14-offset.js | |
|---|---|
| jQuery Annotated Source. | |
Offset | var rtable = /^t(?:able|d|h)$/i,
rroot = /^(?:body|html)$/i;
if ( "getBoundingClientRect" in document.documentElement ) {
jQuery.fn.offset = function( options ) {
var elem = this[0], box;
if ( options ) {
return this.each(function( i ) {
jQuery.offset.setOffset( this, options, i );
});
}
if ( !elem || !elem.ownerDocument ) {
return null;
}
if ( elem === elem.ownerDocument.body ) {
return jQuery.offset.bodyOffset( elem );
}
try {
box = elem.getBoundingClientRect();
} catch(e) {}
var doc = elem.ownerDocument,
docElem = doc.documentElement; |
| Make sure we're not dealing with a disconnected DOM node | if ( !box || !jQuery.contains( docElem, elem ) ) {
return box ? { top: box.top, left: box.left } : { top: 0, left: 0 };
}
var body = doc.body,
win = getWindow(doc),
clientTop = docElem.clientTop || body.clientTop || 0,
clientLeft = docElem.clientLeft || body.clientLeft || 0,
scrollTop = win.pageYOffset || jQuery.support.boxModel && docElem.scrollTop || body.scrollTop,
scrollLeft = win.pageXOffset || jQuery.support.boxModel && docElem.scrollLeft || body.scrollLeft,
top = box.top + scrollTop - clientTop,
left = box.left + scrollLeft - clientLeft;
return { top: top, left: left };
};
} else {
jQuery.fn.offset = function( options ) {
var elem = this[0];
if ( options ) {
return this.each(function( i ) {
jQuery.offset.setOffset( this, options, i );
});
}
if ( !elem || !elem.ownerDocument ) {
return null;
}
if ( elem === elem.ownerDocument.body ) {
return jQuery.offset.bodyOffset( elem );
}
jQuery.offset.initialize();
var computedStyle,
offsetParent = elem.offsetParent,
prevOffsetParent = elem,
doc = elem.ownerDocument,
docElem = doc.documentElement,
body = doc.body,
defaultView = doc.defaultView,
prevComputedStyle = defaultView ? defaultView.getComputedStyle( elem, null ) : elem.currentStyle,
top = elem.offsetTop,
left = elem.offsetLeft;
while ( (elem = elem.parentNode) && elem !== body && elem !== docElem ) {
if ( jQuery.offset.supportsFixedPosition && prevComputedStyle.position === "fixed" ) {
break;
}
computedStyle = defaultView ? defaultView.getComputedStyle(elem, null) : elem.currentStyle;
top -= elem.scrollTop;
left -= elem.scrollLeft;
if ( elem === offsetParent ) {
top += elem.offsetTop;
left += elem.offsetLeft;
if ( jQuery.offset.doesNotAddBorder && !(jQuery.offset.doesAddBorderForTableAndCells && rtable.test(elem.nodeName)) ) {
top += parseFloat( computedStyle.borderTopWidth ) || 0;
left += parseFloat( computedStyle.borderLeftWidth ) || 0;
}
prevOffsetParent = offsetParent;
offsetParent = elem.offsetParent;
}
if ( jQuery.offset.subtractsBorderForOverflowNotVisible && computedStyle.overflow !== "visible" ) {
top += parseFloat( computedStyle.borderTopWidth ) || 0;
left += parseFloat( computedStyle.borderLeftWidth ) || 0;
}
prevComputedStyle = computedStyle;
}
if ( prevComputedStyle.position === "relative" || prevComputedStyle.position === "static" ) {
top += body.offsetTop;
left += body.offsetLeft;
}
if ( jQuery.offset.supportsFixedPosition && prevComputedStyle.position === "fixed" ) {
top += Math.max( docElem.scrollTop, body.scrollTop );
left += Math.max( docElem.scrollLeft, body.scrollLeft );
}
return { top: top, left: left };
};
}
jQuery.offset = {
initialize: function() {
var body = document.body, container = document.createElement("div"), innerDiv, checkDiv, table, td, bodyMarginTop = parseFloat( jQuery.css(body, "marginTop") ) || 0,
html = "<div style='position:absolute;top:0;left:0;margin:0;border:5px solid #000;padding:0;width:1px;height:1px;'><div></div></div><table style='position:absolute;top:0;left:0;margin:0;border:5px solid #000;padding:0;width:1px;height:1px;' cellpadding='0' cellspacing='0'><tr><td></td></tr></table>";
jQuery.extend( container.style, { position: "absolute", top: 0, left: 0, margin: 0, border: 0, width: "1px", height: "1px", visibility: "hidden" } );
container.innerHTML = html;
body.insertBefore( container, body.firstChild );
innerDiv = container.firstChild;
checkDiv = innerDiv.firstChild;
td = innerDiv.nextSibling.firstChild.firstChild;
this.doesNotAddBorder = (checkDiv.offsetTop !== 5);
this.doesAddBorderForTableAndCells = (td.offsetTop === 5);
checkDiv.style.position = "fixed";
checkDiv.style.top = "20px"; |
| safari subtracts parent border width here which is 5px | this.supportsFixedPosition = (checkDiv.offsetTop === 20 || checkDiv.offsetTop === 15);
checkDiv.style.position = checkDiv.style.top = "";
innerDiv.style.overflow = "hidden";
innerDiv.style.position = "relative";
this.subtractsBorderForOverflowNotVisible = (checkDiv.offsetTop === -5);
this.doesNotIncludeMarginInBodyOffset = (body.offsetTop !== bodyMarginTop);
body.removeChild( container );
jQuery.offset.initialize = jQuery.noop;
},
bodyOffset: function( body ) {
var top = body.offsetTop,
left = body.offsetLeft;
jQuery.offset.initialize();
if ( jQuery.offset.doesNotIncludeMarginInBodyOffset ) {
top += parseFloat( jQuery.css(body, "marginTop") ) || 0;
left += parseFloat( jQuery.css(body, "marginLeft") ) || 0;
}
return { top: top, left: left };
},
setOffset: function( elem, options, i ) {
var position = jQuery.css( elem, "position" ); |
| set position first, in-case top/left are set even on static elem | if ( position === "static" ) {
elem.style.position = "relative";
}
var curElem = jQuery( elem ),
curOffset = curElem.offset(),
curCSSTop = jQuery.css( elem, "top" ),
curCSSLeft = jQuery.css( elem, "left" ),
calculatePosition = (position === "absolute" || position === "fixed") && jQuery.inArray("auto", [curCSSTop, curCSSLeft]) > -1,
props = {}, curPosition = {}, curTop, curLeft; |
| need to be able to calculate position if either top or left is auto and position is either absolute or fixed | if ( calculatePosition ) {
curPosition = curElem.position();
curTop = curPosition.top;
curLeft = curPosition.left;
} else {
curTop = parseFloat( curCSSTop ) || 0;
curLeft = parseFloat( curCSSLeft ) || 0;
}
if ( jQuery.isFunction( options ) ) {
options = options.call( elem, i, curOffset );
}
if (options.top != null) {
props.top = (options.top - curOffset.top) + curTop;
}
if (options.left != null) {
props.left = (options.left - curOffset.left) + curLeft;
}
if ( "using" in options ) {
options.using.call( elem, props );
} else {
curElem.css( props );
}
}
};
jQuery.fn.extend({
position: function() {
if ( !this[0] ) {
return null;
}
var elem = this[0], |
| Get real offsetParent | offsetParent = this.offsetParent(), |
| Get correct offsets | offset = this.offset(),
parentOffset = rroot.test(offsetParent[0].nodeName) ? { top: 0, left: 0 } : offsetParent.offset(); |
| Subtract element margins note: when an element has margin: auto the offsetLeft and marginLeft are the same in Safari causing offset.left to incorrectly be 0 | offset.top -= parseFloat( jQuery.css(elem, "marginTop") ) || 0;
offset.left -= parseFloat( jQuery.css(elem, "marginLeft") ) || 0; |
| Add offsetParent borders | parentOffset.top += parseFloat( jQuery.css(offsetParent[0], "borderTopWidth") ) || 0;
parentOffset.left += parseFloat( jQuery.css(offsetParent[0], "borderLeftWidth") ) || 0; |
| Subtract the two offsets | return {
top: offset.top - parentOffset.top,
left: offset.left - parentOffset.left
};
},
offsetParent: function() {
return this.map(function() {
var offsetParent = this.offsetParent || document.body;
while ( offsetParent && (!rroot.test(offsetParent.nodeName) && jQuery.css(offsetParent, "position") === "static") ) {
offsetParent = offsetParent.offsetParent;
}
return offsetParent;
});
}
}); |
| Create scrollLeft and scrollTop methods | jQuery.each( ["Left", "Top"], function( i, name ) {
var method = "scroll" + name;
jQuery.fn[ method ] = function( val ) {
var elem, win;
if ( val === undefined ) {
elem = this[ 0 ];
if ( !elem ) {
return null;
}
win = getWindow( elem ); |
| Return the scroll offset | return win ? ("pageXOffset" in win) ? win[ i ? "pageYOffset" : "pageXOffset" ] :
jQuery.support.boxModel && win.document.documentElement[ method ] ||
win.document.body[ method ] :
elem[ method ];
} |
| Set the scroll offset | return this.each(function() {
win = getWindow( this );
if ( win ) {
win.scrollTo(
!i ? val : jQuery( win ).scrollLeft(),
i ? val : jQuery( win ).scrollTop()
);
} else {
this[ method ] = val;
}
});
};
});
function getWindow( elem ) {
return jQuery.isWindow( elem ) ?
elem :
elem.nodeType === 9 ?
elem.defaultView || elem.parentWindow :
false;
}
|