react-float-anchor

react-float-anchor

This is a React component for anchoring a fixed position element, such as a dropdown menu, to the edge of an element on the page. The fixed position element will automatically be placed so that it fits on the screen if possible, and it will automatically reposition if needed when the user scrolls.

The above example can be tried here:

https://streakyc.github.io/react-float-anchor/example/

You can find its code in the example directory. The example may be compiled by running:

npm install
npm run example-build

You can build the example with live editing enabled (using react-transform-hmr and browserify-hmr) by running:

npm run example-watch

FloatAnchor

This module exports the FloatAnchor React component, which takes the following props:

• anchor must be a single React Element. This element will be placed in the page where the FloatAnchor element was used, with no added wrapper elements around it.
• float must be null or a single React Element. This element will be placed in a container div which has position:fixed styling, is attached directly to the document body, and is positioned to line up with the anchor element.
• options is an optional object of options to control how the float element's container is aligned to the anchor element. The options are the same as those supported by contain-by-screen (version ^1.0).
• zIndex is an optional number controlling the z-index CSS property of the float element's container.

FloatAnchor has the following static methods:

• parentNodes(node) takes a DOM node, and returns an iterator that yields the node and then each parentNode, unless the current node is a float element's container div, then its corresponding anchor DOM node will be yielded next instead. This is useful when you are listening to events from the entire page and need to determine whether an event's target is logically contained by a React component that has children that use FloatAnchor.

The FloatAnchor component has a reposition method, which you should call if you change the size of the contents of the anchor or float elements.

The FloatAnchor component has a portal property, which is the currently-mounted float element if present. This is exposed mainly for tests. If you find yourself wanting to use it in other contexts, try just putting a ref on the float element!

The container div of the float element has its rfaAnchor property set to be equal to the anchor DOM element.

Related

If you want interactive dropdown menus, check out the react-menu-list module that is built with this!

Types

Flow type declarations for this module are included! As of Flow v0.22, you must add the following entries to your .flowconfig file's options section for them to work:

[options]
esproposal.class_static_fields=enable
esproposal.class_instance_fields=enable