README.md

ScrollPagination

React component for handing infinite scroll without infinitely growing the DOM.

Usage

var Page = ScrollPagination.Page;
var manager = new ScrollPagination.Manager();

/** @jsx React.DOM */
<ScrollPagination
	manager={ manager }
	hasPrevPage={ Boolean() }
	hasNextPage={ Boolean() }
	loadPrevPage={ function(){} }
	loadNextPage={ function(){} }
	unloadPage={ function (pageId) {} }>

	<Page id="page-1" manager={ manager }>
		<h1>Render first page of content here</h1>
	</Page>

	<Page id="page-2" manager={ manager }>
		<h1>Render second page of content here</h1>
	</Page>
</ScrollPagination>

var Page = ScrollPagination.Page;
var manager = new ScrollPagination.Manager();

React.createElement(ScrollPagination, {
	manager: manager,
	hasPrevPage: Boolean(),
	hasNextPage: Boolean(),
	loadPrevPage: function(){},
	loadNextPage: function(){},
},
	React.createElement(Page, {
		id: "page-1",
		manager: manager },
			React.createElement('h1', null, "Render first page of content here")),
	React.createElement(Page, {
		id: "page-2",
		manager: manager },
			React.createElement('h1', null, "Render second page of content here")))

ScrollPagination:

• manager must be an instance of ScrollPagination.Manager.

• hasPrevPage must be a boolean indicating if loadPrevPage should be called.

• hasNextPage must be a boolean indicating if loadNextPage should be called.

• loadPrevPage must be a function that causes a re-render with a single page prepended.

• loadNextPage must be a function that causes a re-render with a single page appended.

• unloadPage must be a function that causes a re-render with the specified page id removed.

ScrollPagination.Page:

• manager must be an instance of ScrollPagination.Manager and the same one passed to the ScrollPagination component.

• id must be the id of the page (used for unloadPage).

• component must be a component, defaults to React.DOM.li.

What it does

The scroll container will be determined when the component is first mounted (any parent element with overflow:auto or overflow:scroll, defaults to window).

loadPrevPage and loadNextPage are called when there is one thrid or less of the current page height out of view above and below respectively.

unloadPage is called before loadPrevPage or loadNextPage if there is a page at the opposite end of the visible area entirely out of view.

Each page calculates it's own height and reports it to the ScrollPagination instance via the ScrollPagination.Manager. The ScrollPagination instance keeps track of what pages are added or removed from the top and adjusts the scroll position.

Why

Infinite scroll implementations where DOM nodes are continually added without cleaning up cause the DOM to get very slow the farther you scroll down (especially when you have any kind of dynamic content). Removing what you don't need from the DOM allows scrolling through pages without slowing down the DOM.

How you can help

File an issue if you find anything isn't working as expected.

Pull requests are always welcome, but you should open an issue before working on a new feature (both to ensure it's within the scope of this project and that it's not already being worked on).