jquery.filtertable.js modification to not reset when clicking on keyword input https://github.com/sglessard/jQuery.FilterTable/blob/master/jquery.filtertable.js

jquery.filtertable.js

/**
 * jquery.filterTable
 *
 * This plugin will add a search filter to tables. When typing in the filter,
 * any rows that do not contain the filter will be hidden.
 *
 * Utilizes bindWithDelay() if available. https://github.com/bgrins/bindWithDelay
 *
 * @version v1.5
 * @author Sunny Walker, swalker@hawaii.edu
 */
(function($) {
	var jversion = $.fn.jquery.split('.'), jmajor = parseFloat(jversion[0]), jminor = parseFloat(jversion[1]);
	if (jmajor<2 && jminor<8) { // build the pseudo selector for jQuery < 1.8
		$.expr[':'].filterTableFind = function(a, i, m) { // build the case insensitive filtering functionality as a pseudo-selector expression
			return $(a).text().toUpperCase().indexOf(m[3].toUpperCase())>=0;
		};
	} else { // build the pseudo selector for jQuery >= 1.8
		$.expr[':'].filterTableFind = jQuery.expr.createPseudo(function(arg) {
			return function(el) {
				return $(el).text().toUpperCase().indexOf(arg.toUpperCase())>=0;
			};
		});
	}
	$.fn.filterTable = function(options) { // define the filterTable plugin
		var defaults = { // start off with some default settings
				callback:          null,                // callback function: function(term, table){}
				containerClass:    'filter-table',      // class to apply to the container
				containerTag:      'p',                 // tag name of the container
				hideTFootOnFilter: false,               // if true, the table's tfoot(s) will be hidden when the table is filtered
				highlightClass:    'alt',               // class applied to cells containing the filter term
				inputName:         '',                  // name of filter input field
				inputType:         'search',            // tag name of the filter input tag
				label:             'Filter:',           // text to precede the filter input tag
				minRows:           8,                   // don't show the filter on tables with less than this number of rows
				placeholder:       'search this table', // HTML5 placeholder text for the filter field
				quickList:         [],                  // list of phrases to quick fill the search
				quickListClass:    'quick',             // class of each quick list item
				quickListGroupTag: '',                  // tag surrounding quick list items (e.g., ul)
				quickListTag:      'a',                 // tag type of each quick list item (e.g., a or li)
				visibleClass:      'visible',           // class applied to visible rows
				filterElementIds:  []                   // list of filter element ids (can be input or select elements) Ex.: ['#my-input-filter','#my-select-filter'] SELECT element can be linked to a table column by adding the element id as a <th> class.
			},
			hsc = function(text) { // mimic PHP's htmlspecialchars() function
				return text.replace(/&/g, '&amp;').replace(/"/g, '&quot;').replace(/</g, '&lt;').replace(/>/g, '&gt;');
			},
			settings = $.extend({}, defaults, options); // merge the user's settings into the defaults

		var doFiltering = function(table, q, classRow) { // handle the actual table filtering
				var tbody=table.find('tbody'); // cache the tbody element
				if (q==='') { // if the filtering query is blank
					tbody.find('tr').show().addClass(settings.visibleClass); // show all rows
					tbody.find('td').removeClass(settings.highlightClass); // remove the row highlight from all cells
					if (settings.hideTFootOnFilter) { // show footer if the setting was specified
						table.find('tfoot').show();
					}
				} else { // if the filter query is not blank
					tbody.find('tr').hide().removeClass(settings.visibleClass); // hide all rows, assuming none were found
					if (settings.hideTFootOnFilter) { // hide footer if the setting was specified
						table.find('tfoot').hide();
					}
					var table_td_selector = 'td';
					if (typeof classRow != 'undefined' && $('th.'+classRow).length > 0) { // if a filterelementid is linked to a column (<th>)
						var th_index = $('th.'+classRow).get(0).cellIndex+1;
						table_td_selector += ':nth-child('+th_index+')';
					}
					tbody.find('td').removeClass(settings.highlightClass); // remove highlights
					tbody.find(table_td_selector).filter(':filterTableFind("'+q.replace(/(['"])/g,'\\$1')+'")').addClass(settings.highlightClass).closest('tr').show().addClass(settings.visibleClass); // highlight (class=alt) only the cells that match the query and show their rows
				}
				if (settings.callback) { // call the callback function
					settings.callback(q, table);
				}
			}; // doFiltering()

		var doReseting = function(activeId) {
				$.each(settings.filterElementIds, function(_index,_elementId) {
					if (_elementId != activeId) $(_elementId).val('');
				});
			};

		return this.each(function() {
			var t = $(this), // cache the table
				tbody = t.find('tbody'), // cache the tbody
				container = null, // placeholder for the filter field container DOM node
				quicks = null, // placeholder for the quick list items
				filter = null; // placeholder for the field field DOM node
			if (t[0].nodeName==='TABLE' && tbody.length>0 && (settings.minRows===0 || (settings.minRows>0 && tbody.find('tr').length>settings.minRows)) && !t.prev().hasClass(settings.containerClass)) { // only if object is a table and there's a tbody and at least minRows trs and hasn't already had a filter added
				container = $('<'+settings.containerTag+' />'); // build the container tag for the filter field
				if (settings.containerClass!=='') { // add any classes that need to be added
					container.addClass(settings.containerClass);
				}
				container.prepend(settings.label+' '); // add the label for the filter field
				if (settings.filterElementIds.length < 1) {
					filter = $('<input type="'+settings.inputType+'" placeholder="'+settings.placeholder+'" name="'+settings.inputName+'" id="jft-'+settings.inputName+'" />'); // build the filter field
					settings.filterElementIds = ['#jft-'+settings.inputName];
					container.append(filter); // add the filter field to the container
					t.before(container); // add the filter field and quick list container to just before the table
				}
				$.each(settings.filterElementIds,function(index,elementId) {
					filter = $(elementId) // get the filter field
					if (filter.length < 1) return true; // continue if not exist
					// Input text
					if (filter.get(0).tagName == 'INPUT') {
						if ($.fn.bindWithDelay) { // does bindWithDelay() exist?
							filter.bindWithDelay('keyup', function() { // bind doFiltering() to keyup (delayed)
								doReseting(elementId);
								doFiltering(t, $(this).val());
							}, 200);
						} else { // just bind to onKeyUp
							filter.bind('keyup', function() { // bind doFiltering() to keyup
								doReseting(elementId);
								doFiltering(t, $(this).val());
							});
						} // keyup binding block
					// Select object
					} else if (filter.get(0).tagName == 'SELECT') {
						filter.change(function() { // bind doFiltering() to select
							doReseting(elementId);
							doFiltering(t, $(this).val(),$(this).attr('id'));
						});
					}
				});
				if (settings.quickList.length>0) { // are there any quick list items to add?
					quicks = settings.quickListGroupTag ? $('<'+settings.quickListGroupTag+' />') : container;
					$.each(settings.quickList, function(index, value) { // for each quick list item...
						var q = $('<'+settings.quickListTag+' class="'+settings.quickListClass+'" />'); // build the quick list item link
						q.text(hsc(value)); // add the item's text
						if (q[0].nodeName==='A') {
							q.attr('href', '#'); // add a (worthless) href to the item if it's an anchor tag so that it gets the browser's link treatment
						}
						q.bind('click', function(e) { // bind the click event to it
							e.preventDefault(); // stop the normal anchor tag behavior from happening
							filter.val(value).focus().trigger('click'); // send the quick list value over to the filter field and trigger the event
						});
						quicks.append(q); // add the quick list link to the quick list groups container
					}); // each quick list item
					if (quicks!==container) {
						container.append(quicks); // add the quick list groups container to the DOM if it isn't already there
					}
				} // if quick list items
			} // if the functionality should be added
		}); // return this.each
	}; // $.fn.filterTable
})(jQuery);