infinite scroll for fixed positioned divs angularjs

infiniteScroll.js

var mod;

mod = angular.module('infinite-scroll', []);

mod.directive('infiniteScroll', [
  '$rootScope', '$timeout', function($rootScope, $timeout) {
		return {
			link: function(scope, elem, attrs) {
				var checkWhenEnabled, handler, scrollDistance, scrollEnabled;

				$parent = angular.element(attrs.infiniteScrollParent);
				$child = angular.element(attrs.infiniteScrollChild);

				scrollDistance = 0;
				if (attrs.infiniteScrollDistance != null) {
					scope.$watch(attrs.infiniteScrollDistance, function(value) {
						return scrollDistance = parseInt(value, 10);
					});
				}
				scrollEnabled = true;
				checkWhenEnabled = false;
				if (attrs.infiniteScrollDisabled != null) {
					scope.$watch(attrs.infiniteScrollDisabled, function(value) {
						scrollEnabled = !value;
						if (scrollEnabled && checkWhenEnabled) {
							checkWhenEnabled = false;
							return handler();
						}
					});
				}
				handler = function() {
					var elementBottom, remaining, shouldScroll, windowBottom;

					windowBottom = $child.height() - $parent.scrollTop() - $parent.height();
					shouldScroll = windowBottom < scrollDistance;

					if (shouldScroll && scrollEnabled) {
						if ($rootScope.$$phase) {
							return scope.$eval(attrs.infiniteScroll);
						} else {
							return scope.$apply(attrs.infiniteScroll);
						}
					} else if (shouldScroll) {
						return checkWhenEnabled = true;
					}
				};

				$parent.on('scroll', handler);

				scope.$on('$destroy', function() {
					return $window.off('scroll', handler);
				});
				return $timeout((function() {
					if (attrs.infiniteScrollImmediateCheck) {
						if (scope.$eval(attrs.infiniteScrollImmediateCheck)) {
							return handler();
						}
					} else {
						return handler();
					}
				}), 0);
			}
		};
	}
]);

view.html

<div class='right-column-wrapper'>
		<div class='right-column-inner'>
        <div
    				infinite-scroll="nextConversations()"
  					infinite-scroll-disabled="busy"
  					infinite-scroll-distance="300"
  					infinite-scroll-parent=".right-column-wrapper"
  					infinite-scroll-child=".right-column-inner">
        </div>
    </div>
</div>