Comments on: Collections API update

By: Alan

Alan — Thu, 04 Feb 2010 23:32:05 +0000

Hi Eric,
Does HashMap suport data binding? I want to bind a hashmap value to a textinput component.

Thanks,
Alan

By: eric

eric — Mon, 20 Oct 2008 14:39:06 +0000

Hey Charisma,

You will get inconsistent results because internally, the HashMap utilizes a Dictionary object, thus when you invoke HashMapA.getEntries(); the underlying algorithm uses a “for in” loop, which when used to iterate over an Object or Dictionary the order of the results returned are not guaranteed.

Best,
Eric

By: charisma

charisma — Mon, 20 Oct 2008 09:07:18 +0000

mapEntry = iList.getItemAt(i) as HashMapEntry;
HashMapB = mapEntry.value;
tmpList = HashMapB.getEntries();
tmpListLen = tmpList.length;
trace(”i -> ” + i + ” ” + mapEntry.key + ” ” + tmpListLen);

errr, i can’t post my for-loop properly

By: charisma

charisma — Mon, 20 Oct 2008 09:04:46 +0000

Sorry, this should be the content of the for-loop:

for (var i:int=0; i ” + i + ” ” + mapEntry.key + ” ” + tmpListLen);
}

By: charisma

charisma — Mon, 20 Oct 2008 09:03:32 +0000

Hmmm. In my code I got HashMap object and put it as a value inside another HashMap. Looks like this: HashMapA(key, HashMapB value).

Then i do:

var iList:IList = HashMapA.getEntries();
var iListLen:int = iList.length;
var mapEntry:HashMapEntry = null;

var tmpList:IList = null;
var HashMapB:HashMap = null;
var tmpListLen:int = 0;

for (var i:int=0; i ” + i + ” ” + mapEntry.key + ” ” + tmpListLen);
}

If you run this code repeatedly, you will notice that tmpListLen yields inconsistent results.

By: mark

mark — Wed, 08 Oct 2008 06:35:11 +0000

One more thing - looking inside the HashMap class, I could not see any kind of hashing going on - or is that something built into Actionscript’s property lookup mechanism?

By: mark

mark — Fri, 26 Sep 2008 06:01:04 +0000

Thanks very much for these - saved me a lot of typing.

Small problem…

If I do something like mymap.put(”hello”, null) and then mymap.contains(”hello”), it returns false. This is because for “contains()” you implemented it by checking the value in the dictionary. Is it possible to change this so that contains() tests for the existing of the key rather than the null-ness of the value???

Would hasOwnProperty() do this???

By: charisma

charisma — Thu, 25 Sep 2008 08:52:58 +0000

HashMap utility is very helpful. Thanks!

By: eric

eric — Sun, 06 Jul 2008 15:41:38 +0000

I have an entire codebase which contains all of my Open Source APIs as well as numerous other APIs which are not open source. This is entirely under version control and provides source access and distributions. If you are interested in the licensed version you can contact me directly

Thanks,
Eric

By: jadd

jadd — Sat, 05 Jul 2008 09:51:30 +0000

hi Eric,
and thanks for sharing your work. Could be nice to see all your code in a repository indeed, much easier to update for us.
Thanks.

By: Luca

Luca — Wed, 23 Apr 2008 09:43:08 +0000

One problem with:
getEntries() : IList;
(and the ArrayCollection) is that it introduces a dependency on the Flex framework, preventing the use of you HashMap in plain AS3 projects
Any chance of changing it to an Array?

By: eric

eric — Thu, 03 Apr 2008 18:00:39 +0000

Hey Maz,

I agree, for the most part these are common APIs one would expect to be included in the framework. The only reason I can think of as to why they are not included is to allow ActionScript 3 to align with the ECMA-262 edition 4 standard - which in many ways is very limiting.

- Eric