react-window-infinite-loader
InfiniteLoader component inspired by react-virtualized but for use with react-window
Install
# Yarn yarn add react-window-infinite-loader # NPM npm install --save react-window-infinite-loaderDocumentation
| Name | Type | Description |
|---|---|---|
children | ({ onItemsRendered: Function, ref: React$Ref }) => React$Node | Render prop. See below for example usage. |
isItemLoaded | (index: number) => boolean | Function responsible for tracking the loaded state of each item. |
itemCount | number | Number of rows in list; can be arbitrary high number if actual number is unknown. |
loadMoreItems | (startIndex: number, stopIndex: number) => Promise<void> | Callback to be invoked when more rows must be loaded. It should return a Promise that is resolved once all data has finished loading. |
minimumBatchSize | ?number | Minimum number of rows to be loaded at a time; defaults to 10. This property can be used to batch requests to reduce HTTP requests. |
threshold | ?number | Threshold at which to pre-fetch data; defaults to 15. A threshold of 15 means that data will start loading when a user scrolls within 15 rows. |
Example usage
The snippet below shows a basic example of how the InfiniteLoader can be used to wrap either a FixedSizeList or VariableSizeList from react-window.
// This value is arbitrary. // If you know the size of your remote data, you can provide a real value. // You can also increase this value gradually (as shown in the example below). const itemCount = 1000; <InfiniteLoader isItemLoaded={isItemLoaded} itemCount={itemCount} loadMoreItems={loadMoreItems} > {({ onItemsRendered, ref }) => ( <FixedSizeList itemCount={itemCount} onItemsRendered={onItemsRendered} ref={ref} {...otherListProps} /> )} </InfiniteLoader>Creating an infinite loading list
The InfiniteLoader component was created to help break large data sets down into chunks that could be just-in-time loaded as they were scrolled into view. It can also be used to create infinite loading lists (e.g. Facebook or Twitter). Here's a basic example of how you might implement that:
function ExampleWrapper({ // Are there more items to load? // (This information comes from the most recent API request.) hasNextPage, // Are we currently loading a page of items? // (This may be an in-flight flag in your Redux store for example.) isNextPageLoading, // Array of items loaded so far. items, // Callback function responsible for loading the next page of items. loadNextPage }) { // If there are more items to be loaded then add an extra row to hold a loading indicator. const itemCount = hasNextPage ? items.length + 1 : items.length; // Only load 1 page of items at a time. // Pass an empty callback to InfiniteLoader in case it asks us to load more than once. const loadMoreItems = isNextPageLoading ? () => {} : loadNextPage; // Every row is loaded except for our loading indicator row. const isItemLoaded = index => !hasNextPage || index < items.length; // Render an item or a loading indicator. const Item = ({ index, style }) => { let content; if (!isItemLoaded(index)) { content = "Loading..."; } else { content = items[index].name; } return <div style={style}>{content}</div>; }; return ( <InfiniteLoader isItemLoaded={isItemLoaded} itemCount={itemCount} loadMoreItems={loadMoreItems} > {({ onItemsRendered, ref }) => ( <FixedSizeList itemCount={itemCount} onItemsRendered={onItemsRendered} ref={ref} {...props} > {Item} </FixedSizeList> )} </InfiniteLoader> ); }License
MIT © bvaughn
