#FixedHeader_Ext

Extending Data-table FixedHeader Plugin

I faced couple of issues while using data-table fixedHeader plugin. I created this FixedHeader_Ext to extends FixedHeaer plugin functions.

#Issue 1

In FixedHeader plugin below code was called multiple times, while hiding and showing multiple columns using colum(index).visible().

.on('column-visibility.dt', function () {
	FixedHeader.fnMeasure();
	that._fnUpdateClones( true );
	that._fnUpdatePositions();
} );

so I removed this listener after creating datatable-FixedHeader instance like below

fixedHeaderRef = new $.fn.dataTable.FixedHeader($('#example_table'))

/* removed listener which is causing more performance issue */
  if (fixedHeaderRef.fnGetSettings().nTable) {
    $(fixedHeaderRef.fnGetSettings().nTable).off('column-visibility.dt');
  }

added new public method 'reDraw' to draw a Fixed-Header when required. In my case I am calling this method after column modifications.

//exposed these function to redraw when requir
FixedHeader.prototype.reDraw = function(){
	FixedHeader.fnMeasure();
	this._fnUpdateClones( true );
	this._fnUpdatePositions();
}

#Issue 2

getting null pointer exception in method '_fnClassUpdate'.

at some senario param 'dest' become null. it's clearly mentioned that two columns 'source' and 'dest' has identical structure no error checking. but I am getting null pointer exception. so I added null pointer check by extending the method.

It may be issue with my implementation or plugin. Need to check.

/*
 * Copy the classes of all child nodes from one element to another. This implies
 * that the two have identical structure - no error checking is performed to that
 * fact.
 *  @param {element} source Node to copy classes from
 *  @param {element} dest Node to copy classes too
 */


 _fnClassUpdate: function ( source, dest )

#Installation

you need to add the 'dataTables.fixedHeader.ext.js' after 'dataTables.fixedHeader.js' like below

<script src="bower_components/datatables-fixedheader/js/dataTables.fixedHeader.js"></script>
<script src="bower_components/datatables-fixedheader-ext/js/dataTables_fixedHeader_ext.js"></script>