ActionScript 2.0 :: Use Local Instance Variables Vs Attach New Properties To The Instance Object?
Mar 14, 2006
I am wrapping my brain around OOP in AS2. I am making two posts on two different subjects. My question here is: when should I use local instance variables, and when should I attach new properties to the instance object? (Feel free to correct my terminology.) Let's say I have a class for a scrolling background, which scrolls when I mouse over its edge. I want to put these values somewhere:
1) How wide is the border in which a mouseOver makes it scroll? This is basically a semi-constant I set it up once and keep it the same, unless the user changes it in an options menu to make the border wider or narrower. Call this scrollBorderWidth.
2) How fast is the background scrolling now? I want to track this so I can smoothly change the scroll speed over several frames. This is often changed. Call this scrollSpeed.
It seems I have two ways I can store and access these values and darned if I know which is better practice. METHOD A: Make them local variables in the class, so the scrolling background instance has them as local vars. I set them up thusly:
Does creating a new instance of an Object that uses an identical name to an older instance, delete the previous instance? Or should the original instance be deleted first? The code uses a ridiculous amount of XML vars. Isn't it less memory intensive to parse the XML and save the properties to an Object, and then delete the XML Object, rather than keep the XML Object around and reference it's child nodes directly? Is it better form to break up a huge XML file (>600lines/3200vars) into smaller chunks?
I am programming a web based application with Actionscript 2.0 classes for flash 8, and I want to save user data using the local shared object.As the data is potentially rather complex I would prefer to store it in an instance of a custom class that I then stick in an array property of the local shared object data property.However, when I try to do this, if I retrieve the stored object it seems to have lost all its instance methods. If I do a for in on it, I can see the private properties to which I have assigned my data, but as they are private I cannot retrieve them.how I can store an instance of a custom class in a local shared object without it being corrupted in this way?
I am using this code to iterate through the contents of a movieclip which contains instances of "alien2" - my alien. I have each alien in a movieclip called squadron1. They all have their own layer and follow a motion path to recreate the attack sequence in Galaga. I can add action script to them by right clicking on them, but when I do this test below I can't call any MovieClip methods on them. It is my intention to add a function to each one via code to make it detect bullets, look for the player etc, but at the moment all I can do is add the code to each one individually on the stage.
Code: var target; for(var item in _root){ if(_root[item] instanceof MovieClip ){ target = _root[item]; [Code] .....
I'm having a little trouble with the properties of an instance of a specific class. Here's and example of the code I am using:
Code: package { import flash.display.MovieClip; import flash.events.*; public dynamic class Circle1 extends MovieClip { private var _root:Object; [Code] .....
This is in the class code for Circle1. Now here is the error that is being displayed int he Output Box when I try to run the file: Code: TypeError: Error #1010: A term is undefined and has no properties. at Circle1/eFrame()
Here's the code that creates the two class instances as children on the Main Time Line: Code: if (spaceDown) { var newCircle1:Circle1=new Circle1(); addChild(newCircle1); } if (enterDown) { var newCircle2:Circle2=new Circle2(); addChild(newCircle2); } EnterDown is a defined variable for the key press of Enter, and spaceDown is a defined variable for the key press of Space.
Through searching the various forums I have found that Loaders are not dynamic and hence you can not apply custom properties to each instance of them. I miss the old way (as2 way of attachingMovieClip) that you load dynamic content, at least you can apply custom properties, and you can always reference them for each object.What I'm trying to do is load a group of Images via XML. Each one of those images have a set of information that is associated with them (name, description, etc). I have the images loading in and positioning just fine, however when trying to have a tooltip show the name on Mouse Over, I'm not able to achieve this.
In short. I want to be able to store information for each item so that I can access it. Is there a way to do this in AS3 with a Loader or is there another route I can go? If I do this with Arrays, how do I store the Index of the specific item so I can use that in reference to the position in each array?** Should I use getChildIndex() in the function for the Event Listener to reference the data stored in the arrays for each item? If so, how do I do so? ***
PHP Code: num = 0;var titleArray:new Array();function createImage(){ var thumb:Loader = new Loader; thumb.load(new URLRequest(url);
I have a Matrix which I recycle and use for drawing DisplayObject instances onto a Bitmap. At the moment, I reset the Matrix before I render each item, like this: _matrix.a = 1; _matrix.b = 0; _matrix.c = 0; _matrix.d = 1; _matrix.tx = 0; _matrix.ty = 0;
Would it be better to do the above, or to simply do this?: _matrix = new Matrix(); Generally I would say the former, however I'm unsure if in the case of Matrix there is some heavy stuff going on for each of those properties that I reset (mathematically).
I have a library object (SomethingMC) which extends a custom class (Something). Something, in turn, extends MovieClip.If adding SomethingMC to the stage within Flash CS3 IDE, is it possible for it's super class (Something) to assign an instance name from a class constant (Something.THE_CONSTANT)?
The above does not work. It throws Error #2078: The name property of a Timeline-placed object cannot be modified. if the instance is assigned a name in the IDE, and it just doesn't work if no name is assigned in the IDE.
I have a BUNCH of bumpers of four types bounceUp, bounceDown, bounceLeft, bounceRight. during a collision which you hit determines the bounce so they always do the same thing so here's my question.....can i just name every bounceUp instance the same thing and then just add that one instance name to the list the collision detector checks?
i just dont wanna go through and name a hundred each of bounceUp s and bounceDown s individually as the potential for screaming increases proportionally.......
I placed a movie clip instance inside a button, and I want this movie clip to play when the button is released. I'm using this code on the frame containing the button:
function playMovie(event:MouseEvent) { this.theButton.theMC.gotoAndPlay(3);
Does anyone know if it is possinle to scroll a graphic or a movie instance as well as a text instance in flash. I want to scroll text and images as well. Actually text with imges embedded in it.
I'm using 9 textbox in my stage. Names are similar, only difference is the last character. (s1_0, s1_1, s1_2, ...). I'm trying to use these textbox in a loop. But I couldn't find the right typing... s1_[i], s1_(i) or s1_{i} gives error. s1_0.text=0 s1_1.text=0 s1_2.text=0 s1_3.text=0 s1_4.text=0 s1_5.text=0 s1_6.text=0 s1_7.text=0
It seems that my code is problematic, because I assign one instance of a MovieClip to several variables, type MovieClip. The behaviour of others of my codes makes me think, that ActionScript does not make copies of the instance, but references all variables to this single instance. This behaviour now causes trouble.The solution I consider now, is to create copies of the MovieClip and assign them to my variables. Is there any code to copy a MovieClip?
So in AS2.0 I would use _global.variableName to create and refer to a variable that was maybe created on the stage and then needed to be referenced to inside of an instance. That doesn't seem to work anymore. Are you expected to not want to do that, or is the code just changed now?
Im looking to have something along these lines, different variables that build the path to the object so that I can have it change dynamically.I'd like to have something like:
function foo(e:MouseEvent):void { var1.var2.var3+_button.gotoAndPlay(2); }
I've read on the net that actionscripting from the action layer will result in a more readable file once published, as apposed to attaching onClipEvent functions which slow down readability.
For this reason I am trying to add variables to a MovieClip I have on the stage with an Instance Name of Player. However I wish to assign the MovieClip variables from the actions layer using the MovieClips Instance Name.
I have created movie clips using loops that names them box1, box2, box3.... via = i + 1;duplicateMovieClip (_root.box, "box" + i, i);but i then want to edit a textbox which is rooted inside each movie but related to the movieclip just produced. so if box1 had just been produced then:box1.textbox.text = " E cell = +j+"V";is done so effectively i am looking to do: box+i.textbox.text = " E cell = "+j+"V";
I am using the tween class to change the alpha value of a MC upon rollOver and rollOut. To refine the effect, I assigned a variable to the MC's alpha value so if the mouse moves off the MC before it has reached 100% alpha, it wont start immediatly fading from 100%, but from the value it had reached before the user stopped the rollOver action. Unfortunately, when I leave my mouse over the MC until it goes to 100%, and then I wait a second or two, the alpha snaps back to 50% (the starting alpha value).I can't figure out why this keeps happening, but I have run into it with other projects and I surmise it is the way I am using the tween class. Below is the code I used to make this happen.To see the problem, here is a link to the compiled file:
In the following code I would like to be able to change which object the code affects depending on which parameter name is passed to it:
Code: EventCentral.getInstance().addEventListener(ProjectEvent.SOME_EVENT, handleSomeEvent); function handleSomeEvent($event:ProjectEvent):void
[Code].....
I could write it all out with ifs and else ifs for each parameter but this code is already part of quite a large structure and it would be more elegant to be able to do it with re-usable code.
I'm trying to do it is particularly idiomatic to actionscript anyway
I have two classes a main and one controlling a cloud graphic going on the stage. In the main class I am creating an instance of the cloud, adding it to the stage with an array and with a for loop I am setting the x speed (vx). I have noticed that if I set the vx in the cloud class and reference it directly then it does not work (clouds are drawn for a millisecond then a blank movie). I have to initialize the cloud.vx value in the main class to get it to work. Why can I not just pull the vx value from the cloud class without setting it to a value in the main class?
