L’esempio vale più di mille spiegazioni:

import mx.collections.ArrayCollection;
        import mx.utils.StringUtil;

        private static const DP_LENGTH:int = 100;
        private static const VISIBLE_ROWS_COUNT:int = 20;

        [Bindable]
        private var currentPage:int = 0;

        [Bindable]
        private var dataProvider:ArrayCollection;

        protected function init():void
        {
            var dpArray:Array = [];
            for (var i:int = 0; i < DP_LENGTH; i++)
            {
                var item:Object = { first: i, second: Math.random(), third: Math.random() };
                dpArray.push(item);
            }
            dataProvider = new ArrayCollection(dpArray);
            dataProvider.filterFunction = pagingFilterFunction;
            dataProvider.refresh();
        }

        protected function nextPage():void
        {
            currentPage++;
            dataProvider.refresh();
        }

        protected function prevPage():void
        {
            currentPage--;
            dataProvider.refresh();
        }

        private function pagingFilterFunction(item:Object):Boolean
        {
            var start:int = currentPage * VISIBLE_ROWS_COUNT;
            var end:int = start + VISIBLE_ROWS_COUNT - 1;
            var index:int = dataProvider.getItemIndex(item);
            return (index >= start) && (index <= end);
        }

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