Attempted to remove an unattached handler

[vyobukhov]

Hello,

I have two vertical collections on routes: /dialogs and /dialog/:id. The first one contains list of dialogs and the other one contains list of messages in this dialog.

Code of the first one (/dialogs):
{{#vertical-collection content=model defaultHeight=100 alwaysUseDefaultHeight=true useContentProxy=false as |item index| }} {{c-dialog model=item open="open"}} {{/vertical-collection}}

Code of the second one (/dialog/:id):
{{#vertical-collection content=messages defaultHeight=30 alwaysRemeasure=true renderFromLast=true as |item index| }} {{c-dialog-message model=item}} {{/vertical-collection}}

When I'm trying to go back from messages to dialogs (/dialogs => /dialog/1 => /dialogs) list I'm getting this error "Attempted to remove an unattached handler"

But when I'm navigating through one more route (for example /dialogs => /dialog/1 => /profile => /dialogs) everything works fine.

Is it bug? Or I'm doing something wrong?

[mszoernyi]

I've got a similar/same issue with two vertical-collections on one page. Doesn't seem to happen if only one is rendered at once.

For me it only happens if one of the tables is destroyed. We are setting a containerSelector which was the same for all tables but it doesn't seems to be related to this.

Debugging flow

1. _teardownHandlers() calls removeScrollHandler(this.telescope, this._scrollHandler) first without errors
2. _teardownHandlers() calls removeScrollHandler(Container, this._scrollAdjuster)
3. elementCache is {top: 0, left: 0, handlers: Array[0]} - shouldn't it have at least on adjust handler?
4. leads to the error itself

@vyobukhov maybe you can check if the debugger flow is the same for you. Given error is triggered in two different cases here and here

@runspired I'm not sure how to dig deeper?

[kylemellander]

does it seem like it would be viable to return inside returnElementHandler if the length of the handlers is 0. This would prevent this breaking error - and it doesn't seem like it would leave any handlers orphaned.

[eriktrom]

@kylemellander - yes that would fix error - but wondering @runspired's thoughts on GC perf issues - do the listeners still hold a reference that the browser engine will have to run GC cycles for? Or did ember tear them down already for us?

(have not read lib code at all, fyi) - but looking at options for new client's app that needs mobile infinite scroll - so might in future if this project seems active enough

[bloodknight2010]

I got the same error. I use smoke-and-mirrors version 0.6.2.But I can't. How to solve?

[rafaelbnp]

+1

[rafaelbnp]

I'm seeing this error when running my acceptance test, it breaks all my tests afterwards. Would really appreciate some help on how to fix it.

Error: Attempted to remove an unattached handler

[eriktrom]

the repo moved, try upgrading and use https://github.com/html-next/vertical-collection

[runspired]

Should be fixed by updating to @html-next/vertical-collection (now re-exported by this lib)