Populate list box other than for loop

1

I’ll start with some background to my query.
Listbox is the simple most example I can take to explain things.

I don’t know how to frame my query but i’ll try to be as specific as possible.

Let’s say I have an xml file which I load into my flash app and then populate a listbox with it.
So I’ll take following steps

  1. load xml file
  2. parse xml file and make an array of items to be put in listbox
  3. loop through the array and populate the listbox (basically attachMovie)

Now for step 3 I have been using for loop. This is ok if there are small number of items in a list box. But when the list is quite long (say 200 to 500 items) there is certain lag.

same paradigm applies if I have to put different graphic elements on a blank board dynamically.

Is there any way wherein you can populate/add mcs to listbox kind of thing at interval so that it appears to be loading dynamically one after another.