 400;
Itemwrench.y = par.toolCloset.kast_1.slotTC1.y + 245;
Itemwrench.gotoAndStop(2);
Itemwrench.name = "slotTC1";
Itemwrench.TC = 1;
NotinventoryParentTC.addChild(Itemwrench);
However, to add them dynamically I'd have to use getChildByName before it is added to the stage, which is not possible.
If possible could you show me how to do this correctly?
The information you need:
-The items are all stored in a closet with slots(Instances in the closet movieclip).
-The items need to get the name slotTC + the integer in a for loop.
-The name of the items change according to the slot number they are assigned when you take them out of the closet or put them back into the closet.
for(var i:int = 0; i < itemsInTC.length - itemsInTC.indexOf(e.currentTarget.name) - 1; i++)
{
nextSlotTC = "slotTC" + (itemsInTC.indexOf(e.currentTarget.name) +2 +i);
trace("Next Slot: " + nextSlotTC);
TempStrTC = "slotTC" + (itemsInTC.indexOf(e.currentTarget.name) +1 +i).toString();
trace("temp string: " + TempStrTC);
NotinventoryParentTC.getChildByName(nextSlotTC).x =
par.toolCloset.kast_1.getChildByName(TempStrTC).x + 400;
NotinventoryParentTC.getChildByName(nextSlotTC).y =
par.toolCloset.kast_1.getChildByName(TempStrTC).y + 245;
if(Boolean(NotinventoryParentTC.getChildByName(nextSlotTC)))
{
NotinventoryParentTC.getChildByName(nextSlotTC).name = TempStrTC;
}
}
This way I assign a new name and place them in the slot with the new name they received.
So now my question:
How do make it so that you can save the items to a shared object so that they are in the closet the next time you play the game.
Sorry for the long question.
Thanks in advance,
Milan.
You cannot directly store a DisplayObject in a SharedObject, as it contains memory links which will not be valid if you load such an object. A comon way to work around this is to store a significant data portion of that object. For example, you devise a following structure:
class SlotStructure {
public var slotID:int;
public var itemID:int;
public var itemName:String;
public var itemParameters:Array; // stuff simple types here
}
Then, for each of your items in inventory, you generate a SlotStructure object describing a particular inventory object. For your wrench it could look like this:
var ss:SlotStructure=new SlotStructure();
ss.slotID=1;
ss.itemID=getID(item); // assuming a function that returns a type of an item
ss.itemName=item.name;
ss.itemParameters=new Array();
for (var param:String in item) ss.itemParameters.push({name:param,value:item[param]});
Then you store an array of these into your SharedObject. To retrieve an inventory from a SharedObject you do:
public static const
registerClassAlias("SlotStructure",SlotStructure); // to be able to typecast from SO
for (var i:int=0;i<slots.length;i++) {
var ss:SlotStructure=slots[i];
var item:Item=new getClassFromID(ss.itemID)(); // a function that returns class
// say 1 - wrench, 2 - short sword, 3 - long sword, etc, one type=one ID
for each (var o:Object in ss.itemParameters)
item[o.name]=o.value;
placeIntoSlot(item,ss.slotID); // this does manipulation with x&y and display
}
A function getClassByID() might look like this:
private static const CLASSES:Array=
[StoneItem,WrenchItem,ShortswordItem,LongswordItem,...];
// manually stuff all your items in this!
public function getClassByID(id:int):Class {
return CLASSES[id];
}
The entire solution can be tailored to particular task, for example, in my game I have gems, that differ by location, type, size and score, so I store just these values and then I create new gems, set location, type, size and score with one function that sets all the other relevant parameters of that gem to align with stored info, and call it after making a gem with new Gem(). Your items might too be only worthy of a class name and ID in the class table, so store these with slot numbers and create objects that will have all their properties already set.
I need to have the screenPage var accessible for later calls. I am dynamically creating several pages. The issue is when I call screenPage.startDrag(); then it only drags the last page. How can I add a var in the name or make all the screenPages accessible through code?
Here is code in short:
var screenPage:MovieClip;
for(var p = 1; daTotalPages >= p; p++)
{
screenPage = new theFlagScreen();
}
Can I make screenPage a dynamic var and add like a 1 at the end and then a 2 and so forth with the loop?
Why not use an array ?
var pages:Array = new Array;
for(var p = 1; daTotalPages >= p; p++)
{
var screenPage:MovieClip = new theFlagScreen();
pages.push(screenPage)
}
Now you have an array containing all of your instances.
var myPage:MovieClip = pages[5] as MovieClip;
myPage.startDrag();
Also, the code you have above is creating an instance each time through, but since you then go ahead and create a new one each iteration and assign it to the same variable without storing it or adding it to the display list.... once you create a new one, the last one is marked for garbage collection.
The result is only the LAST instance you created still exists as it's the only one that has a variable that references it.
screenPage is a reference to just ONE thing. In your loop you keep overwriting it as you go and so you end up with it pointing to the very last instance of theFlagScreen... all the others are now lost.
You should follow prototypical's advice and store these instances in an array, that way you don't lose them.
I have a collection of movieclips, I would like to create a clone (a new instance) of a instance everytime I create a new object.
For example
var s:Star = new Star(); // star-shaped movielcip
addChild(s);
// then I want to duplicate an instance of s and add it beside s
For an example like above, it's simple enough to create a new instance with a different name and just add it to the display list. But I have a list of objects I would like to clone as a group...?
Belowed code is very famous for cloning the objects. It's deepest and dynamic.
...
function clone(orjObj:Object):Object {
var copyObj:ByteArray = new ByteArray();
copyObj.writeObject(orjObj);
copyObj.position = 0;
return(copyObj.readObject());
}
var s2:Star = clone(s);
s2.x = s.x + s.width;
s2.y = s.y;
addChild(s2);
moses' solution is correct. What is the purpose of the clone, where you wouldn't need to know the name of the clone to reference it?
One option is you could create an array to store your references in so you don't need to explicitly name them. Using moses' code...
var clones:Array = new Array();
for each (var star:Star in [s, s2, s3, s4, s5]) {
clones.push(clone(star));
}
trace(clones.length); // 5
This will result in an array that holds 5 cloned stars. It takes the least amount of code but it's up to you to make sure you know which star is which afterwards.