When onAdd function is triggered, new item dragged is already into the list

I am iterating all list elements in order to determine if the list already had the item I just droped into. I’m using Jquery:

$("#li").each(function(){ }

But the item just dropped is already there. Is there other event triggered before onAdd which would allow me to iterate list items before inserting the new item?

[romanrdgz]

Thanks for your answer.

Maybe my oppinion is worth 0, since I am a JS newbie, and this might be something obvious to everybody else. But I think this should really be explained at the documentation.

As it is currently explained, start event is triggered when I drag an element from list 1 (but haven’t dropped it yet over list 2). I have tested, and it does as suggested, so it doesn’t serve my purposes, because i need an event once the item has been dropped into list 2, but has not been included as an element of list 2 yet.

Then, sort event is explained as an event triggered on insert, update, or delete. I had tested this event, and I had seen that indeed it was triggered before the add event. But since the event is also triggered on update (which I guess is just a reordering of existing elements) and delete, logic would get mixed and become harder to maintain, so it does not look as the better choice. Moreover, when onSort is triggered, the dropped item has been inserted as an element as happened with onAdd, so again it does not solve my problem.

About add, as I have commented in my question, it is a late event for me, since the element has already been inserted to the list, and I am not able to iterate old list elements (unless I use HTML5 custom data to insert a flag into each item, but I think there must be a better and cleaner way to achieve this).

What I am trying to achieve, is to detect if the dropped element was already in the list, so I can avoid duplicates and increment the badge indicating the number of that element into the list. I do think this is an important feature, and current library status doesn’t allow an obvious way of getting this information. Please consider to add a feature for badge increment (for example using duplicates: false at Sortable list constructor) or at least improve documentation on events.

Therefore, is it possible to add a new event being triggered once an item is dropped into the list, but before that item becomes part of the list?

[omggga]

I have found 3 ways to prevent dropping item to the other list already contains that item.

• on start event get all collections, look for similar element and setting custom class for list element to prevent drop like @dandv said.
• on add event look for all elements in event.to list, and if there are more than 1 similar element, remove it
• on any start / end / update event look into result of Sortable.toArray() and then filter elements by uniq id

First way has a lower performance in working with large collections. Second and third have animation of drop and instant remove, so it looks like a bug.

Anyway, Sortable can provide you all you need on start and move events, but there ill be performance issues on checking duplicate elements.