Summary:
We really need a better list view - so here it is!
Main changes from existing `ListView`:
* Items are "virtualized" to limit memory - that is, items outside of the render window are unmounted and their memory is reclaimed. This means that instance state is not preserved when items scroll out of the render window.
* No `DataSource` - just a simple `data` prop of shape `Array<any>`. By default, they are expected to be of the shape `{key: string}` but a custom `rowExtractor` function can be provided for different shapes, e.g. graphql data where you want to map `id` to `key`. Note the underlying `VirtualizedList` is much more flexible.
* Fancy `scrollTo` functionality: `scrollToEnd`, `scrollToIndex`, and `scrollToItem` in addition to the normal `scrollToOffset`.
* Built-in pull to refresh support - set set the `onRefresh` and `refreshing` props.
* Rendering additional rows is usually done with low priority, after any interactions/animations complete, unless we're about to run out of rendered content. This should help apps feel more responsive.
* Component props replace render functions, e.g. `ItemComponent: ReactClass<{item: Item, index: number}>` replaces `renderRow: (...) => React.Element<*>`
* Supports dynamic items automatically by using `onLayout`, or `getItemLayout` can be provided for a perf boost and smoother `scrollToIndex` and scroll bar behavior.
* Visibility callback replaced with more powerful viewability callback and works in vertical and horizontal mode on at least Android and iOS, but probably other platforms as well. Extra power comes from the `viewablePercentThreshold` that lets the client decide when an item should be considered viewable.
Demo:
https://www.facebook.com/groups/576288835853049/permalink/753923058089625/
Reviewed By: yungsters
Differential Revision: D4412469
fbshipit-source-id: e2d891490bf76fe14df49294ecddf78a58adcf23
Summary:
- Replace some fixes that were accidentally lost in local rebase that prevent jumpiness when incremental is disabled.
- Require each row to have a key specified by the caller to prevent jumping because of accidental duplicates or unneeded/problematic row re-rendering because of legit re-ordering.
Reviewed By: steveluscher
Differential Revision: D3322006
fbshipit-source-id: 0019aab07cb1fe2b148a14b5818de53aa373eb50
Summary:`WindowedListView` is designed for memory efficient scrolling of
huge/infinite lists of variable height rows. It works by measuring row heights
with `onLayout` and caching the results, then unmounting rows that scroll
offscreen, replacing them with an equivalent offset in the spacer view. Care is
taken to render a constant number of rows, and to only render one new row per
tick to improve framerate and app responsiveness. WLV is also compatible with
<Incremental> used within the rows themselves.
`WindowedListView` is not a drop-in replacement for `ListView` - it doesn't
support many of the features of `ListView`, such as section headers, only
accepts a simple array of data instead of a datasource, and doesn't support
horizontal scrolling. This may change in the future.
This is still experimental - we haven't deployed this for any production apps
yet.
Differential Revision: D2791402
fb-gh-sync-id: 5f104e0903f6ba586d2d651bdf82863a231279d8
fbshipit-source-id: 5f104e0903f6ba586d2d651bdf82863a231279d8
