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The
Document.hasFocus() method returns a Boolean value indicating whether the document or any element inside the document has focus. This method can be used to determine whether the active element in a document has focus.When viewing a document, an element with focus is always the active element in the document, but an active element does not necessarily have focus. For example, an active element within a popup window that is not the foreground does not have focus.
Syntax
focused = document.hasFocus();
Return value
false if the active element in the document has no focus; true if the active element in the document has focus.
Example
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<title>TEST</title>
<style>
#message { font-weight: bold; }
</style>
<script>
setInterval( checkPageFocus, 200 );
function checkPageFocus() {
var info = document.getElementById("message");
if ( document.hasFocus() ) {
info.innerHTML = "The document has the focus.";
} else {
info.innerHTML = "The document doesn't have the focus.";
}
}
function openWindow() {
window.open (
"https://developer.mozilla.org/",
"mozdev",
"width=640,
height=300,
left=150,
top=260"
);
}
</script>
</head>
<body>
<h1>JavaScript hasFocus example</h1>
<div id="message">Waiting for user action</div>
<div><button onclick="openWindow()">Open a new window</button></div>
</body>
</html>
Specification
| Specification | Status | Comment |
|---|---|---|
| WHATWG HTML Living Standard The definition of 'Document.hasFocus()' in that specification. |
Living Standard | Initial definition |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|
| Basic support | 30 | 3.0 (1.9) | 6.0 | 12.10 | (Yes) |
| Feature | Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|
| Basic support | ? | 1.0 (1.9) | ? | No support | ? |