I have a problem with using a variable that I declared outside the class, in a class. If I try this, Unity acts as if the variable doesn't exist.
#pragma strict
var chunkWidth=49;
class Chunk{
var width:short;
var position:Vector3;
function Chunk(pos:Vector3){
this.width=chunkWidth; //this gives the error: Unknown identifier: 'chunkWidth'.
this.position=pos;
}
}
This error also occurs when I want to use a function within the class.
You can change a variable in the inspector view if the variable is made public. Put the variable inside the class and make it a public variable. Then go to Unity and click the object that has this component attached. You can then change the variable in before you hit play. The variable will save in unity, but not in your code. So if you use this code with another object the variable will need to be set again in the inspector. But once set Unity will save that value within your project.
Related
I'm new in AS3 and I wanna ask how to access variables inside MovieClips by its name.
in AS2 usually, I use its instance name followed by .(name of variable)
for example...
I have a variable named baru inside a MovieClip named my_mc.
usually I use my_mc.baru to reveal the value of the variable.
Now, i want to know how to do it in AS3
Thank you.
In AS3 there's a few separate but related things you need to be aware of:
All display objects (including MovieClip) can have a name property.
var mc:MovieClip = new MovieClip();
mc.name = "myMC";
myContainer.addChild(mc);
You can find a child by its name using getChildByName() on its parent.
var myMC:MovieClip = myContainer.getChildByName("myMC");
MoveClip instances can have dynamic properties that point to children (or anything at all).
myContainer.myMC = myMC;
(Note that other display object types, such as Sprite, do not allow dynamic properties. Instead you need to create a custom class with class properties.)
When you create a display object in code (as shown above), neither the name or a property on the parent will be automatically created. You can do it manually as shown above.
When you place a symbol instance in the authoring tool and give it an "instance name", both the name and a property on the parent symbol will be assigned by that "instance name". In this case you are not allowed to change the name in code.
Note that in AS2 using createEmptyMovieClip or attachMovie would assign the _name and create a property on the parent, but there's no AS3 equivalent to these functions. This is where a lot of confusion can come in.
So as you can see the way this works is really not different than AS2, except that AS2 had functions that did several things for you (create and add the MovieClip, set the name and add a property on the parent). The problem with AS2 was that you couldn't re-parent an object after it was created, which was a big limitation. In AS3 you can freely move things around.
If you just like to write code inside the MovieClip but not a *.as,you have to add a TextField in the MovieClip by hand,set it's type to Dynamic,then type the variable string in it,then get it use: MovieClip.TextField.text and don't forget: TextField.alpha=0.
It is not a wise way.
What I want to do is to add button as a child to a movie clip which is on stage. Get input in a text field and then save that input into String variable. This button should trigger this actions. Only problem I find is that I can't reach the button which is in library. I have set button AS linkage and I am trying to reach it trough that linkage.
This is the line of code which dosen't work:
enterName.addChild(nextButton);
Error I get is: Line 254 1061: Call to a possibly undefined method addChild through a reference with static type Class.
Since your button has a linkage, you should instantiate it, which means:
enterName.addChild(new nextButton());
An even cleaner version would be to have your linkage name with a first letter upper case (this is commonly how classes are named). And you could cast this instance as a DisplayObject to tell the compiler you know this class extends something you can add to a container:
enterName.addChild(new NextButton() as DisplayObject);
I've worked around this with a hack for now, but would rather know if there's a right way to do it. I have a function that churns out MovieClips, which are tiles for a map that I then attach to the stage. It determines which class of tile to use based on a string variable, like this:
// symbolID holds our class name, determined by logic above
var newClass:Class = getDefinitionByName(symbolID) as Class;
var newtile:MovieClip = new newClass();
This works, but only if an instance of the class already exists somewhere else in the code. It could be anywhere-- in the document class, in some buried function of a helper class, it doesn't seem to matter. If not, Flashdevelop throws error 1065, "Variable (the variable) is not defined". I mention that I'm using Flashdevelop because it seems like it might be compiler-specific, but I'm not sure.
My hack fix is to do this:
var a:baseTile;
a as anotherTile;
a as aThirdTile;
and so on, which works, but definitely isn't ideal if I'm going to have hundreds of these tile classes eventually.
Edit: I should add that these movieclips are coming from a .swc file, which comes from Flash Professional.
You have to use the 'hack'.
getDefinitionByName() can only work with classes that exist at runtime. Unfortunately, if you don't make use of a class, it won't be compiled and won't exist at runtime.
Library symbols make getting around this a little easier. If you check the box that has them available automatically at a given frame, you can just make sure your getDefinitionByName() calls are done during or after that frame.
While SWC libraries can include specific classes to include in the build path, Flash compiler will not link unreferenced classes to a SWF; therefore, requires a linkage library.
Example linkage to retain classes:
/** linkage library */
private static const classA:ClassA;
private static const classB:ClassB;
private static const classC:ClassC;
Another option would be to load the classes from a RSL (Runtime Shared Library).
Basically yes, you need to have a strict reference of that class somewhere in your code. You can even make that reference "unreferenced" elsewhere. I have a hundred of classes like this, and I had to make a single Array of these classes, located somewhere inside the project. I have placed it aside the function that calls getDefinitionByName() to make sure the classes are available in that function.
private static const dummy:Array=[Rock01, Rock02,...,Gem01,Gem02,...];
So you can use such an Array listing all your tiles that you have in your project and want to be accessible by getDefinitionByName().
So im quite new to AS3 but have worked with AS2 a lot before.
I have created a button and placed it on my stage then inside my class i have added this:
test.addEventListener(MouseEvent.CLICK, buttonClicked);
function buttonClicked(ev:MouseEvent):void
{
trace("Clicked");
}
Now this does not work as it can't find the stage, the only way i can get this to work is if i put the listener on the same frame as the button & not in the class.
But there must be away around this.
Thank you.
Eli
Update - adding Error messages
If I keep the above code all in the external class these are the errors i get.
Line 22 1120: Access of undefined property test. Line 22 1120: Access
of undefined property myButtonClick.
If you have created a document class with timeline then your "test" button must be in first frame. Because document class starts executing from first frame. You can access your button instance only when its available in stage.
Oh, I forgot to mention. You have to declare those instances as public variable in your document class.
public var test:SimpleButton;
Please go thru below and let me know which of the way you were having.
1) Are you having Document class?
There is a field Class in the Document Properties under the Publish tab of the flash IDE, if you are giving your class name in that field then it is called as Document Class
If you are having document class then you can create listener to your button even in the constructor button. Flash won't throw any errors like you got.
2) If you are instantiated your class in the first frame, it won't have the properties of stage till you add that to the stage using addChild. Also it won't have access to your button. And so it will throw the error, The access of undefined property.
Have you assigned the instance of the button on the stage the name "test"? The error message you posted seems to say there is nothing with the name "test" to assign the event listener to.
To check, click on the button the stage and look at the 'Properties' tab: will show in a text box near the top if it needs assigning.
Now the second error you posted means you're referring to something called "myButtonClick" without first declaring/initialising a variable/function with that name. You will either need to declare it or correct it if you meant to refer to something else.
Fixed.
I was being rava stupid as normal, forgot to put them inside the init :|
For the people who might come across this problem.
Working Code:
public function Main()
{
// constructor code
test.addEventListener(MouseEvent.CLICK, myButtonClick);
}
function myButtonClick(ev:MouseEvent):void
{
trace("button Clicked);
}
Anyway thanks guys for the help sometimes its just the simplest answers are the correct ones.
Eli
In document class, constructor, following line produces following error:
name = "hello world";
Error: Error #2078: The name property of a Timeline-placed object cannot be modified.
Is this doable or hackable?
I did some test, and it seems you can't.
"MainTimeline is the default class used for the document class. The document class is the display object which is added to the stage when the SWF movie is loaded. Underneath it is a normal class which extends MovieClip." (found here on SO)
Probably the implementation of this class blocks you to change its name. As you're not instantiating it, probably flash assign a name to this instance and doesn't want you to change it :)