Get a callback when an element enters the viewport (body) or a custom viewport
Know when an element is in the window viewport or a custom viewport.
var inViewport = require'in-viewport';var elem = documentgetElementById'myFancyDiv';var isInViewport = inViewportelem; // returns `true` or `false`alert'myFancyDiv is ' + isInViewport ? 'visible' : 'not visible' + ' in the window';
We watch for your element to enters the viewport and call your callback when it does.
var inViewport = require'in-viewport';var elem = documentgetElementById'myFancyDiv';inViewportelem visible;// elt === elemalerteltid + ' is visible in the window !';
The first callback argument is always the
element that entered the viewport.
By default, we use the current window as the reference viewport. But you can also specify another element as a reference viewport.
var inViewport = require'in-viewport';var customContainer = documentgetElementById'myFancyContainer';var elem = documentgetElementById'myFancyDiv';inViewportelem container: customContainer visible;alert'myfancyDiv is visible in the `customContainer` !';
By default, when your element precisely enters the viewport, you get a callback.
But maybe you want to know when your element is soon-to-be-shown in the viewport?
offset param for that!
var inViewport = require'in-viewport';var elem = documentgetElementById'myFancyDiv';inViewportelem offset: 300 visible;alert'myfancyDiv is visible in the `customContainer` !';
When your element is near
300px of the viewport, you get your callback / true result.
If you are creating elements dynamically, be sure to call
inViewport when the
element is in the DOM.
Otherwise it may fail on old browsers.
We check for newly visible elements on
We use MutationObserver to listen for newly added DOM nodes that were previously registered with in-viewport.
MutationObserver is not compatible with old browsers.
That is why, if you need old browsers full compatibility, you should call in-viewport after inserting elements in the DOM.
- Images, iframes, widgets lazyloader
- infinite scroll
- loading widgets only when needed
Be sure to be in [standards-compliant mode](http://en.wikipedia.org/wiki/HTML5#Markup].
Quirks mode is not supported since most browsers will report invalid values for window viewport.
Launch the dev server:
npm run dev
Browse to http://localhost:8080/__zuul.
We provide a pre-built version of
But you can build your own:
npm run build
You get the build in
Please consider using browserify.
Copyright (c) 2013 Vincent Voyer
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.