vertical-collection
Infinite Scroll and Occlusion at > 60FPS
vertical-collection
is an ember-addon
that is part of the smoke-and-mirrors
framework. It
focuses on improving initial and re-render performance in high-stress situations by providing a
component for performant lists and svelte renders
to match a core belief:
Don't render the universe, render the scene.
TL;DR svelte render: the fewer things you need to render, the faster your renders will be.
Your web page is a universe, your viewport is the scene. Much like you wouldn't expect a video game to render
out-of-scene content, your application should smartly cull the content it doesn't need to care about. Trimming
excess content lets the browser perform both initial renders and re-renders at far higher frame-rates, as the only
content it needs to focus on for layout is the content the user can see.
vertical-collection
augments your existing app, it doesn't ask you to rewrite layouts or logic in order to use it.
It will try its best to allow you to keep the conventions, structures, and layouts you want.
Install
ember install @html-next/vertical-collection
Usage
<VerticalCollection
@items={{items}}
@tagName="ul"
@estimateHeight={{50}}
@staticHeight={{false}}
@bufferSize={{1}}
@renderAll={{false}}
@renderFromLast={{false}}
@idForFirstItem={{idForFirstItem}}
@firstReached={{firstReachedCallback}}
@lastReached={{lastReachedCallback}}
@firstVisibleChanged={{firstVisibleChangedCallback}}
@lastVisibleChanged={{lastVisibleChangedCallback}}
as |item i|>
<li>
{{item.number}} {{i}}
</li>
</VerticalCollection>
Actions
firstReached
- Triggered when scroll reaches the first element in the collection
lastReached
- Triggered when scroll reaches the last element in the collection
firstVisibleChanged
- Triggered when the first element in the viewport changes
lastVisibleChanged
- Triggered when the last element in the viewport changes
Support Matrix
vertical-collection version | Supported Ember versions | Supported Node versions |
---|
^v1.x.x | v1.12.0 - v3.8.x | ? |
^v2.x.x | v2.8.0 - v3.26.x | v12 - ? |
^v3.x.x | v2.18.0+ | v14+ |
^v4.x.x | v3.12.0+ | v14+ |
Support, Questions, Collaboration
Join the Ember community on Discord
Features
Infinite Scroll (bi-directional)
Infinite scroll that remains performant even for very long lists is easily achievable
with the vertical-collection
.
It works via a scrollable div or scrollable body.
Svelte Everything
If it can be trimmer, vertical-collection likes to trim it.
Status
Changelog
Documentation
For updated documentation and demos see http://html-next.github.io/vertical-collection/
Contributing
- Open an Issue for discussion first if you're unsure a feature/fix is wanted.
- Branch off of
master
(default branch) - Use descriptive branch names (e.g.
<type>/<short-description>
) - PR against
master
(default branch).
Testing
Make sure you register the test waiter from ember-raf-scheduler. So ember-test-helpers
's wait
is aware of the scheduled updates.
An example can be found here
License
This project is licensed under the MIT License.