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jquery UI autocomplete - force selection

jagku
jagku asked
on
Hello Experts,

My code is:   test.html

This has been taken from the jquery UI demo.
I have added a second text input to illustrate the issue.

Currently, if the user types "a", they will get a drop down (correct).
However, if they click on the 2nd text box without selecting from the list, the value of the "Tags" textbox remains as "a". Is it possible to force the user to select from this drop down if they try to move away without selecting an item?

Thanks!
Comment
Watch Question

best way to do this would be to add the 'autoFill' attribute to the function call.

like so :  

	<script>
	$(function() {
		var availableTags = [
			"ActionScript",
			"AppleScript",
			"Asp",
			"BASIC",
			"C",
			"C++",
			"Clojure",
			"COBOL",
			"ColdFusion",
			"Erlang",
			"Fortran",
			"Groovy",
			"Haskell",
			"Java",
			"JavaScript",
			"Lisp",
			"Perl",
			"PHP",
			"Python",
			"Ruby",
			"Scala",
			"Scheme"
		];
		$( "#tags" ).autocomplete({
			source: availableTags, autoFill:true
		});
	});
	</script>

Open in new window


but looks like the version you are using for jquery UI might not support that. try the page using this autocomplete function. coz it works for me when i include this

jQuery.autocomplete = function(input, options) {
	// Create a link to self
	var me = this;

	// Create jQuery object for input element
	var $input = $(input).attr("autocomplete", "off");

	// Apply inputClass if necessary
	if (options.inputClass) $input.addClass(options.inputClass);

	// Create results
	var results = document.createElement("div");
	// Create jQuery object for results
	var $results = $(results);
	$results.hide().addClass(options.resultsClass).css("position", "absolute");
	if( options.width > 0 ) $results.css("width", options.width);

	// Add to body element
	$("body").append(results);

	input.autocompleter = me;

	var timeout = null;
	var prev = "";
	var active = -1;
	var cache = {};
	var keyb = false;
	var hasFocus = false;
	var lastKeyPressCode = null;

	// flush cache
	function flushCache(){
		cache = {};
		cache.data = {};
		cache.length = 0;
	};

	// flush cache
	flushCache();

	// if there is a data array supplied
	if( options.data != null ){
		var sFirstChar = "", stMatchSets = {}, row = [];

		// no url was specified, we need to adjust the cache length to make sure it fits the local data store
		if( typeof options.url != "string" ) options.cacheLength = 1;

		// loop through the array and create a lookup structure
		for( var i=0; i < options.data.length; i++ ){
			// if row is a string, make an array otherwise just reference the array
			row = ((typeof options.data[i] == "string") ? [options.data[i]] : options.data[i]);

			// if the length is zero, don't add to list
			if( row[0].length > 0 ){
				// get the first character
				sFirstChar = row[0].substring(0, 1).toLowerCase();
				// if no lookup array for this character exists, look it up now
				if( !stMatchSets[sFirstChar] ) stMatchSets[sFirstChar] = [];
				// if the match is a string
				stMatchSets[sFirstChar].push(row);
			}
		}

		// add the data items to the cache
		for( var k in stMatchSets ){
			// increase the cache size
			options.cacheLength++;
			// add to the cache
			addToCache(k, stMatchSets[k]);
		}
	}

	$input
	.keydown(function(e) {
		// track last key pressed
		lastKeyPressCode = e.keyCode;
		switch(e.keyCode) {
			case 38: // up
				e.preventDefault();
				moveSelect(-1);
				break;
			case 40: // down
				e.preventDefault();
				moveSelect(1);
				break;
			case 9:  // tab
			case 13: // return
				if( selectCurrent() ){
					// make sure to blur off the current field
					$input.get(0).blur();
					e.preventDefault();
				}
				break;
			default:
				active = -1;
				if (timeout) clearTimeout(timeout);
				timeout = setTimeout(function(){onChange();}, options.delay);
				break;
		}
	})
	.focus(function(){
		// track whether the field has focus, we shouldn't process any results if the field no longer has focus
		hasFocus = true;
	})
	.blur(function() {
		// track whether the field has focus
		hasFocus = false;
		hideResults();
	});

	hideResultsNow();

	function onChange() {
		// ignore if the following keys are pressed: [del] [shift] [capslock]
		if( lastKeyPressCode == 46 || (lastKeyPressCode > 8 && lastKeyPressCode < 32) ) return $results.hide();
		var v = $input.val();
		if (v == prev) return;
		prev = v;
		if (v.length >= options.minChars) {
			$input.addClass(options.loadingClass);
			requestData(v);
		} else {
			$input.removeClass(options.loadingClass);
			$results.hide();
		}
	};

 	function moveSelect(step) {

		var lis = $("li", results);
		if (!lis) return;

		active += step;

		if (active < 0) {
			active = 0;
		} else if (active >= lis.size()) {
			active = lis.size() - 1;
		}

		lis.removeClass("ac_over");

		$(lis[active]).addClass("ac_over");

		// Weird behaviour in IE
		// if (lis[active] && lis[active].scrollIntoView) {
		// 	lis[active].scrollIntoView(false);
		// }

	};

	function selectCurrent() {
		var li = $("li.ac_over", results)[0];
		if (!li) {
			var $li = $("li", results);
			if (options.selectOnly) {
				if ($li.length == 1) li = $li[0];

			} else if (options.selectFirst) {
				li = $li[0];
			}
		}
		if (li) {
			selectItem(li);
			return true;
		} else {
			return false;
		}
	};

	function selectItem(li) {
		if (!li) {
			li = document.createElement("li");
			li.extra = [];
			li.selectValue = "";
		}
		var v = $.trim(li.selectValue ? li.selectValue : li.innerHTML);
		input.lastSelected = v;
		prev = v;
		$results.html("");
		$input.val(v);
		hideResultsNow();
		if (options.onItemSelect) setTimeout(function() { options.onItemSelect(li) }, 1);
	};

	// selects a portion of the input string
	function createSelection(start, end){
		// get a reference to the input element
		var field = $input.get(0);
		if( field.createTextRange ){
			var selRange = field.createTextRange();
			selRange.collapse(true);
			selRange.moveStart("character", start);
			selRange.moveEnd("character", end);
			selRange.select();
		} else if( field.setSelectionRange ){
			field.setSelectionRange(start, end);
		} else {
			if( field.selectionStart ){
				field.selectionStart = start;
				field.selectionEnd = end;
			}
		}
		field.focus();
	};

	// fills in the input box w/the first match (assumed to be the best match)
	function autoFill(sValue){
		// if the last user key pressed was backspace, don't autofill
		if( lastKeyPressCode != 8 ){
			// fill in the value (keep the case the user has typed)
			$input.val($input.val() + sValue.substring(prev.length));
			// select the portion of the value not typed by the user (so the next character will erase)
			createSelection(prev.length, sValue.length);
		}
	};

	function showResults() {
		// get the position of the input field right now (in case the DOM is shifted)
		var pos = findPos(input);
		// either use the specified width, or autocalculate based on form element
		var iWidth = (options.width > 0) ? options.width : $input.width();
		// reposition
		$results.css({
			width: parseInt(iWidth) + "px",
			top: (pos.y + input.offsetHeight) + "px",
			left: pos.x + "px"
		}).show();
	};

	function hideResults() {
		if (timeout) clearTimeout(timeout);
		timeout = setTimeout(hideResultsNow, 200);
	};

	function hideResultsNow() {
		if (timeout) clearTimeout(timeout);
		$input.removeClass(options.loadingClass);
		if ($results.is(":visible")) {
			$results.hide();
		}
		if (options.mustMatch) {
			var v = $input.val();
			if (v != input.lastSelected) {
				selectItem(null);
			}
		}
	};

	function receiveData(q, data) {
		if (data) {
			$input.removeClass(options.loadingClass);
			results.innerHTML = "";

			// if the field no longer has focus or if there are no matches, do not display the drop down
			if( !hasFocus || data.length == 0 ) return hideResultsNow();

			if ($.browser.msie) {
				// we put a styled iframe behind the calendar so HTML SELECT elements don't show through
				$results.append(document.createElement('iframe'));
			}
			results.appendChild(dataToDom(data));
			// autofill in the complete box w/the first match as long as the user hasn't entered in more data
			if( options.autoFill && ($input.val().toLowerCase() == q.toLowerCase()) ) autoFill(data[0][0]);
			showResults();
		} else {
			hideResultsNow();
		}
	};

	function parseData(data) {
		if (!data) return null;
		var parsed = [];
		var rows = data.split(options.lineSeparator);
		for (var i=0; i < rows.length; i++) {
			var row = $.trim(rows[i]);
			if (row) {
				parsed[parsed.length] = row.split(options.cellSeparator);
			}
		}
		return parsed;
	};

	function dataToDom(data) {
		var ul = document.createElement("ul");
		var num = data.length;

		// limited results to a max number
		if( (options.maxItemsToShow > 0) && (options.maxItemsToShow < num) ) num = options.maxItemsToShow;

		for (var i=0; i < num; i++) {
			var row = data[i];
			if (!row) continue;
			var li = document.createElement("li");
			if (options.formatItem) {
				li.innerHTML = options.formatItem(row, i, num);
				li.selectValue = row[0];
			} else {
				li.innerHTML = row[0];
				li.selectValue = row[0];
			}
			var extra = null;
			if (row.length > 1) {
				extra = [];
				for (var j=1; j < row.length; j++) {
					extra[extra.length] = row[j];
				}
			}
			li.extra = extra;
			ul.appendChild(li);
			$(li).hover(
				function() { $("li", ul).removeClass("ac_over"); $(this).addClass("ac_over"); active = $("li", ul).indexOf($(this).get(0)); },
				function() { $(this).removeClass("ac_over"); }
			).click(function(e) { e.preventDefault(); e.stopPropagation(); selectItem(this) });
		}
		return ul;
	};

	function requestData(q) {
		if (!options.matchCase) q = q.toLowerCase();
		var data = options.cacheLength ? loadFromCache(q) : null;
		// recieve the cached data
		if (data) {
			receiveData(q, data);
		// if an AJAX url has been supplied, try loading the data now
		} else if( (typeof options.url == "string") && (options.url.length > 0) ){
			$.get(makeUrl(q), function(data) {
				data = parseData(data);
				addToCache(q, data);
				receiveData(q, data);
			});
		// if there's been no data found, remove the loading class
		} else {
			$input.removeClass(options.loadingClass);
		}
	};

	function makeUrl(q) {
		var url = options.url + "?q=" + encodeURI(q);
		for (var i in options.extraParams) {
			url += "&" + i + "=" + encodeURI(options.extraParams[i]);
		}
		return url;
	};

	function loadFromCache(q) {
		if (!q) return null;
		if (cache.data[q]) return cache.data[q];
		if (options.matchSubset) {
			for (var i = q.length - 1; i >= options.minChars; i--) {
				var qs = q.substr(0, i);
				var c = cache.data[qs];
				if (c) {
					var csub = [];
					for (var j = 0; j < c.length; j++) {
						var x = c[j];
						var x0 = x[0];
						if (matchSubset(x0, q)) {
							csub[csub.length] = x;
						}
					}
					return csub;
				}
			}
		}
		return null;
	};

	function matchSubset(s, sub) {
		if (!options.matchCase) s = s.toLowerCase();
		var i = s.indexOf(sub);
		if (i == -1) return false;
		return i == 0 || options.matchContains;
	};

	this.flushCache = function() {
		flushCache();
	};

	this.setExtraParams = function(p) {
		options.extraParams = p;
	};

	this.findValue = function(){
		var q = $input.val();

		if (!options.matchCase) q = q.toLowerCase();
		var data = options.cacheLength ? loadFromCache(q) : null;
		if (data) {
			findValueCallback(q, data);
		} else if( (typeof options.url == "string") && (options.url.length > 0) ){
			$.get(makeUrl(q), function(data) {
				data = parseData(data)
				addToCache(q, data);
				findValueCallback(q, data);
			});
		} else {
			// no matches
			findValueCallback(q, null);
		}
	}

	function findValueCallback(q, data){
		if (data) $input.removeClass(options.loadingClass);

		var num = (data) ? data.length : 0;
		var li = null;

		for (var i=0; i < num; i++) {
			var row = data[i];

			if( row[0].toLowerCase() == q.toLowerCase() ){
				li = document.createElement("li");
				if (options.formatItem) {
					li.innerHTML = options.formatItem(row, i, num);
					li.selectValue = row[0];
				} else {
					li.innerHTML = row[0];
					li.selectValue = row[0];
				}
				var extra = null;
				if( row.length > 1 ){
					extra = [];
					for (var j=1; j < row.length; j++) {
						extra[extra.length] = row[j];
					}
				}
				li.extra = extra;
			}
		}

		if( options.onFindValue ) setTimeout(function() { options.onFindValue(li) }, 1);
	}

	function addToCache(q, data) {
		if (!data || !q || !options.cacheLength) return;
		if (!cache.length || cache.length > options.cacheLength) {
			flushCache();
			cache.length++;
		} else if (!cache[q]) {
			cache.length++;
		}
		cache.data[q] = data;
	};

	function findPos(obj) {
		var curleft = obj.offsetLeft || 0;
		var curtop = obj.offsetTop || 0;
		while (obj = obj.offsetParent) {
			curleft += obj.offsetLeft
			curtop += obj.offsetTop
		}
		return {x:curleft,y:curtop};
	}
}

jQuery.fn.autocomplete = function(url, options, data) {
	// Make sure options exists
	options = options || {};
	// Set url as option
	options.url = url;
	// set some bulk local data
	options.data = ((typeof data == "object") && (data.constructor == Array)) ? data : null;

	// Set default values for required options
	options.inputClass = options.inputClass || "ac_input";
	options.resultsClass = options.resultsClass || "ac_results";
	options.lineSeparator = options.lineSeparator || "\n";
	options.cellSeparator = options.cellSeparator || "|";
	options.minChars = options.minChars || 1;
	options.delay = options.delay || 200;
	options.matchCase = options.matchCase || 0;
	options.matchSubset = options.matchSubset || 1;
	options.matchContains = options.matchContains || 0;
	options.cacheLength = options.cacheLength || 1;
	options.mustMatch = options.mustMatch || 0;
	options.extraParams = options.extraParams || {};
	options.loadingClass = options.loadingClass || "ac_loading";
	options.selectFirst = options.selectFirst || false;
	options.selectOnly = options.selectOnly || false;
	options.maxItemsToShow = options.maxItemsToShow || -1;
	options.autoFill = options.autoFill || false;
	options.width = parseInt(options.width, 10) || 0;

	this.each(function() {
		var input = this;
		new jQuery.autocomplete(input, options);
	});

	// Don't break the chain
	return this;
}

jQuery.fn.autocompleteArray = function(data, options) {
	return this.autocomplete(null, options, data);
}

jQuery.fn.indexOf = function(e){
	for( var i=0; i<this.length; i++ ){
		if( this[i] == e ) return i;
	}
	return -1;
};

Open in new window


another idea is to add some validation to the text field. match the value to the existing list with a list find and show an error on no match