VirtualScroll.md

VirtualScroll

Describes the header and cell contents of a table column

Prop Types

Property	Type	Required?	Description
className	String		CSS class name
height	Number	✓	Height constraint for list (determines how many actual rows are rendered)
noRowsRenderer		Function	Callback used to render placeholder content when rowsCount is 0
onRowsRendered		Function	Callback invoked with information about the slice of rows that were just rendered: ({ startIndex, stopIndex }): void
rowHeight	Number or Function	✓	Either a fixed row height (number) or a function that returns the height of a row given its index: (index: number): number
rowRenderer	Function	✓	Responsbile for rendering a row given an index. Signature should look like (index: number): React.PropTypes.node
rowsCount	Number	✓	Number of rows in list.
scrollToIndex	Number		Row index to ensure visible (by forcefully scrolling if necessary)

Public Methods

recomputeRowHeights

Recompute row heights and offsets.

VirtualScroll has no way of knowing when its underlying list data has changed since it only receives a rowHeight property. If the rowHeight is a number it can compare before and after values but if it is a function that comparison is error prone. In the event that a dynamic rowHeight function is in use and the row heights have changed this function should be manually called by the "smart" container parent.

scrollToRow

Scroll the list to ensure the row at the specified index is visible. This method exists so that a user can forcefully scroll to the same row twice. (The scrollToIndex property would not change in that case and so it would not be picked up by VirtualScroll.)

Class names

The VirtualScroll component supports the following static class names

Property	Description
VirtualScroll	Main (outer) element
VirtualScroll_innerScrollContainer	Inner element on which virtual items are positioned