import * as React from 'react'
import * as ReactDOM from 'react-dom/client'
import './index.css'
import { useVirtualizer } from '@tanstack/react-virtual'
function App() {
return (
<div>
<p>
These components are using <strong>fixed</strong> sizes. This means that
every element's dimensions are hard-coded to the same value and never
change.
</p>
<br />
<br />
<h3>Rows</h3>
<RowVirtualizerFixed />
<br />
<br />
<h3>Columns</h3>
<ColumnVirtualizerFixed />
<br />
<br />
<h3>Grid</h3>
<GridVirtualizerFixed />
<br />
<br />
{process.env.NODE_ENV === 'development' ? (
<p>
<strong>Notice:</strong> You are currently running React in
development mode. Rendering performance will be slightly degraded
until this application is built for production.
</p>
) : null}
</div>
)
}
function RowVirtualizerFixed() {
const parentRef = React.useRef(null)
const rowVirtualizer = useVirtualizer({
count: 10000,
getScrollElement: () => parentRef.current,
estimateSize: () => 35,
overscan: 5,
})
return (
<>
<div
ref={parentRef}
className="List"
style={{
height: `200px`,
width: `400px`,
overflow: 'auto',
}}
>
<div
style={{
height: `${rowVirtualizer.getTotalSize()}px`,
width: '100%',
position: 'relative',
}}
>
{rowVirtualizer.getVirtualItems().map((virtualRow) => (
<div
key={virtualRow.index}
className={virtualRow.index % 2 ? 'ListItemOdd' : 'ListItemEven'}
style={{
position: 'absolute',
top: 0,
left: 0,
width: '100%',
height: `${virtualRow.size}px`,
transform: `translateY(${virtualRow.start}px)`,
}}
>
Row {virtualRow.index}
</div>
))}
</div>
</div>
</>
)
}
function ColumnVirtualizerFixed() {
const parentRef = React.useRef(null)
const columnVirtualizer = useVirtualizer({
horizontal: true,
count: 10000,
getScrollElement: () => parentRef.current,
estimateSize: () => 100,
overscan: 5,
})
return (
<>
<div
ref={parentRef}
className="List"
style={{
width: `400px`,
height: `100px`,
overflow: 'auto',
}}
>
<div
style={{
width: `${columnVirtualizer.getTotalSize()}px`,
height: '100%',
position: 'relative',
}}
>
{columnVirtualizer.getVirtualItems().map((virtualColumn) => (
<div
key={virtualColumn.index}
className={
virtualColumn.index % 2 ? 'ListItemOdd' : 'ListItemEven'
}
style={{
position: 'absolute',
top: 0,
left: 0,
height: '100%',
width: `${virtualColumn.size}px`,
transform: `translateX(${virtualColumn.start}px)`,
}}
>
Column {virtualColumn.index}
</div>
))}
</div>
</div>
</>
)
}
function GridVirtualizerFixed() {
const parentRef = React.useRef(null)
const rowVirtualizer = useVirtualizer({
count: 10000,
getScrollElement: () => parentRef.current,
estimateSize: () => 35,
overscan: 5,
})
const columnVirtualizer = useVirtualizer({
horizontal: true,
count: 10000,
getScrollElement: () => parentRef.current,
estimateSize: () => 100,
overscan: 5,
})
return (
<>
<div
ref={parentRef}
className="List"
style={{
height: `500px`,
width: `500px`,
overflow: 'auto',
}}
>
<div
style={{
height: `${rowVirtualizer.getTotalSize()}px`,
width: `${columnVirtualizer.getTotalSize()}px`,
position: 'relative',
}}
>
{rowVirtualizer.getVirtualItems().map((virtualRow) => (
<React.Fragment key={virtualRow.key}>
{columnVirtualizer.getVirtualItems().map((virtualColumn) => (
<div
key={virtualColumn.key}
className={
virtualColumn.index % 2
? virtualRow.index % 2 === 0
? 'ListItemOdd'
: 'ListItemEven'
: virtualRow.index % 2
? 'ListItemOdd'
: 'ListItemEven'
}
style={{
position: 'absolute',
top: 0,
left: 0,
width: `${virtualColumn.size}px`,
height: `${virtualRow.size}px`,
transform: `translateX(${virtualColumn.start}px) translateY(${virtualRow.start}px)`,
}}
>
Cell {virtualRow.index}, {virtualColumn.index}
</div>
))}
</React.Fragment>
))}
</div>
</div>
</>
)
}
// eslint-disable-next-line
ReactDOM.createRoot(document.getElementById('root')!).render(
<React.StrictMode>
<App />
</React.StrictMode>,
)
import * as React from 'react'
import * as ReactDOM from 'react-dom/client'
import './index.css'
import { useVirtualizer } from '@tanstack/react-virtual'
function App() {
return (
<div>
<p>
These components are using <strong>fixed</strong> sizes. This means that
every element's dimensions are hard-coded to the same value and never
change.
</p>
<br />
<br />
<h3>Rows</h3>
<RowVirtualizerFixed />
<br />
<br />
<h3>Columns</h3>
<ColumnVirtualizerFixed />
<br />
<br />
<h3>Grid</h3>
<GridVirtualizerFixed />
<br />
<br />
{process.env.NODE_ENV === 'development' ? (
<p>
<strong>Notice:</strong> You are currently running React in
development mode. Rendering performance will be slightly degraded
until this application is built for production.
</p>
) : null}
</div>
)
}
function RowVirtualizerFixed() {
const parentRef = React.useRef(null)
const rowVirtualizer = useVirtualizer({
count: 10000,
getScrollElement: () => parentRef.current,
estimateSize: () => 35,
overscan: 5,
})
return (
<>
<div
ref={parentRef}
className="List"
style={{
height: `200px`,
width: `400px`,
overflow: 'auto',
}}
>
<div
style={{
height: `${rowVirtualizer.getTotalSize()}px`,
width: '100%',
position: 'relative',
}}
>
{rowVirtualizer.getVirtualItems().map((virtualRow) => (
<div
key={virtualRow.index}
className={virtualRow.index % 2 ? 'ListItemOdd' : 'ListItemEven'}
style={{
position: 'absolute',
top: 0,
left: 0,
width: '100%',
height: `${virtualRow.size}px`,
transform: `translateY(${virtualRow.start}px)`,
}}
>
Row {virtualRow.index}
</div>
))}
</div>
</div>
</>
)
}
function ColumnVirtualizerFixed() {
const parentRef = React.useRef(null)
const columnVirtualizer = useVirtualizer({
horizontal: true,
count: 10000,
getScrollElement: () => parentRef.current,
estimateSize: () => 100,
overscan: 5,
})
return (
<>
<div
ref={parentRef}
className="List"
style={{
width: `400px`,
height: `100px`,
overflow: 'auto',
}}
>
<div
style={{
width: `${columnVirtualizer.getTotalSize()}px`,
height: '100%',
position: 'relative',
}}
>
{columnVirtualizer.getVirtualItems().map((virtualColumn) => (
<div
key={virtualColumn.index}
className={
virtualColumn.index % 2 ? 'ListItemOdd' : 'ListItemEven'
}
style={{
position: 'absolute',
top: 0,
left: 0,
height: '100%',
width: `${virtualColumn.size}px`,
transform: `translateX(${virtualColumn.start}px)`,
}}
>
Column {virtualColumn.index}
</div>
))}
</div>
</div>
</>
)
}
function GridVirtualizerFixed() {
const parentRef = React.useRef(null)
const rowVirtualizer = useVirtualizer({
count: 10000,
getScrollElement: () => parentRef.current,
estimateSize: () => 35,
overscan: 5,
})
const columnVirtualizer = useVirtualizer({
horizontal: true,
count: 10000,
getScrollElement: () => parentRef.current,
estimateSize: () => 100,
overscan: 5,
})
return (
<>
<div
ref={parentRef}
className="List"
style={{
height: `500px`,
width: `500px`,
overflow: 'auto',
}}
>
<div
style={{
height: `${rowVirtualizer.getTotalSize()}px`,
width: `${columnVirtualizer.getTotalSize()}px`,
position: 'relative',
}}
>
{rowVirtualizer.getVirtualItems().map((virtualRow) => (
<React.Fragment key={virtualRow.key}>
{columnVirtualizer.getVirtualItems().map((virtualColumn) => (
<div
key={virtualColumn.key}
className={
virtualColumn.index % 2
? virtualRow.index % 2 === 0
? 'ListItemOdd'
: 'ListItemEven'
: virtualRow.index % 2
? 'ListItemOdd'
: 'ListItemEven'
}
style={{
position: 'absolute',
top: 0,
left: 0,
width: `${virtualColumn.size}px`,
height: `${virtualRow.size}px`,
transform: `translateX(${virtualColumn.start}px) translateY(${virtualRow.start}px)`,
}}
>
Cell {virtualRow.index}, {virtualColumn.index}
</div>
))}
</React.Fragment>
))}
</div>
</div>
</>
)
}
// eslint-disable-next-line
ReactDOM.createRoot(document.getElementById('root')!).render(
<React.StrictMode>
<App />
</React.StrictMode>,
)
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