synchronized scrolling of an arbitrary number of elements (this one is focused on y axis)

1-sync-scrolling.js

var scrollWatches = {};
var setupScrollWatch = function(id, _el){
	if (!scrollWatches[id]){
		scrollWatches[id] = [];
	}
	if (_.indexOf(scrollWatches[id], _el) == -1){
		scrollWatches[id].push(_el);
		$(_el).scroll(function(a,b){
			syncToScroll(id, _el);
		});
		return true;
	}
	return false;
}
var syncToScroll = function(id, _el){
	var scrollTop = _el.scrollTop();
	_.each(scrollWatches[id], function(_el_pair){
		if (-el != _el_pair){
			_el_pair.scrollTop(scrollTop);
		}
	});
}

2-helpers.js

scope.syncToCfScroll = function(){
	var id = 'cf-y';
	_.each( el.find('.t-sync-to-cf-panel'), function(_el){
		setupScrollWatch( id, $(_el) );
	});
	setTimeout(function(){
		syncToScroll( id, $(elselect('curriculum_framework_list')) );
	}, 20)
}
var  setupCFScrollWatch = function(){
	var _el = elselect('curriculum_framework_list');
	setupScrollWatch('cf-y', _el);	
}