You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
66 lines
2.0 KiB
JavaScript
66 lines
2.0 KiB
JavaScript
10 years ago
|
/*! Fixedfixed: a CSS position:fixed qualifier. (c)2012 @scottjehl, Filament Group, Inc. Dual license: MIT and/or GPLv2 */
|
||
|
|
(function( w, undefined ){
|
||
|
|
|
||
|
|
var htmlclass = "fixed-supported",
|
||
|
|
el = w.document.createElement( "div" ),
|
||
|
|
ua = w.navigator.userAgent,
|
||
|
|
docEl = w.document.documentElement;
|
||
|
|
|
||
|
|
// fix the test element
|
||
|
|
el.style.position = "fixed";
|
||
|
|
el.style.top = 0;
|
||
|
|
|
||
|
|
// support test
|
||
|
|
function checkFixed(){
|
||
|
|
|
||
|
|
var scroll = "scrollTop" in w.document.body ? w.document.body.scrollTop : docEl.scrollTop;
|
||
|
|
|
||
|
|
// only run test if there's a scroll we can compare
|
||
|
|
if( scroll !== undefined && scroll > 0 && w.document.body ){
|
||
|
|
|
||
|
|
w.document.body.insertBefore( el, w.document.body.firstChild );
|
||
|
|
|
||
|
|
if( !el.getBoundingClientRect || el.getBoundingClientRect().top !== 0 ){
|
||
|
|
// Fixed is not working or can't be tested
|
||
|
|
docEl.className = docEl.className.replace( htmlclass, "" );
|
||
|
|
}
|
||
|
|
|
||
|
|
// remove the test element
|
||
|
|
w.document.body.removeChild( el );
|
||
|
|
|
||
|
|
// unbind the handlers
|
||
|
|
if( w.removeEventListener ){
|
||
|
|
w.removeEventListener( "scroll", checkFixed, false );
|
||
|
|
}
|
||
|
|
else{
|
||
|
|
w.detachEvent( "onscroll", checkFixed );
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// if a particular UA is known to return false results with this feature test, try and avoid that UA here.
|
||
|
|
if(
|
||
|
|
// Android 2.1, 2.2, 2.5, and 2.6 Webkit
|
||
|
|
!( ua.match( /Android 2\.[1256]/ ) && ua.indexOf( "AppleWebKit") > -1 ) ||
|
||
|
|
// Opera Mobile less than version 11.0 (7458)
|
||
|
|
!( ua.match( /Opera Mobi\/([0-9]+)/ ) && RegExp.$1 < 7458 ) ||
|
||
|
|
// Opera Mini
|
||
|
|
!( w.operamini && ({}).toString.call( w.operamini ) === "[object OperaMini]" ) ||
|
||
|
|
// Firefox Mobile less than version 6
|
||
|
|
!( ua.match( /Fennec\/([0-9]+)/ ) && RegExp.$1 < 6 )
|
||
|
|
// If necessary, add the other untestable browsers here...
|
||
|
|
){
|
||
|
|
//add the HTML class for now.
|
||
|
|
docEl.className += " " + htmlclass;
|
||
|
|
|
||
|
|
// bind to scroll event so we can test and potentially degrade
|
||
|
|
if( w.addEventListener ){
|
||
|
|
w.addEventListener( "scroll", checkFixed, false );
|
||
|
|
}
|
||
|
|
else{
|
||
|
|
w.attachEvent( "onscroll", checkFixed );
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
w.FixedFixed = checkFixed;
|
||
|
|
}( this ));
|