ant-design/components/affix/index.en-US.md

category	type	title	cover
Components	Navigation	Affix	https://gw.alipayobjects.com/zos/alicdn/tX6-md4H6/Affix.svg

Wrap Affix around another component to make it stick the viewport.

When To Use

On longer web pages, its helpful for some content to stick to the viewport. This is common for menus and actions.

Please note that Affix should not cover other content on the page, especially when the size of the viewport is small.

API

Property	Description	Type	Default
offsetBottom	Offset from the bottom of the viewport (in pixels)	number	-
offsetTop	Offset from the top of the viewport (in pixels)	number	0
target	Specifies the scrollable area DOM node	() => HTMLElement	() => window
onChange	Callback for when Affix state is changed	function(affixed)	-

Note: Children of Affix must not have the property position: absolute, but you can set position: absolute on Affix itself:

<Affix style={{ position: 'absolute', top: y, left: x }}>...</Affix>

FAQ

Affix bind container with target, sometime move out of container.

We don't listen window scroll for performance consideration. You can add listener if you still want: https://codesandbox.io/s/2xyj5zr85p

Related issues：#3938 #5642 #16120