Yeah, I second this suggestion. IViewCursor is your friend :)
And I know I haven't added much to the discussion -- but I want to
contribute, not just leech off everyone!
You guys are too quick to reply!
:)
On Tue, Nov 25, 2008 at 16:15, gabriel montagné
<[EMAIL PROTECTED]>wrote:
> On Mon, Nov 24, 2008 at 3:45 AM, bjorn <[EMAIL
> PROTECTED]<itrashmail%40gmail.com>>
> wrote:
> > No one knows the answer to my initial question about why there is a
> problem
> > implementing removeItemAt()/addItemAt() on a sorted AC?
>
> Well, the cool thing about using those mx.collections.* classes, as opposed
> to, for example, just using Arrays (besides binding, that is) is using a
> cursor view of them so you don't really have to go counting with your
> fingers
> where a particular item is.
>
> If you have a sorted collection (of Point objects, lets say), you can
> create a
> cursor and use that to find, remove, etc. whatever it is that you're
> looking
> for.
>
> You can quickly do stuff like:
>
> // sort the items first by x, in descending order, then by y ascending
> // (without cumbersome Array sort functions).
>
> var customSort:Sort = new Sort();
> customSort.fields = [
> new SortField("x", false, true),
> new SortField("y")
> ];
> collection.sort = customSort;
> collection.refresh();
>
> // later on, you need to find the first point, according to this order,
> which
> // has and x of 160 and and y of 130. Instead of looping through the set,
> // you can use a cursor like this:
>
> var cursor:IViewCursor = collection.createCursor();
> var itemFound:Boolean = cursor.findFirst({x:160, y:130})
>
> // now your cursor is pointing to the item you're looking for (you can
> check
> // on it by looking at the 'current' property), if it has found it. Without
> // having to worry on which index it was, you can just then say:
>
> if (itemFound)
> cursor.remove();
>
> This is just a simple example of the sort of things that you should be
> using
> collections for. I'd suggest a quick glance over the IViewCursor docs to
> see
> how cool that approach is. Remember that collections (like ArrayCollection,
> for example) are just particular views of rawer data sets; Their aim is
> just
> to make your life simpler in the end.
>
> HTH,
>
> --
> gabriel montagné láscaris comneno
> http://rojored.com
> t/506.8367.6794
>
>
