Dynamic Row Heights with TanStack Virtual
Explain how to implement a list with dynamic row heights using TanStack Virtual, focusing on handling variability in content size.
import { useVirtualizer } from '@tanstack/react-virtual';
import { useRef } from 'react';
Import the necessary hooks from TanStack Virtual and React.
const parentRef = useRef();
Create a ref for the parent container.
const rowVirtualizer = useVirtualizer({
count: items.length,
getScrollElement: () => parentRef.current,
estimateSize: useCallback((index) => getItemHeight(index), []),
overscan: 5,
});
Initialize the virtualizer with the count of items, a method to get the scrollable element, an estimation function for item heights, and an overscan count.
const getItemHeight = index => {
// Implement logic to estimate the row's height
};
Define a function to estimate the height of each row based on its index.
<div ref={parentRef} style={{ overflow: 'auto', height: '100vh' }}>
<div style={{ height: `${rowVirtualizer.getTotalSize()}px`, width: '100%', position: 'relative' }}>
{rowVirtualizer.getVirtualItems().map(virtualRow => (
<div
key={virtualRow.key}
style={{
position: 'absolute',
top: 0,
left: 0,
width: '100%',
transform: `translateY(${virtualRow.start}px)`,
height: `${virtualRow.size}px`,
}}
>
{items[virtualRow.index]}
</div>
))}
</div>
</div>
Render the virtualized list inside the parent div. Each row is absolutely positioned within a relatively positioned container based on the virtualizer's calculations.