Interface: VirtuosoProps<D, C>
Extends
Type Parameters
• D
• C
Properties
alignToBottom?
optional
alignToBottom:boolean
Setting alignToBottom
to true
aligns the items to the bottom of the list if the list is shorter than the viewport.
Use followOutput
property to keep the list aligned when new items are appended.
atBottomStateChange()?
optional
atBottomStateChange: (atBottom
) =>void
Called with true / false when the list has reached the bottom / gets scrolled up.
Can be used to load newer items, like tail -f
.
Parameters
atBottom
boolean
Returns
void
atBottomThreshold?
optional
atBottomThreshold:number
The property accepts pixel values.
By default 4
. Redefine to change how much away from the bottom the scroller can be before the list is not considered not at bottom.
atTopStateChange()?
optional
atTopStateChange: (atTop
) =>void
Called with true
/ false
when the list has reached the top / gets scrolled down.
Parameters
atTop
boolean
Returns
void
atTopThreshold?
optional
atTopThreshold:number
The property accepts pixel values.
By default 0
. Redefine to change how much away from the top the scroller can be before the list is not considered not at top.
components?
optional
components:Components
<D
,C
>
Use the components
property for advanced customization of the elements rendered by the list.
computeItemKey?
optional
computeItemKey:ComputeItemKey
<D
,C
>
If specified, the component will use the function to generate the key
property for each list item.
context?
optional
context:C
Additional context available in the custom components and content callbacks
customScrollParent?
optional
customScrollParent:HTMLElement
Pass a reference to a scrollable parent element, so that the list won't wrap in its own.
data?
optional
data: readonlyD
[]
The data items to be rendered. If data is set, the total count will be inferred from the length of the array.
defaultItemHeight?
optional
defaultItemHeight:number
By default, the component assumes the default item height from the first rendered item (rendering it as a "probe").
If the first item turns out to be an outlier (very short or tall), the rest of the rendering will be slower, as multiple passes of rendering should happen for the list to fill the viewport.
Setting defaultItemHeight
causes the component to skip the "probe" rendering and use the property
value as default height instead.
endReached()?
optional
endReached: (index
) =>void
Gets called when the user scrolls to the end of the list. Receives the last item index as an argument. Can be used to implement endless scrolling.
Parameters
index
number
Returns
void
firstItemIndex?
optional
firstItemIndex:number
Use when implementing inverse infinite scrolling - decrease the value this property
in combination with data
or totalCount
to prepend items to the top of the list.
Warning: the firstItemIndex should be a positive number, based on the total amount of items to be displayed.
fixedItemHeight?
optional
fixedItemHeight:number
Can be used to improve performance if the rendered items are of known size. Setting it causes the component to skip item measurements.
followOutput?
optional
followOutput:FollowOutput
If set to true
, the list automatically scrolls to bottom if the total count is changed.
Set to "smooth"
for an animated scrolling.
By default, followOutput
scrolls down only if the list is already at the bottom.
To implement an arbitrary logic behind that, pass a function:
<Virtuoso
followOutput={(isAtBottom: boolean) => {
if (expression) {
return 'smooth' // can be 'auto' or false to avoid scrolling
} else {
return false
}
}} />
headerFooterTag?
optional
headerFooterTag:string
Set to customize the wrapper tag for the header and footer components (default is div
).
horizontalDirection?
optional
horizontalDirection:boolean
When set, turns the scroller into a horizontal list. The items are positioned with inline-block
.
increaseViewportBy?
optional
increaseViewportBy:number
| {bottom
:number
;top
:number
; }
The property accepts pixel values.
Set the increaseViewportBy property to artificially increase the viewport size, causing items to be rendered before outside of the viewport.
The property causes the component to render more items than the necessary, but can help with slow loading content.
Using { top?: number, bottom?: number }
lets you set the increase for each end separately.
initialItemCount?
optional
initialItemCount:number
Use for server-side rendering - if set, the list will render the specified amount of items regardless of the container / item size.
initialScrollTop?
optional
initialScrollTop:number
Set this value to offset the initial location of the list.
Warning: using this property will still run a render cycle at the scrollTop: 0 list window.
If possible, avoid using it and stick to initialTopMostItemIndex
instead.
initialTopMostItemIndex?
optional
initialTopMostItemIndex:number
|IndexLocationWithAlign
Set to a value between 0 and totalCount - 1 to make the list start scrolled to that item.
Pass in an object to achieve additional effects similar to scrollToIndex
.
isScrolling()?
optional
isScrolling: (isScrolling
) =>void
Called when the list starts/stops scrolling.
Parameters
isScrolling
boolean
Returns
void
itemContent?
optional
itemContent:ItemContent
<D
,C
>
Set the callback to specify the contents of the item.
itemSize?
optional
itemSize:SizeFunction
Allows customizing the height/width calculation of Item
elements.
The default implementation reads el.getBoundingClientRect().height
and el.getBoundingClientRect().width
.
itemsRendered()?
optional
itemsRendered: (items
) =>void
Called with the new set of items each time the list items are rendered due to scrolling.
Parameters
items
ListItem
<D
>[]
Returns
void
logLevel?
optional
logLevel:LogLevel
set to LogLevel.DEBUG to enable various diagnostics in the console, the most useful being the item measurement reports.
Ensure that you have "all levels" enabled in the browser console too see the messages.
overscan?
optional
overscan:number
| {main
:number
;reverse
:number
; }
The property accepts pixel values.
Set the overscan property to make the component "chunk" the rendering of new items on scroll.
The property causes the component to render more items than the necessary, but reduces the re-renders on scroll.
Setting { main: number, reverse: number }
lets you extend the list in both the main and the reverse scrollable directions.
See the increaseViewportBy
property for a similar behavior (equivalent to the overscan
in react-window).
rangeChanged()?
optional
rangeChanged: (range
) =>void
Called with the new set of items each time the list items are rendered due to scrolling.
Parameters
range
Returns
void
restoreStateFrom?
optional
restoreStateFrom:StateSnapshot
pass a state obtained from the getState() method to restore the list state - this includes the previously measured item sizes and the scroll location. Notice that you should still pass the same data and totalCount properties as before, so that the list can match the data with the stored measurements. This is useful when you want to keep the list state when the component is unmounted and remounted, for example when navigating to a different page.
scrollerRef()?
optional
scrollerRef: (ref
) =>any
Provides access to the root DOM element
Parameters
ref
null
| HTMLElement
| Window
Returns
any
scrollSeekConfiguration?
optional
scrollSeekConfiguration:false
|ScrollSeekConfiguration
Use to display placeholders if the user scrolls fast through the list.
Set components.ScrollSeekPlaceholder
to change the placeholder content.
skipAnimationFrameInResizeObserver?
optional
skipAnimationFrameInResizeObserver:boolean
When set, the resize observer used to measure the items will not use requestAnimationFrame
to report the size changes.
Setting this to true will improve performance and reduce flickering, but will cause benign errors to be reported in the console if the size of the items changes while they are being measured.
See https://github.com/petyosi/react-virtuoso/issues/1049 for more information.
startReached()?
optional
startReached: (index
) =>void
Called when the user scrolls to the start of the list.
Parameters
index
number
Returns
void
topItemCount?
optional
topItemCount:number
Set the amount of items to remain fixed at the top of the list.
For a header that scrolls away when scrolling, check the components.Header
property.
totalCount?
optional
totalCount:number
The total amount of items to be rendered.
totalListHeightChanged()?
optional
totalListHeightChanged: (height
) =>void
Called when the total list height is changed due to new items or viewport resize.
Parameters
height
number
Returns
void
useWindowScroll?
optional
useWindowScroll:boolean
Uses the document scroller rather than wrapping the list in its own.
start?
optional
start:number
Inherited from
ListRootProps.start
cite?
optional
cite:string
Inherited from
ListRootProps.cite
form?
optional
form:string
Inherited from
ListRootProps.form
label?
optional
label:string
Inherited from
ListRootProps.label
slot?
optional
slot:string
Inherited from
ListRootProps.slot
span?
optional
span:number
Inherited from
ListRootProps.span
style?
optional
style:CSSProperties
Inherited from
ListRootProps.style
summary?
optional
summary:string
Inherited from
ListRootProps.summary
title?
optional
title:string
Inherited from
ListRootProps.title
pattern?
optional
pattern:string
Inherited from
ListRootProps.pattern
children?
optional
children:ReactNode
Inherited from
ListRootProps.children
tabIndex?
optional
tabIndex:number