Subversion Repositories SmartDukaan

/*
 * File:        FixedHeader.js
 * Version:     2.0.4
 * Description: "Fix" a header at the top of the table, so it scrolls with the table
 * Author:      Allan Jardine (www.sprymedia.co.uk)
 * Created:     Wed 16 Sep 2009 19:46:30 BST
 * Language:    Javascript
 * License:     LGPL
 * Project:     Just a little bit of fun - enjoy :-)
 * Contact:     www.sprymedia.co.uk/contact
 * 
 * Copyright 2009-2010 Allan Jardine, all rights reserved.
 */

/*
 * Function: FixedHeader
 * Purpose:  Provide 'fixed' header, footer and columns on an HTML table
 * Returns:  object:FixedHeader - must be called with 'new'
 * Inputs:   mixed:mTable - target table
 *                                         1. DataTable object - when using FixedHeader with DataTables, or
 *                                         2. HTML table node - when using FixedHeader without DataTables
 *           object:oInit - initialisation settings, with the following properties (each optional)
 *             bool:top -    fix the header (default true)
 *             bool:bottom - fix the footer (default false)
 *             bool:left -   fix the left most column (default false)
 *             bool:right -  fix the right most column (default false)
 *             int:zTop -    fixed header zIndex
 *             int:zBottom - fixed footer zIndex
 *             int:zLeft -   fixed left zIndex
 *             int:zRight -  fixed right zIndex
 */
var FixedHeader = function ( mTable, oInit ) {
        /* Sanity check - you just know it will happen */
        if ( typeof this.fnInit != 'function' )
        {
                alert( "FixedHeader warning: FixedHeader must be initialised with the 'new' keyword." );
                return;
        }
        
        var that = this;
        var oSettings = {
                "aoCache": [],
                "oSides": {
                        "top": true,
                        "bottom": false,
                        "left": false,
                        "right": false
                },
                "oZIndexes": {
                        "top": 104,
                        "bottom": 103,
                        "left": 102,
                        "right": 101
                },
                "oMes": {
                        "iTableWidth": 0,
                        "iTableHeight": 0,
                        "iTableLeft": 0,
                        "iTableRight": 0, /* note this is left+width, not actually "right" */
                        "iTableTop": 0,
                        "iTableBottom": 0 /* note this is top+height, not actually "bottom" */
                },
                "nTable": null,
                "bUseAbsPos": false,
                "bFooter": false
        };
        
        /*
         * Function: fnGetSettings
         * Purpose:  Get the settings for this object
         * Returns:  object: - settings object
         * Inputs:   -
         */
        this.fnGetSettings = function () {
                return oSettings;
        };
        
        /*
         * Function: fnUpdate
         * Purpose:  Update the positioning and copies of the fixed elements
         * Returns:  -
         * Inputs:   -
         */
        this.fnUpdate = function () {
                this._fnUpdateClones();
                this._fnUpdatePositions();
        };
        
        /* Let's do it */
        this.fnInit( mTable, oInit );
};


/*
 * Variable: FixedHeader
 * Purpose:  Prototype for FixedHeader
 * Scope:    global
 */
FixedHeader.prototype = {
        /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
         * Initialisation
         */
        
        /*
         * Function: fnInit
         * Purpose:  The "constructor"
         * Returns:  -
         * Inputs:   {as FixedHeader function}
         */
        fnInit: function ( oTable, oInit )
        {
                var s = this.fnGetSettings();
                var that = this;
                
                /* Record the user definable settings */
                this.fnInitSettings( s, oInit );
                
                /* DataTables specific stuff */
                if ( typeof oTable.fnSettings == 'function' )
                {
                        if ( typeof oTable.fnVersionCheck == 'functon' &&
                             oTable.fnVersionCheck( '1.6.0' ) !== true )
                        {
                                alert( "FixedHeader 2 required DataTables 1.6.0 or later. "+
                                        "Please upgrade your DataTables installation" );
                                return;
                        }
                        
                        var oDtSettings = oTable.fnSettings();
                        
                        if ( oDtSettings.oScroll.sX != "" || oDtSettings.oScroll.sY != "" )
                        {
                                alert( "FixedHeader 2 is not supported with DataTables' scrolling mode at this time" );
                                return;
                        }
                        
                        s.nTable = oDtSettings.nTable;
                        oDtSettings.aoDrawCallback.push( {
                                "fn": function () {
                                        FixedHeader.fnMeasure();
                                        that._fnUpdateClones.call(that);
                                        that._fnUpdatePositions.call(that);
                                },
                                "sName": "FixedHeader"
                        } );
                }
                else
                {
                        s.nTable = oTable;
                }
                
                s.bFooter = ($('>tfoot', s.nTable).length > 0) ? true : false;
                
                /* "Detect" browsers that don't support absolute positioing - or have bugs */
                s.bUseAbsPos = (jQuery.browser.msie && (jQuery.browser.version=="6.0"||jQuery.browser.version=="7.0"));
                
                /* Add the 'sides' that are fixed */
                if ( s.oSides.top )
                {
                        s.aoCache.push( that._fnCloneTable( "fixedHeader", "FixedHeader_Header", that._fnCloneThead ) );
                }
                if ( s.oSides.bottom )
                {
                        s.aoCache.push( that._fnCloneTable( "fixedFooter", "FixedHeader_Footer", that._fnCloneTfoot ) );
                }
                if ( s.oSides.left )
                {
                        s.aoCache.push( that._fnCloneTable( "fixedLeft", "FixedHeader_Left", that._fnCloneTLeft ) );
                }
                if ( s.oSides.right )
                {
                        s.aoCache.push( that._fnCloneTable( "fixedRight", "FixedHeader_Right", that._fnCloneTRight ) );
                }
                
                /* Event listeners for window movement */
                FixedHeader.afnScroll.push( function () {
                        that._fnUpdatePositions.call(that);
                } );
                
                jQuery(window).resize( function () {
                        FixedHeader.fnMeasure();
                        that._fnUpdateClones.call(that);
                        that._fnUpdatePositions.call(that);
                } );
                
                /* Get things right to start with */
                FixedHeader.fnMeasure();
                that._fnUpdateClones();
                that._fnUpdatePositions();
        },
        
        
        /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
         * Support functions
         */
        
        /*
         * Function: fnInitSettings
         * Purpose:  Take the user's settings and copy them to our local store
         * Returns:  -
         * Inputs:   object:s - the local settings object
         *           object:oInit - the user's settings object
         */
        fnInitSettings: function ( s, oInit )
        {
                if ( typeof oInit != 'undefined' )
                {
                        if ( typeof oInit.top != 'undefined' ) {
                                s.oSides.top = oInit.top;
                        }
                        if ( typeof oInit.bottom != 'undefined' ) {
                                s.oSides.bottom = oInit.bottom;
                        }
                        if ( typeof oInit.left != 'undefined' ) {
                                s.oSides.left = oInit.left;
                        }
                        if ( typeof oInit.right != 'undefined' ) {
                                s.oSides.right = oInit.right;
                        }
                        
                        if ( typeof oInit.zTop != 'undefined' ) {
                                s.oZIndexes.top = oInit.zTop;
                        }
                        if ( typeof oInit.zBottom != 'undefined' ) {
                                s.oZIndexes.bottom = oInit.zBottom;
                        }
                        if ( typeof oInit.zLeft != 'undefined' ) {
                                s.oZIndexes.left = oInit.zLeft;
                        }
                        if ( typeof oInit.zRight != 'undefined' ) {
                                s.oZIndexes.right = oInit.zRight;
                        }
                }
                
                /* Detect browsers which have poor position:fixed support so we can use absolute positions.
                 * This is much slower since the position must be updated for each scroll, but widens
                 * compatibility
                 */
                s.bUseAbsPos = (jQuery.browser.msie && 
                        (jQuery.browser.version=="6.0"||jQuery.browser.version=="7.0"));
        },
        
        /*
         * Function: _fnCloneTable
         * Purpose:  Clone the table node and do basic initialisation
         * Returns:  -
         * Inputs:   -
         */
        _fnCloneTable: function ( sType, sClass, fnClone )
        {
                var s = this.fnGetSettings();
                var nCTable;
                
                /* We know that the table _MUST_ has a DIV wrapped around it, because this is simply how
                 * DataTables works. Therefore, we can set this to be relatively position (if it is not
                 * alreadu absolute, and use this as the base point for the cloned header
                 */
                if ( jQuery(s.nTable.parentNode).css('position') != "absolute" )
                {
                        s.nTable.parentNode.style.position = "relative";
                }
                
                /* Just a shallow clone will do - we only want the table node */
                nCTable = s.nTable.cloneNode( false );
                
                var nDiv = document.createElement( 'div' );
                nDiv.style.position = "absolute";
                nDiv.className += " FixedHeader_Cloned "+sType+" "+sClass;
                
                /* Set the zIndexes */
                if ( sType == "fixedHeader" )
                {
                        nDiv.style.zIndex = s.oZIndexes.top;
                }
                if ( sType == "fixedFooter" )
                {
                        nDiv.style.zIndex = s.oZIndexes.bottom;
                }
                if ( sType == "fixedLeft" )
                {
                        nDiv.style.zIndex = s.oZIndexes.left;
                }
                else if ( sType == "fixedRight" )
                {
                        nDiv.style.zIndex = s.oZIndexes.right;
                }
                
                /* Insert the newly cloned table into the DOM, on top of the "real" header */
                nDiv.appendChild( nCTable );
                document.body.appendChild( nDiv );
                
                return {
                        "nNode": nCTable,
                        "nWrapper": nDiv,
                        "sType": sType,
                        "sPosition": "",
                        "sTop": "",
                        "sLeft": "",
                        "fnClone": fnClone
                };
        },
        
        /*
         * Function: _fnUpdatePositions
         * Purpose:  Get the current positioning of the table in the DOM
         * Returns:  -
         * Inputs:   -
         */
        _fnMeasure: function ()
        {
                var
                        s = this.fnGetSettings(),
                        m = s.oMes,
                        jqTable = jQuery(s.nTable),
                        oOffset = jqTable.offset(),
                        iParentScrollTop = this._fnSumScroll( s.nTable.parentNode, 'scrollTop' ),
                        iParentScrollLeft = this._fnSumScroll( s.nTable.parentNode, 'scrollLeft' );
                
                m.iTableWidth = jqTable.outerWidth();
                m.iTableHeight = jqTable.outerHeight();
                m.iTableLeft = oOffset.left + s.nTable.parentNode.scrollLeft;
                m.iTableTop = oOffset.top + iParentScrollTop;
                m.iTableRight = m.iTableLeft + m.iTableWidth;
                m.iTableRight = FixedHeader.oDoc.iWidth - m.iTableLeft - m.iTableWidth;
                m.iTableBottom = FixedHeader.oDoc.iHeight - m.iTableTop - m.iTableHeight;
        },
        
        /*
         * Function: _fnSumScroll
         * Purpose:  Sum node parameters all the way to the top
         * Returns:  int: sum
         * Inputs:   node:n - node to consider
         *           string:side - scrollTop or scrollLeft
         */
        _fnSumScroll: function ( n, side )
        {
                var i = n[side];
                while ( n = n.parentNode )
                {
                        if ( n.nodeName != 'HTML' && n.nodeName != 'BODY' )
                        {
                                break;
                        }
                        i = n[side];
                }
                return i;
        },
        
        /*
         * Function: _fnUpdatePositions
         * Purpose:  Loop over the fixed elements for this table and update their positions
         * Returns:  -
         * Inputs:   -
         */
        _fnUpdatePositions: function ()
        {
                var s = this.fnGetSettings();
                this._fnMeasure();
                
                for ( var i=0, iLen=s.aoCache.length ; i<iLen ; i++ )
                {
                        if ( s.aoCache[i].sType == "fixedHeader" )
                        {
                                this._fnScrollFixedHeader( s.aoCache[i] );
                        }
                        else if ( s.aoCache[i].sType == "fixedFooter" )
                        {
                                this._fnScrollFixedFooter( s.aoCache[i] );
                        }
                        else if ( s.aoCache[i].sType == "fixedLeft" )
                        {
                                this._fnScrollHorizontalLeft( s.aoCache[i] );
                        }
                        else
                        {
                                this._fnScrollHorizontalRight( s.aoCache[i] );
                        }
                }
        },
        
        /*
         * Function: _fnUpdateClones
         * Purpose:  Loop over the fixed elements for this table and call their cloning functions
         * Returns:  -
         * Inputs:   -
         */
        _fnUpdateClones: function ()
        {
                var s = this.fnGetSettings();
                for ( var i=0, iLen=s.aoCache.length ; i<iLen ; i++ )
                {
                        s.aoCache[i].fnClone.call( this, s.aoCache[i] );
                }
        },
        
        
        /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
         * Scrolling functions
         */
        
        /*
         * Function: _fnScrollHorizontalLeft
         * Purpose:  Update the positioning of the scrolling elements
         * Returns:  -
         * Inputs:   object:oCache - the cahced values for this fixed element
         */
        _fnScrollHorizontalRight: function ( oCache )
        {
                var
                        s = this.fnGetSettings(),
                        oMes = s.oMes,
                        oWin = FixedHeader.oWin,
                        oDoc = FixedHeader.oDoc,
                        nTable = oCache.nWrapper,
                        iFixedWidth = jQuery(nTable).outerWidth();
                
                if ( oWin.iScrollRight < oMes.iTableRight )
                {
                        /* Fully right aligned */
                        this._fnUpdateCache( oCache, 'sPosition', 'absolute', 'position', nTable.style );
                        this._fnUpdateCache( oCache, 'sTop', oMes.iTableTop+"px", 'top', nTable.style );
                        this._fnUpdateCache( oCache, 'sLeft', (oMes.iTableLeft+oMes.iTableWidth-iFixedWidth)+"px", 'left', nTable.style );      
                }
                else if ( oMes.iTableLeft < oDoc.iWidth-oWin.iScrollRight-iFixedWidth )
                {
                        /* Middle */
                        if ( s.bUseAbsPos )
                        {
                                this._fnUpdateCache( oCache, 'sPosition', 'absolute', 'position', nTable.style );
                                this._fnUpdateCache( oCache, 'sTop', oMes.iTableTop+"px", 'top', nTable.style );
                                this._fnUpdateCache( oCache, 'sLeft', (oDoc.iWidth-oWin.iScrollRight-iFixedWidth)+"px", 'left', nTable.style );
                        }
                        else
                        {
                                this._fnUpdateCache( oCache, 'sPosition', 'fixed', 'position', nTable.style );
                                this._fnUpdateCache( oCache, 'sTop', (oMes.iTableTop-oWin.iScrollTop)+"px", 'top', nTable.style );
                                this._fnUpdateCache( oCache, 'sLeft', (oWin.iWidth-iFixedWidth)+"px", 'left', nTable.style );
                        }       
                }
                else
                {
                        /* Fully left aligned */
                        this._fnUpdateCache( oCache, 'sPosition', 'absolute', 'position', nTable.style );
                        this._fnUpdateCache( oCache, 'sTop', oMes.iTableTop+"px", 'top', nTable.style );
                        this._fnUpdateCache( oCache, 'sLeft', oMes.iTableLeft+"px", 'left', nTable.style );     
                }
        },
        
        /*
         * Function: _fnScrollHorizontalLeft
         * Purpose:  Update the positioning of the scrolling elements
         * Returns:  -
         * Inputs:   object:oCache - the cahced values for this fixed element
         */
        _fnScrollHorizontalLeft: function ( oCache )
        {
                var
                        s = this.fnGetSettings(),
                        oMes = s.oMes,
                        oWin = FixedHeader.oWin,
                        oDoc = FixedHeader.oDoc,
                        nTable = oCache.nWrapper,
                        iCellWidth = jQuery(nTable).outerWidth();
                
                if ( oWin.iScrollLeft < oMes.iTableLeft )
                {
                        /* Fully left align */
                        this._fnUpdateCache( oCache, 'sPosition', 'absolute', 'position', nTable.style );
                        this._fnUpdateCache( oCache, 'sTop', oMes.iTableTop+"px", 'top', nTable.style );
                        this._fnUpdateCache( oCache, 'sLeft', oMes.iTableLeft+"px", 'left', nTable.style );     
                }
                else if ( oWin.iScrollLeft < oMes.iTableLeft+oMes.iTableWidth-iCellWidth )
                {
                        /* Middle */
                        if ( s.bUseAbsPos )
                        {
                                this._fnUpdateCache( oCache, 'sPosition', 'absolute', 'position', nTable.style );
                                this._fnUpdateCache( oCache, 'sTop', oMes.iTableTop+"px", 'top', nTable.style );
                                this._fnUpdateCache( oCache, 'sLeft', oWin.iScrollLeft+"px", 'left', nTable.style );
                        }
                        else
                        {
                                this._fnUpdateCache( oCache, 'sPosition', 'fixed', 'position', nTable.style );
                                this._fnUpdateCache( oCache, 'sTop', (oMes.iTableTop-oWin.iScrollTop)+"px", 'top', nTable.style );
                                this._fnUpdateCache( oCache, 'sLeft', "0px", 'left', nTable.style );
                        }       
                }
                else
                {
                        /* Fully right align */
                        this._fnUpdateCache( oCache, 'sPosition', 'absolute', 'position', nTable.style );
                        this._fnUpdateCache( oCache, 'sTop', oMes.iTableTop+"px", 'top', nTable.style );
                        this._fnUpdateCache( oCache, 'sLeft', (oMes.iTableLeft+oMes.iTableWidth-iCellWidth)+"px", 'left', nTable.style );       
                }
        },
        
        /*
         * Function: _fnScrollFixedFooter
         * Purpose:  Update the positioning of the scrolling elements
         * Returns:  -
         * Inputs:   object:oCache - the cahced values for this fixed element
         */
        _fnScrollFixedFooter: function ( oCache )
        {
                var
                        s = this.fnGetSettings(),
                        oMes = s.oMes,
                        oWin = FixedHeader.oWin,
                        oDoc = FixedHeader.oDoc,
                        nTable = oCache.nWrapper,
                        iTheadHeight = jQuery("thead", s.nTable).outerHeight(),
                        iCellHeight = jQuery(nTable).outerHeight();
                
                if ( oWin.iScrollBottom < oMes.iTableBottom )
                {
                        /* Below */
                        this._fnUpdateCache( oCache, 'sPosition', 'absolute', 'position', nTable.style );
                        this._fnUpdateCache( oCache, 'sTop', (oMes.iTableTop+oMes.iTableHeight-iCellHeight)+"px", 'top', nTable.style );
                        this._fnUpdateCache( oCache, 'sLeft', oMes.iTableLeft+"px", 'left', nTable.style );     
                }
                else if ( oWin.iScrollBottom < oMes.iTableBottom+oMes.iTableHeight-iCellHeight-iTheadHeight )
                {
                        /* Middle */
                        if ( s.bUseAbsPos )
                        {
                                this._fnUpdateCache( oCache, 'sPosition', "absolute", 'position', nTable.style );
                                this._fnUpdateCache( oCache, 'sTop', (oDoc.iHeight-oWin.iScrollBottom-iCellHeight)+"px", 'top', nTable.style );
                                this._fnUpdateCache( oCache, 'sLeft', oMes.iTableLeft+"px", 'left', nTable.style );
                        }
                        else
                        {
                                this._fnUpdateCache( oCache, 'sPosition', 'fixed', 'position', nTable.style );
                                this._fnUpdateCache( oCache, 'sTop', (oWin.iHeight-iCellHeight)+"px", 'top', nTable.style );
                                this._fnUpdateCache( oCache, 'sLeft', (oMes.iTableLeft-oWin.iScrollLeft)+"px", 'left', nTable.style );  
                        }
                }
                else
                {
                        /* Above */
                        this._fnUpdateCache( oCache, 'sPosition', 'absolute', 'position', nTable.style );
                        this._fnUpdateCache( oCache, 'sTop', (oMes.iTableTop+iCellHeight)+"px", 'top', nTable.style );
                        this._fnUpdateCache( oCache, 'sLeft', oMes.iTableLeft+"px", 'left', nTable.style );     
                }
        },
        
        /*
         * Function: _fnScrollFixedHeader
         * Purpose:  Update the positioning of the scrolling elements
         * Returns:  -
         * Inputs:   object:oCache - the cahced values for this fixed element
         */
        _fnScrollFixedHeader: function ( oCache )
        {
                var
                        s = this.fnGetSettings(),
                        oMes = s.oMes,
                        oWin = FixedHeader.oWin,
                        oDoc = FixedHeader.oDoc,
                        nTable = oCache.nWrapper,
                        iTbodyHeight = s.nTable.getElementsByTagName('tbody')[0].offsetHeight;
                
                if ( oMes.iTableTop > oWin.iScrollTop )
                {
                        /* Above the table */
                        this._fnUpdateCache( oCache, 'sPosition', "absolute", 'position', nTable.style );
                        this._fnUpdateCache( oCache, 'sTop', oMes.iTableTop+"px", 'top', nTable.style );
                        this._fnUpdateCache( oCache, 'sLeft', oMes.iTableLeft+"px", 'left', nTable.style );
                }
                else if ( oWin.iScrollTop > oMes.iTableTop+iTbodyHeight )
                {
                        /* At the bottom of the table */
                        this._fnUpdateCache( oCache, 'sPosition', "absolute", 'position', nTable.style );
                        this._fnUpdateCache( oCache, 'sTop', (oMes.iTableTop+iTbodyHeight)+"px", 'top', nTable.style );
                        this._fnUpdateCache( oCache, 'sLeft', oMes.iTableLeft+"px", 'left', nTable.style );
                }
                else
                {
                        /* In the middle of the table */
                        if ( s.bUseAbsPos )
                        {
                                this._fnUpdateCache( oCache, 'sPosition', "absolute", 'position', nTable.style );
                                this._fnUpdateCache( oCache, 'sTop', oWin.iScrollTop+"px", 'top', nTable.style );
                                this._fnUpdateCache( oCache, 'sLeft', oMes.iTableLeft+"px", 'left', nTable.style );
                        }
                        else
                        {
                                this._fnUpdateCache( oCache, 'sPosition', 'fixed', 'position', nTable.style );
                                this._fnUpdateCache( oCache, 'sTop', "0px", 'top', nTable.style );
                                this._fnUpdateCache( oCache, 'sLeft', (oMes.iTableLeft-oWin.iScrollLeft)+"px", 'left', nTable.style );
                        }
                }
        },
        
        /*
         * Function: _fnUpdateCache
         * Purpose:  Check the cache and update cache and value if needed
         * Returns:  -
         * Inputs:   object:oCache - local cache object
         *           string:sCache - cache property
         *           string:sSet - value to set
         *           string:sProperty - object property to set
         *           object:oObj - object to update
         */
        _fnUpdateCache: function ( oCache, sCache, sSet, sProperty, oObj )
        {
                if ( oCache[sCache] != sSet )
                {
                        oObj[sProperty] = sSet;
                        oCache[sCache] = sSet;
                }
        },
        
        
        
        /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
         * Cloning functions
         */
        
        /*
         * Function: _fnCloneThead
         * Purpose:  Clone the thead element
         * Returns:  -
         * Inputs:   object:oCache - the cahced values for this fixed element
         */
        _fnCloneThead: function ( oCache )
        {
                var s = this.fnGetSettings();
                var nTable = oCache.nNode;
                
                /* Set the wrapper width to match that of the cloned table */
                oCache.nWrapper.style.width = jQuery(s.nTable).outerWidth()+"px";
                
                /* Remove any children the cloned table has */
                while ( nTable.childNodes.length > 0 )
                {
                        jQuery('thead th', nTable).unbind( 'click' );
                        nTable.removeChild( nTable.childNodes[0] );
                }
                
                /* Clone the DataTables header */
                var nThead = jQuery('thead', s.nTable).clone(true)[0];
                nTable.appendChild( nThead );
                
                /* Copy the widths across - apparently a clone isn't good enough for this */
                jQuery("thead:eq(0)>tr th", s.nTable).each( function (i) {
                        jQuery("thead:eq(0)>tr th:eq("+i+")", nTable).width( jQuery(this).width() );
                } );
                
                jQuery("thead:eq(0)>tr td", s.nTable).each( function (i) {
                        jQuery("thead:eq(0)>tr th:eq("+i+")", nTable)[0].style.width( jQuery(this).width() );
                } );
        },
        
        /*
         * Function: _fnCloneTfoot
         * Purpose:  Clone the tfoot element
         * Returns:  -
         * Inputs:   object:oCache - the cahced values for this fixed element
         */
        _fnCloneTfoot: function ( oCache )
        {
                var s = this.fnGetSettings();
                var nTable = oCache.nNode;
                
                /* Set the wrapper width to match that of the cloned table */
                oCache.nWrapper.style.width = jQuery(s.nTable).outerWidth()+"px";
                
                /* Remove any children the cloned table has */
                while ( nTable.childNodes.length > 0 )
                {
                        nTable.removeChild( nTable.childNodes[0] );
                }
                
                /* Clone the DataTables footer */
                var nTfoot = jQuery('tfoot', s.nTable).clone(true)[0];
                nTable.appendChild( nTfoot );
                
                /* Copy the widths across - apparently a clone isn't good enough for this */
                jQuery("tfoot:eq(0)>tr th", s.nTable).each( function (i) {
                        jQuery("tfoot:eq(0)>tr th:eq("+i+")", nTable).width( jQuery(this).width() );
                } );
                
                jQuery("tfoot:eq(0)>tr td", s.nTable).each( function (i) {
                        jQuery("tfoot:eq(0)>tr th:eq("+i+")", nTable)[0].style.width( jQuery(this).width() );
                } );
        },
        
        /*
         * Function: _fnCloneTLeft
         * Purpose:  Clone the left column
         * Returns:  -
         * Inputs:   object:oCache - the cahced values for this fixed element
         */
        _fnCloneTLeft: function ( oCache )
        {
                var s = this.fnGetSettings();
                var nTable = oCache.nNode;
                var iCols = jQuery('tbody tr:eq(0) td', s.nTable).length;
                var bRubbishOldIE = ($.browser.msie && ($.browser.version == "6.0" || $.browser.version == "7.0"));
                
                /* Remove any children the cloned table has */
                while ( nTable.childNodes.length > 0 )
                {
                        nTable.removeChild( nTable.childNodes[0] );
                }
                
                /* Is this the most efficient way to do this - it looks horrible... */
                nTable.appendChild( jQuery("thead", s.nTable).clone(true)[0] );
                nTable.appendChild( jQuery("tbody", s.nTable).clone(true)[0] );
                if ( s.bFooter )
                {
                        nTable.appendChild( jQuery("tfoot", s.nTable).clone(true)[0] );
                }
                
                jQuery('thead tr th:gt(0)', nTable).remove();
                jQuery('tfoot tr th:gt(0)', nTable).remove();
                
                /* Basically the same as used in FixedColumns - remove and copy heights */
                $('tbody tr', nTable).each( function (k) {
                        $('td:gt(0)', this).remove();
                        
                        /* Can we use some kind of object detection here?! This is very nasty - damn browsers */
                        if ( $.browser.mozilla || $.browser.opera )
                        {
                                $('td', this).height( $('tbody tr:eq('+k+')', that.dom.body).outerHeight() );
                        }
                        else
                        {
                                $('td', this).height( $('tbody tr:eq('+k+')', that.dom.body).outerHeight() - iBoxHack );
                        }
                        
                        if ( !bRubbishOldIE )
                        {
                                $('tbody tr:eq('+k+')', that.dom.body).height( $('tbody tr:eq('+k+')', that.dom.body).outerHeight() );          
                        }
                } );
                
                var iWidth = jQuery('thead tr th:eq(0)', s.nTable).outerWidth();
                nTable.style.width = iWidth+"px";
                oCache.nWrapper.style.width = iWidth+"px";
        },
        
        /*
         * Function: _fnCloneTRight
         * Purpose:  Clone the right most colun
         * Returns:  -
         * Inputs:   object:oCache - the cahced values for this fixed element
         */
        _fnCloneTRight: function ( oCache )
        {
                var s = this.fnGetSettings();
                var nTable = oCache.nNode;
                var iCols = jQuery('tbody tr:eq(0) td', s.nTable).length;
                var bRubbishOldIE = ($.browser.msie && ($.browser.version == "6.0" || $.browser.version == "7.0"));
                
                /* Remove any children the cloned table has */
                while ( nTable.childNodes.length > 0 )
                {
                        nTable.removeChild( nTable.childNodes[0] );
                }
                
                /* Is this the most efficient way to do this - it looks horrible... */
                nTable.appendChild( jQuery("thead", s.nTable).clone(true)[0] );
                nTable.appendChild( jQuery("tbody", s.nTable).clone(true)[0] );
                if ( s.bFooter )
                {
                        nTable.appendChild( jQuery("tfoot", s.nTable).clone(true)[0] );
                }
                jQuery('thead tr th:not(:nth-child('+iCols+'n))', nTable).remove();
                jQuery('tfoot tr th:not(:nth-child('+iCols+'n))', nTable).remove();
                
                /* Basically the same as used in FixedColumns - remove and copy heights */
                $('tbody tr', nTable).each( function (k) {
                        $('td:lt('+iCols-1+')', this).remove();
                        
                        /* Can we use some kind of object detection here?! This is very nasty - damn browsers */
                        if ( $.browser.mozilla || $.browser.opera )
                        {
                                $('td', this).height( $('tbody tr:eq('+k+')', that.dom.body).outerHeight() );
                        }
                        else
                        {
                                $('td', this).height( $('tbody tr:eq('+k+')', that.dom.body).outerHeight() - iBoxHack );
                        }
                        
                        if ( !bRubbishOldIE )
                        {
                                $('tbody tr:eq('+k+')', that.dom.body).height( $('tbody tr:eq('+k+')', that.dom.body).outerHeight() );          
                        }
                } );
                
                var iWidth = jQuery('thead tr th:eq('+(iCols-1)+')', s.nTable).outerWidth();
                nTable.style.width = iWidth+"px";
                oCache.nWrapper.style.width = iWidth+"px";
        }
};

        
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Static properties and methods
 *   We use these for speed! This information is common to all instances of FixedHeader, so no
 * point if having them calculated and stored for each different instance.
 */

/*
 * Variable: oWin
 * Purpose:  Store information about the window positioning
 * Scope:    FixedHeader
 */
FixedHeader.oWin = {
        "iScrollTop": 0,
        "iScrollRight": 0,
        "iScrollBottom": 0,
        "iScrollLeft": 0,
        "iHeight": 0,
        "iWidth": 0
};

/*
 * Variable: oDoc
 * Purpose:  Store information about the document size
 * Scope:    FixedHeader
 */
FixedHeader.oDoc = {
        "iHeight": 0,
        "iWidth": 0
};

/*
 * Variable: afnScroll
 * Purpose:  Array of functions that are to be used for the scrolling components
 * Scope:    FixedHeader
 */
FixedHeader.afnScroll = [];

/*
 * Function: fnMeasure
 * Purpose:  Update the measurements for the window and document
 * Returns:  -
 * Inputs:   -
 */
FixedHeader.fnMeasure = function ()
{
        var
                jqWin = jQuery(window),
                jqDoc = jQuery(document),
                oWin = FixedHeader.oWin,
                oDoc = FixedHeader.oDoc;
        
        oDoc.iHeight = jqDoc.height();
        oDoc.iWidth = jqDoc.width();
        
        oWin.iHeight = jqWin.height();
        oWin.iWidth = jqWin.width();
        oWin.iScrollTop = jqWin.scrollTop();
        oWin.iScrollLeft = jqWin.scrollLeft();
        oWin.iScrollRight = oDoc.iWidth - oWin.iScrollLeft - oWin.iWidth;
        oWin.iScrollBottom = oDoc.iHeight - oWin.iScrollTop - oWin.iHeight;
};

        
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Global processing
 */

/*
 * Just one 'scroll' event handler in FixedHeader, which calls the required components. This is
 * done as an optimisation, to reduce calculation and proagation time
 */
jQuery(window).scroll( function () {
        FixedHeader.fnMeasure();
        for ( var i=0, iLen=FixedHeader.afnScroll.length ; i<iLen ; i++ )
        {
                FixedHeader.afnScroll[i]();
        }
} );