visibilityState

Summary

Returns the visibility state of a webpage.

Property of dom/Documentdom/Document

Syntax

Note: This property is read-only.

var visibilityState = document.visibilityState;

Return Value

Returns an object of type StringString

The current visibility state of the document, one of "hidden", "visible", "prerender", "unloaded".

Examples

var timer = 0;
var PERIOD_VISIBLE = 1000;
var PERIOD_NOT_VISIBLE = 60000;

function onLoad() {
   timer = setInterval(checkEmail, (document.hidden) ? PERIOD_NOT_VISIBLE : PERIOD_VISIBLE);
   if(document.addEventListener) document.addEventListener("visibilitychange", visibilityChanged);
}

function visibilityChanged() {
   clearTimeout(timer);
   timer = setInterval(checkEmail, (document.hidden) ? PERIOD_NOT_VISIBLE : PERIOD_VISIBLE);
}

function checkEmail() {
   // Check server for new messages
}

window.onload = onLoad;

Notes

Use the visibilitychange property to track changes to the visibility state.

Related specifications

Page Visibility

Recommendation

See also

Related articles

Performance

• navigation timing

• resource timing

• user timing

• hidden

• visibilityState

• visibilitychange

• HTML5 Techniques for Optimizing Mobile Performance

Related pages

• hiddenhidden
• visibilitychangevisibilitychange

Attributions

• Microsoft Developer Network: [Windows Internet Explorer API reference Article]