src/offset.js

   1 if ( "getBoundingClientRect" in document.documentElement ) {
   2         jQuery.fn.offset = function( options ) {
   3                 var elem = this[0];
   4
   5                 if ( !elem || !elem.ownerDocument ) {
   6                         return null;
   7                 }
   8
   9                 if ( options ) {
  10                         return this.each(function( i ) {
  11                                 jQuery.offset.setOffset( this, options, i );
  12                         });
  13                 }
  14
  15                 if ( elem === elem.ownerDocument.body ) {
  16                         return jQuery.offset.bodyOffset( elem );
  17                 }
  18
  19                 var box = elem.getBoundingClientRect(), doc = elem.ownerDocument, body = doc.body, docElem = doc.documentElement,
  20                         clientTop = docElem.clientTop || body.clientTop || 0, clientLeft = docElem.clientLeft || body.clientLeft || 0,
  21                         top  = box.top  + (self.pageYOffset || jQuery.support.boxModel && docElem.scrollTop  || body.scrollTop ) - clientTop,
  22                         left = box.left + (self.pageXOffset || jQuery.support.boxModel && docElem.scrollLeft || body.scrollLeft) - clientLeft;
  23
  24                 return { top: top, left: left };
  25         };
  26
  27 } else {
  28         jQuery.fn.offset = function( options ) {
  29                 var elem = this[0];
  30
  31                 if ( !elem || !elem.ownerDocument ) {
  32                         return null;
  33                 }
  34
  35                 if ( options ) {
  36                         return this.each(function( i ) {
  37                                 jQuery.offset.setOffset( this, options, i );
  38                         });
  39                 }
  40
  41                 if ( elem === elem.ownerDocument.body ) {
  42                         return jQuery.offset.bodyOffset( elem );
  43                 }
  44
  45                 jQuery.offset.initialize();
  46
  47                 var offsetParent = elem.offsetParent, prevOffsetParent = elem,
  48                         doc = elem.ownerDocument, computedStyle, docElem = doc.documentElement,
  49                         body = doc.body, defaultView = doc.defaultView,
  50                         prevComputedStyle = defaultView ? defaultView.getComputedStyle( elem, null ) : elem.currentStyle,
  51                         top = elem.offsetTop, left = elem.offsetLeft;
  52
  53                 while ( (elem = elem.parentNode) && elem !== body && elem !== docElem ) {
  54                         if ( jQuery.offset.supportsFixedPosition && prevComputedStyle.position === "fixed" ) {
  55                                 break;
  56                         }
  57
  58                         computedStyle = defaultView ? defaultView.getComputedStyle(elem, null) : elem.currentStyle;
  59                         top  -= elem.scrollTop;
  60                         left -= elem.scrollLeft;
  61
  62                         if ( elem === offsetParent ) {
  63                                 top  += elem.offsetTop;
  64                                 left += elem.offsetLeft;
  65
  66                                 if ( jQuery.offset.doesNotAddBorder && !(jQuery.offset.doesAddBorderForTableAndCells && /^t(able|d|h)$/i.test(elem.nodeName)) ) {
  67                                         top  += parseFloat( computedStyle.borderTopWidth  ) || 0;
  68                                         left += parseFloat( computedStyle.borderLeftWidth ) || 0;
  69                                 }
  70
  71                                 prevOffsetParent = offsetParent, offsetParent = elem.offsetParent;
  72                         }
  73
  74                         if ( jQuery.offset.subtractsBorderForOverflowNotVisible && computedStyle.overflow !== "visible" ) {
  75                                 top  += parseFloat( computedStyle.borderTopWidth  ) || 0;
  76                                 left += parseFloat( computedStyle.borderLeftWidth ) || 0;
  77                         }
  78
  79                         prevComputedStyle = computedStyle;
  80                 }
  81
  82                 if ( prevComputedStyle.position === "relative" || prevComputedStyle.position === "static" ) {
  83                         top  += body.offsetTop;
  84                         left += body.offsetLeft;
  85                 }
  86
  87                 if ( jQuery.offset.supportsFixedPosition && prevComputedStyle.position === "fixed" ) {
  88                         top  += Math.max( docElem.scrollTop, body.scrollTop );
  89                         left += Math.max( docElem.scrollLeft, body.scrollLeft );
  90                 }
  91
  92                 return { top: top, left: left };
  93         };
  94 }
  95
  96 jQuery.offset = {
  97         initialize: function() {
  98                 var body = document.body, container = document.createElement("div"), innerDiv, checkDiv, table, td, bodyMarginTop = parseFloat( jQuery.curCSS(body, "marginTop", true) ) || 0,
  99                         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>";
 100
 101                 jQuery.extend( container.style, { position: "absolute", top: 0, left: 0, margin: 0, border: 0, width: "1px", height: "1px", visibility: "hidden" } );
 102
 103                 container.innerHTML = html;
 104                 body.insertBefore( container, body.firstChild );
 105                 innerDiv = container.firstChild;
 106                 checkDiv = innerDiv.firstChild;
 107                 td = innerDiv.nextSibling.firstChild.firstChild;
 108
 109                 this.doesNotAddBorder = (checkDiv.offsetTop !== 5);
 110                 this.doesAddBorderForTableAndCells = (td.offsetTop === 5);
 111
 112                 checkDiv.style.position = "fixed", checkDiv.style.top = "20px";
 113                 // safari subtracts parent border width here which is 5px
 114                 this.supportsFixedPosition = (checkDiv.offsetTop === 20 || checkDiv.offsetTop === 15);
 115                 checkDiv.style.position = checkDiv.style.top = "";
 116
 117                 innerDiv.style.overflow = "hidden", innerDiv.style.position = "relative";
 118                 this.subtractsBorderForOverflowNotVisible = (checkDiv.offsetTop === -5);
 119
 120                 this.doesNotIncludeMarginInBodyOffset = (body.offsetTop !== bodyMarginTop);
 121
 122                 body.removeChild( container );
 123                 body = container = innerDiv = checkDiv = table = td = null;
 124                 jQuery.offset.initialize = jQuery.noop;
 125         },
 126
 127         bodyOffset: function( body ) {
 128                 var top = body.offsetTop, left = body.offsetLeft;
 129
 130                 jQuery.offset.initialize();
 131
 132                 if ( jQuery.offset.doesNotIncludeMarginInBodyOffset ) {
 133                         top  += parseFloat( jQuery.curCSS(body, "marginTop",  true) ) || 0;
 134                         left += parseFloat( jQuery.curCSS(body, "marginLeft", true) ) || 0;
 135                 }
 136
 137                 return { top: top, left: left };
 138         },
 139
 140         setOffset: function( elem, options, i ) {
 141                 // set position first, in-case top/left are set even on static elem
 142                 if ( /static/.test( jQuery.curCSS( elem, "position" ) ) ) {
 143                         elem.style.position = "relative";
 144                 }
 145                 var curElem   = jQuery( elem ),
 146                         curOffset = curElem.offset(),
 147                         curTop    = parseInt( jQuery.curCSS( elem, "top",  true ), 10 ) || 0,
 148                         curLeft   = parseInt( jQuery.curCSS( elem, "left", true ), 10 ) || 0;
 149
 150                 if ( jQuery.isFunction( options ) ) {
 151                         options = options.call( elem, i, curOffset );
 152                 }
 153
 154                 var props = {
 155                         top:  (options.top  - curOffset.top)  + curTop,
 156                         left: (options.left - curOffset.left) + curLeft
 157                 };
 158
 159                 if ( "using" in options ) {
 160                         options.using.call( elem, props );
 161                 } else {
 162                         curElem.css( props );
 163                 }
 164         }
 165 };
 166
 167
 168 jQuery.fn.extend({
 169         position: function() {
 170                 if ( !this[0] ) {
 171                         return null;
 172                 }
 173
 174                 var elem = this[0],
 175
 176                 // Get *real* offsetParent
 177                 offsetParent = this.offsetParent(),
 178
 179                 // Get correct offsets
 180                 offset       = this.offset(),
 181                 parentOffset = /^body|html$/i.test(offsetParent[0].nodeName) ? { top: 0, left: 0 } : offsetParent.offset();
 182
 183                 // Subtract element margins
 184                 // note: when an element has margin: auto the offsetLeft and marginLeft
 185                 // are the same in Safari causing offset.left to incorrectly be 0
 186                 offset.top  -= parseFloat( jQuery.curCSS(elem, "marginTop",  true) ) || 0;
 187                 offset.left -= parseFloat( jQuery.curCSS(elem, "marginLeft", true) ) || 0;
 188
 189                 // Add offsetParent borders
 190                 parentOffset.top  += parseFloat( jQuery.curCSS(offsetParent[0], "borderTopWidth",  true) ) || 0;
 191                 parentOffset.left += parseFloat( jQuery.curCSS(offsetParent[0], "borderLeftWidth", true) ) || 0;
 192
 193                 // Subtract the two offsets
 194                 return {
 195                         top:  offset.top  - parentOffset.top,
 196                         left: offset.left - parentOffset.left
 197                 };
 198         },
 199
 200         offsetParent: function() {
 201                 return this.map(function() {
 202                         var offsetParent = this.offsetParent || document.body;
 203                         while ( offsetParent && (!/^body|html$/i.test(offsetParent.nodeName) && jQuery.css(offsetParent, "position") === "static") ) {
 204                                 offsetParent = offsetParent.offsetParent;
 205                         }
 206                         return offsetParent;
 207                 });
 208         }
 209 });
 210
 211
 212 // Create scrollLeft and scrollTop methods
 213 jQuery.each( ["Left", "Top"], function( i, name ) {
 214         var method = "scroll" + name;
 215
 216         jQuery.fn[ method ] = function(val) {
 217                 var elem = this[0], win;
 218
 219                 if ( !elem ) {
 220                         return null;
 221                 }
 222
 223                 if ( val !== undefined ) {
 224                         // Set the scroll offset
 225                         return this.each(function() {
 226                                 win = getWindow( this );
 227
 228                                 if ( win ) {
 229                                         win.scrollTo(
 230                                                 !i ? val : jQuery(win).scrollLeft(),
 231                                                  i ? val : jQuery(win).scrollTop()
 232                                         );
 233
 234                                 } else {
 235                                         this[ method ] = val;
 236                                 }
 237                         });
 238                 } else {
 239                         win = getWindow( elem );
 240
 241                         // Return the scroll offset
 242                         return win ? ("pageXOffset" in win) ? win[ i ? "pageYOffset" : "pageXOffset" ] :
 243                                 jQuery.support.boxModel && win.document.documentElement[ method ] ||
 244                                         win.document.body[ method ] :
 245                                 elem[ method ];
 246                 }
 247         };
 248 });
 249
 250 function getWindow( elem ) {
 251         return ("scrollTo" in elem && elem.document) ?
 252                 elem :
 253                 elem.nodeType === 9 ?
 254                         elem.defaultView || elem.parentWindow :
 255                         false;
 256 }