Traversing display list hierarchies in an easier means, ala-AS2? (dot syntax)

I'm using all sprites because I don't need any dynamic nature to them and I'd like the UI to be as fast as possible so I really can't  use that dot notation unfortunately.

I come from c#, obj-c, perl, php, etc, very enumerated languages. When I do something like:

var a:Sprite = _container.getObjectByName('b');

That is not a property.

I am specifically adding a reference (and increasing the reference count to garbage collection) to the sprite who's name is 'b' that's contained in _container.

That's not a property, that is an object.

That is why it makes no sense to me when I can daisy chain operations in return-value style.

It is very much the same object nature that relates to functions. Nested functions use each others return values as arguments. Such as:

var num:Number = Math.round(Math.min(1.5,2.5));

Math.min returned 1, which Math.round accepts as a valid value to work with, which then rounds and returns to num. That was how you could traverse the display list before.

var cRef:Sprite = DisplayObjectContainer(a.getChildByName('b')).getChildByName('c');

That is not confusing and that is very much object oriented. The return value of a.getChildByName('b') returns to DisplayObjectContainer()'s scopeing function which then becomes a DisplayObjectContainer object that supports the method getChildByName('c'). There's nothing wrong with enclosing return values of objects methods into others.

I do a ton of *.graphics drawing all over my UI. I have a 500kb external XML file that I read in settings for about every aspect of the UI and all of it is generated in AS3. Lots of things are "just graphics", have no interaction and I have no need for them. But sometimes I'd like to affect them based on contextual situations and I always give them a name in the display list. I was just looking for a way to 1-line access those rare instances.

"What's the deal on this?"

It looks like there is a gap in understanding AS3 syntax and display list model AS3 uses.

1. Dot notation is allowed for objects's (class' which is an Object) PUBLIC (or protected in case of extended classes) properties/methods ONLY.

2. Members of display list ARE not properties just because they were placed into DIsplayObjectContainer hierarchy - thus they cannot be accessed as properties. In other words, there is a very clear separation between presentation and information layers in AS3. There are numerous benefits to this model. One of those benefits is that DisplayObjects can be moved around and loose/acquire parents without restriction but they NEVER loose scope they belong to.

Another VERY important thing re point 2 is that ONLY DisplayObject instances have an ability to be members of display lists. Other classes cannot be added but their public properties still can be accessed without any consideration given to dispaly list aspects.

With that said, as other guys suggested, in order to access an instance/property of anything directly one has to expose them explicitly to the outside scopes. Note that external scope is anything that doesn't belong to the current object's scope INCLUDING functions.

AS3 is a truley OO language and it is strict in how things are handled unlike AS2 where anything goes.

Because my class will build something dynamically in a loop using temporary variables.

import flash.display.Sprite;

for (var i:Number = 0; i < 100; i++)

{

   var someItem:Sprite = new Sprite();

   someItem.name = 'sprite' + i;

   addChild(someItem);

}

// someItem now out of context..

trace(sprite1.name); // Scene 1, Layer 'Layer 1', Frame 1, Line 13    1120: Access of undefined property sprite1.

Understand now? I'm dynamically generating hundreds of things in classes using loops.

Thus 'c' does not exist. I must traverse by name to get back to it or make a hard reference. I don't want to keep an array full of hard references to every graphic I draw.

Yes every sprite is named. As I mentioned, I figured out a way to daisy chain it together in one line using casting.

e.g.:

var a:Sprite() = new Sprite();

a.name = 'a';

addChild(a);

var b:Sprite = new Sprite();

b.name = 'b';

a.addChild(b);

var c:Sprite = new Sprite();

c.name = 'c';

b.addChild(c);

To get C in one line you can just:

var cRef:Sprite = Sprite(DisplayObjectContainer(a.getChildByName('b')).getChildByName('c'));

trace(cRef.name); // traces 'c'

I often make a global registry if I really need to share data or references if 'm being hacking but inside a class I always have tons of class-level variables that point to important portions of the UI. _navigation points directly to the sprite container that holds all my nav elements and I have a separate array _navItems[] with a reference to each individual nav item, etc.

Sometimes you just have a simple button somewhere and it's not really important enough to dedicate a class variable to it. I just wanted a quick 1-line way to traverse the display list and that seems to do it just fine by casting as I go (albeit ugly).

I've found that it is much easier to use event dispatchers to communicate between movie clip levels, especially when you don't know how to dig up through the parent hierarchy(which I've run into many times).

You can dispatch new events and use listeners to act upon what was dispatched. This can work from any level, any class, any mc, any external swf, any object etc.

i.e.:

//child move clip

dispatchEvent(new Event("Call_Prent_MovieClip"));

parentMovieClip.addEventListener("Call_Prent_MovieClip", callParent, true);

function sendColorString(e:Event):void
{  
      trace("Received call from child movie clip");
}

I personally don't use timelines at all and do everything with script so it doesn't matter to me, but as far as I'm aware nothing has changed in terms accessing nested MovieClips.

I have a MovieClip instance "movieclip1" on Stage. "movieclip1" contains a MovieClip instance "movieclip2". "movieclip2" contains a MovieClip instance "movieclip3".

From the main timeline:

trace(movieclip1.movieclip2.movieclip3);
// [object MovieClip]