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mozbrowserasyncscroll

Obsolete
This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.

Non-standard
This feature is not on a current W3C standards track, but it is supported on the Firefox OS platform. Although implementations may change in the future and it is not supported widely across browsers, it is suitable for use in code dedicated to Firefox OS apps.

The mozbrowserasyncscroll event is fired when the content of a browser <iframe> is scrolled.

General info

Specification
Non standard
Interface
CustomEvent
Bubbles
Yes
Cancelable
Yes
Target
<iframe>
Default Action
None

Properties

Property Type Description
target Read only EventTarget The browser iframe
type Read only DOMString The type of event.
bubbles Read only boolean Does the event normally bubble?
cancelable Read only boolean Is it possible to cancel the event?
details Read only object A custom object

details

The details property returns an anonymous JavaScript object with the following properties:

top
The scroll top position in CSS pixels of the document within the browser <iframe>.
left
The scroll left position in CSS pixels of the document within the browser <iframe>.
width
The width in CSS pixels of the visible part of the document within the browser <iframe>.
height
The height in CSS pixels of the visible part of the document within the browser <iframe>.
scrollWidth
The total content width in CSS pixels of the document within the browser <iframe>.
scrollHeight
The total content height in CSS pixels of the document within the browser <iframe>.

Note: top + height may be larger than scrollHeight. This indicates that the content is over-scrolled, which occurs when the page "rubber-bands" after being scrolled all the way to the bottom. Similarly, left + width may be greater than scrollWidth, and both left and top may be negative.

Note: For performance reasons, this event is asynchronous. That means that the value retrieved through the event object can be different than the real current position of the scroll when the event is processed.

Examples

var browser = document.querySelector("iframe");

browser.addEventListener("mozbrowserasyncscroll", function( event ) {
  console.log("The scroll top position of the document is:" + event.details.top + "px");
});

See also

Document Tags and Contributors

 Contributors to this page: chrisdavidmills, teoli, kscarfone, Jeremie
 Last updated by: chrisdavidmills,