ActionScript 3.0 :: Overriding The Width Getter On A DisplayObject
Dec 7, 2009
I frequently find myself wanting more granular control of the width/height properties. Consider either of the following cases:
- The DisplayObject is clipped with DisplayObject.mask, but Flash reports unmasked width.
- An image is displayed with a transform cage drawn over it. The width of the cage shouldn't be calculated when determining the DisplayObject's width.
The naive way to solve this problem is to override the width getter of the DisplayObject in question. The problem is that the core implementation of DisplayObject.width is written in native code. If after overriding the width getter, I call overridenObject.width, I get what I want; however, if I call overriddenObject.parent.width, DisplayObject.width ignores my override and calculates the dimensions based on its own internal display list representation.
Does anyone know of a technique to limit which children are considered when calculating width without having to override every parent's width getter? I've tried overriding width, getRect, getBounds, and scrollRect, but none of them seem to be referenced by DisplayObject.width's native implementation.
Is there a way to override the width (for a getter) on a Sprite?I see examples of how to override the setter but not the getterI need to do something like
override public function get width():Number { if (onecase) { return this width;
I have a collection of UIMovieClip components which reside in an s:HGroup tag. In ActionScript code I am modifying the width of a child clip in one of the UIMovieClips but these changes are not reflected by the s:HGroup.
Has anyone got any alternatives to what Colin Moock has coded to GET VISIBLE WIDTH/HEIGHT OF A DISPLAY OBJECT in ActionScript 3? That esp. in perspective of DisplayObjects that have 3D transforms applied and visible dimensions of which you need to consider for a calculation.
I would like to be able to quickly check if a given DisplayObject is a descendant (not in the inheritance sense - ie. child, grandchild, great-grandchild, great-great-grandchild, etc.) of another DisplayObject. There doesn't seem to be a native way to do this and I can only think of two ways to achieve it: Create the mother of all nested loops. Seems a bit, I dunno, wrong? Dispatch a bubbling event at the 'child' and check if the potential 'parent' receives it.
I have a setter and getter method , the getter method should return an array collection but it's always returning an empty array collection even when I've run trace to check on it.[code]...
I'm having trouble updating a property value of a custom class (SubLoader) using a getter and setter. Inside the if() statement of the main fla you can see my attempt to set the percent value. Running a trace() method before the if() statement always outputs '0' for some reason. Tracing after the if() statment outputs an actual value. I can't figure out why the percent property always traces as '0' before the if statement even though I am updating it with each progress event.
I'm finally reading up on commenting code with ASDoc (http:url]....) but the way ASDoc is set up doesn't seem to agree with the way I write my getter/setters.Here is how I write them:
Code: //I want to add the ASDoc tags here, before this chunk of code private var _enabled:Boolean = true; public function get enabled():Boolean[code]...
if I ad the tags where I want them, if I understand correctly, they will comment the private variable instead. Bummer.So, either I change the coding style I have been using for the past three years, or insert the tags inside of my code, making it ugly and less structured. I'm leaning towards option A.how do YOU write your getter/setters so they are ASDoc friendly?
I seem to have run into a situation where when I push a value to an array held within a singleton via a getter/setter , Flash seem so access the getter over the setter method. Within my command/controller (I am using RobotLegs)
override public function execute():void { // various line of code here //Place screenshot image into an array from model for later reference. model.unitScreenshots.push(screenShot); // screenshot is just a Bitmap object }
The getter and setter within my model e.g. robot legs singleton public function get unitScreenshots():Array { return _unitScreenshots; } public function set unitScreenshots(value:Array):void { _unitScreenshots = value; }
When I set a break point on both the getter and setter, only the getter method is being called, why? I would think that a push value on the array would trigger the setter, not the getter.
I've found two very strange pieces of code in PureMVC's documentation:
[Code]....
(found in Best Practices [English], bottom of page 38 and top of page 39) I've always thought that getters must not accept a parameter (and FDT indeed tells me that "Parameters for getters are not allowed"), so I wonder what's going on here. Is that just an unfortunate typo (meant to be simply a normal function without the "get") or some hidden feature/voodoo?
I'm trying to create a property that can be set by extending classed and read publicly.I couldn't think of a good naming convention for a protected property with a public getter, so I tried to do this:
public function get name():String{ return _name; } protected function set name(string:String):void {[code]......
However I get the error (when trying to set name in an extending class): 1178: Attempted access of inaccessible property name through a reference with static type testing:TestComponent.1059: Property is read-only.
I recently completed a tic-tac-toe game in AS3, using some simple function-based code I had written in C many years ago.Now I'm on a quest to do it the "right way" using OOP techniques and best practices.Everything is now divided into neat little packages, it looks pretty, and the last part of my journey is to get all the little buggers to communicate with each other.I want to move the code which holds the game state from my main to it's own class in com.okaygraphics.model.GameState.The problem is nearly every other package gets and sets these game state properties.I'm trying to figure out the simplest way to encapsulate this stuff, while still allowing my other classes to access it.
1) Do I need a constructor? I mean, my program will never have more than one GameState. If I should call my getters/setters as instance methods, how do I get each other class to reference the SAME instance from their respective packages?
2) Do I even need getters and setters? Perhaps the class could just have 3 public properties? If so, how would I acheive the proper scope with regard to my other classes?
3) Should I assign everything to the class itself using the static keyword? If so, how would I implement and use those static methods?
4) Is this a mistake? Did I totally just program myself into a corner?
Like I understand that if you're assigning something within a class it would have to involve what's extended to this class.So if a class extends MovieClip, would you only Set properties that involve the MovieClip object?Adversely, with Getter functions you could be retrieving anything from XML to volume. So that can't have anything to do with what that class is extending towards right?Is that how the extends relationship works with Get (return) and Set (value) functions?
I have two functions one that sets and one that gets a number. The set one works, but the get one doesn't. I have it trace the set it returns the correct number, but when I set the getY function, it doesn't give me anything at all. When i took the number out of the trace it just gave me back only text. What am I doing wrong here?
ActionScript Code: public function setY(y):void { y = y;
If I've got a getter method, say a(), that returns the private variable _a. Obviously from outside the class I call instanceOfClass.a. But from inside the class, should I use the getter or directly _a? Suppose I'm writing a method that uses _a: should I use _a or a? var b = a; or var b = _a? Maybe for performance reasons it's better to directly access _a? Or since there's a getter a(), it's a good practice using always and only the getter?
I have a document class .as file and I'm trying to communicate an object to another class with a getter. But it's nested inside another movie clip. The compiler says the movie clip it's nested in is undefined. Also, the moviecllip it's nested in is on the stage, dragged manually from the FLA LIbrary and has the instance name, gamelevel1 in the instance name box. I referred to it when I put the _player movie clip, which I'm trying to communicate with the getter, on the stage via and addChild method. Anyway here's the friggin' document class script:
I have written a class, which is basically a textfield for forms. It will eventually have several validation modes built into it too, which will be set by setting a property of the object.anyway, my problem. Basically my setters are empty if the movie is used as a loaded swf within another movie.I have an Event listener within the class listening for the Event.ACTIVATE event (still not sure exactly what this does...) though i do know that i need this in place for the setters/getters to work.If i create objects from my class, set some properties everything is spot on, though the moment i load this working movie into another movie the Event.ACTIVATE does not fire.[code]Now, if i run this movie its perfect - everything works as it should, right down to the validation.however, this movie is to be used within another movie. When i load this movie into a parent movie my fields aren't added to the movie.
I'm trying to make a class that extends the Sprite, have some private properties attached to it and be able to read and write those properties using getters and setters. Simple... but the compiler throw this error "Access of possibly undefined property speed through a reference with static type flash.display:Sprite."It works if I set my class to extend the MovieClip object.Could someone explain me the logic behind this? why I can't use getter and setters with a Sprite?Here is a sample code:
package { import flash.display.Sprite; public class Vehicle extends Sprite{
Getter functions allow obj.meth syntax instead of obj.meth(), I'd like to create an anonymous one of these to return from another function. function get ():Object { } is invalid syntax. I don't suppose Flex offers an easy way to get this functionality, if it's even possible?
I'm trying to make a class that extends the Sprite, have some private properties attached to it and be able to read and write those properties using getters and setters. Simple... but the compiler throw this error "Access of possibly undefined property speed through a reference with static type flash.display:Sprite."It works if I set my class to extend the MovieClip object. someone explain me the logic behind this? why I can't use getter and setters with a Sprite?
Is it possible to have a property with a public getter and protected setter? I have the following code:
public class Mob extends Sprite { // snip private var _health:Number; // tried making this protected, didn't work public function get health():Number { return _health; } protected function set health(value:Number):void {
[Code]...
I did have this.health -= dmg; but I split it out to get more details on the compiler errors. I don't understand how the property would be considered read-only within the same class. I also don't understand how it's inaccessible. If I make the backing field, getter, and setter all protected, it compiles but it's not the result I want; I need health to be readable externally.
I am start developing small games (I have just finished reading a nice book from Rex van der Spuy) but I would like to use the best OO approach.Let's make a very simple example: suppose that i have a Player class which adds a listener to the stage waiting for keyboard events in order to move around the stage.I have also some enemies on the stage and the player must register a collision with them; what is the best approach in order to access the enemies on the stage and check for a collision with them on the ENTER_FRAME player's event? I have read a lot of solutions, but I am just starting coding and so I don't know which one is the best approach.
a) Access the document class directly with a getter (e.g. Main(root).allEnemies, supposing that every time an enemy is created it is added to the allEnemies array)?
b) A singleton class which has a reference to every instance in the stage?
I have been assigned to work on a Java/Flash/BlazeDS project. When I pull down the project code, I need to run an Ant script as part of the setup. This script eventually compiles the Flash code, as seen below.[code]...
