VirtualizedList #

Rendered when the list is empty. Can be a React Component Class, a render function, or a rendered element.

Rendered at the bottom of all the items. Can be a React Component Class, a render function, or a rendered element.

Rendered at the top of all the items. Can be a React Component Class, a render function, or a rendered element.

The default accessor functions assume this is an Array<{key: string}> but you can override getItem, getItemCount, and keyExtractor to handle any type of index-based data.

debug will turn on extra logging and visual overlays to aid with debugging both usage and implementation, but with a significant perf hit.

DEPRECATED: Virtualization provides significant performance and memory optimizations, but fully unmounts react instances that are outside of the render window. You should only need to disable this for debugging purposes.

A marker property for telling the list to re-render (since it implements PureComponent). If any of your renderItem, Header, Footer, etc. functions depend on anything outside of the data prop, stick it here and treat it immutably.

A generic accessor for extracting an item from any sort of data blob.

Determines how many items are in the data blob.

How many items to render in the initial batch. This should be enough to fill the screen but not much more. Note these items will never be unmounted as part of the windowed rendering in order to improve perceived performance of scroll-to-top actions.

Instead of starting at the top with the first item, start at initialScrollIndex. This disables the "scroll to top" optimization that keeps the first initialNumToRender items always rendered and immediately renders the items starting at this initial index. Requires getItemLayout to be implemented.

Reverses the direction of scroll. Uses scale transforms of -1.

The maximum number of items to render in each incremental render batch. The more rendered at once, the better the fill rate, but responsiveness my suffer because rendering content may interfere with responding to button taps or other interactions.

If provided, a standard RefreshControl will be added for "Pull to Refresh" functionality. Make sure to also set the refreshing prop correctly.

Called when the viewability of rows changes, as defined by the viewabilityConfig prop.

Set this true while waiting for new data from a refresh.

Note: may have bugs (missing content) in some circumstances - use at your own risk.

This may improve scroll performance for large lists.

Render a custom scroll component, e.g. with a differently styled RefreshControl.

Amount of time between low-pri item render batches, e.g. for rendering items quite a ways off screen. Similar fill rate/responsiveness tradeoff as maxToRenderPerBatch.

Determines the maximum number of items rendered outside of the visible area, in units of visible lengths. So if your list fills the screen, then windowSize={21} (the default) will render the visible screen area plus up to 10 screens above and 10 below the viewport. Reducing this number will reduce memory consumption and may improve performance, but will increase the chance that fast scrolling may reveal momentary blank areas of unrendered content.

Set this when offset is needed for the loading indicator to show correctly.