Archive for the ‘ jQuery ’ Category

jQuery clone() bug in Internet Explorer

Ran into an interesting bug this morning with jQuery 1.2.2.  After testing a simple working jQuery function in FF, I then tested in IE and found that it didn’t work in IE.  The jQuery code is fairly straightforward, so I was extremely perplexed.

$("#existingFacilities").dblclick(function() {
	$("#selectedFacilities").append($("#existingFacilities option:selected").clone());
});

All this does is clone an option from one select box and append it to another when it is double-clicked. After a few minutes of debugging, I removed the clone() function and it worked. For some reason, IE won’t work with cloned objects in jQuery. So instead of having a copy of the same option in two select boxes, it’s removed from the first and added to the second.

Here’s my workaround.

$("#existingFacilities").dblclick(function() {
	var selectedOption = $("#existingFacilities option:selected");
	var newOption = new Option($(selectedOption).text(), $(selectedOption).val());
	var ops = $("#selectedFacilities").attr("options");

	if( typeof(ops) != "undefined" )
		ops[ops.length] = newOption;
	else
		$("#selectedFacilities").append(selectedOption.clone());
});

Hope this helps someone.

jQuery 1.2.2 Released

jQuery 1.2.2 was announced today. Though this is a revision release, it’s a significant one and definitely worth considering an upgrade to your existing jQuery implementations.  If for nothing else, the 300% speed improvement for DOMElement.

You can download in several flavors:

jQuery 1.2.2 Release Notes

If you build web applications, at some point you have built a form that had dynamically named form elements. You loop through a CFQUERY and build some input fields that’s a combination of a string ID and a ColdFusion variable (usually currentRow).

<cfloop query="aSimpleQuery"><cfoutput>
	<input type="hidden" id="columnOne_#currentRow#" value="#columnOneValue#">
	<input type="hidden" id="columnTwo_#currentRow#" value="#columnTwoValue#">
</cfoutput></cfloop>

I’ve seen a lot of developers struggle with how to then easily identify these fields via Javascript in order to modify/read their values, change the styles, or build a complex data structure from the values.

The power of jQuery’s DOM traverser makes it a snap. It’s just a RegEx expression to find the elements you need. You can also use the built-in function each() for looping over the elements instead of making a for loop.

$("input[id^='columnOne_']").each(function(i) {
	if( this.val() != 0 ) {
		// Do something really cool here
	}
}

At this point, you may be thinking, “Yeah, but what about checkboxes, eh?!? And what if they have name attributes, but no ID??” No problem, just use an even more advanced jQuery selector and the code remains the same.

$("input[name^='columnOne_']:checkbox").each(function(i) {
	if( this.val() != 0 ) {
		// Do something really cool here
	}
}

Take a look-see at all of the jQuery selectors and you’ll see how easy they make it to find DOM elements.

These three Javascript libraries are at the core of how I build fun, well-organized, and easy to maintain web applications. Each one serves a different purpose:

  • jQuery – The best at DOM selection, manipulation and searching
  • Ext – Makes all my little widgets look great and fun for the users
  • ajaxCFC – Handles calls to my business logic and serialization of data

I’ll start off with a nice example of how these three libraries play well together and can make an otherwise complicated action very simple and easy to write.

This code has three pieces of functionality. I’m using the jQuery Datepicker on my page, and when the user selects a date from the calendar, I want the database to immediately be updated with the date chosen. If the method fails, throw up a nice message box with a failure message and ask the user to try again.

// Use jQuery to bind the dataSelected event of the jQuery DatePicker
$('#requestDueDate').bind('dateSelected',function(e, selectedDate, $td){
        // Use ajaxCFC to call the updateRequestDates() function of the Request component
	$.AjaxCFC({
		url: "model/ajax/request/Request.cfc",
		useDefaultErrorHandler: false,
		method: "updateRequestDates",
		data: { 'request_hdr_seq_no': request_hdr_seq_no,
			'request_due_date': selectedDate.asString(),
			'test_completion_date':$("#testCompletionDate").val() },
		timeout:30000,
		success: submitRequestCheck,
		error: function(results) {
                        // If the call fails, throw up an Ext message box to alert the user
			Ext.MessageBox.alert('Update Failed', "Failed to update the request due date. Please try again.");
			$('input#testCompletionDate').val("");
		}
	});
});

All I was required to do was write 14 lines of code. Now, I can’t even imagine having to write this code without the use of the Big 3.

Now for one of my favorite features of this site (it’s actually a boring feature, but how I implemented it is cool).
Notes Accordion Dialog II

This is just a simple note feature where users can record any pertinent information about the work they are performing. I’m using the Ext Accordion Widget to display all past notes. You can see how the user can expand and contract each note item – not really needed, but never hurts to wow the users a little.

This particular page was written to operate as a true application. Any changes to the UI are immediately written to the database via AJAX calls. The UI is then updated when the operation completes, and the user can continue working while several tasks are being executed. No page reloads at all.

So when they add a note, it must be inserted into the database, and the Accordian object must have a new panel added to it, with the new text inserted inside.

I’ll admit, it stretched all my capabilities and imagination for Javascript programming. All in all, it took over 3 days of trying different things, and research, to get it to work.

First, I had to include the required features of the libraries.

<script type="text/javascript" src="js/jquery.AjaxCFC.js"></script>
<script type="text/javascript" src="js/json.js"></script>

<script type="text/javascript" src="js/ext-buttons.js"></script>
<script type="text/javascript" src="js/ext-layout.js"></script>
<script type="text/javascript" src="js/Ext.ux.InfoPanel.js"></script>
<script type="text/javascript" src="js/Ext.ux.Accordion.js"></script>

*This adds up to 300k of jQuery/Ext Javascript libraries.

Then, I build the <div> element that will be used to display the dialog and the accordion panels

<div id="NoteModalDialog">
	<div class="x-dlg-hd">Request Notes</div>
	<div class="x-dlg-bd">
       	<div class="x-dlg-tab" title="Notes">
			<div id="RequestNoteForm"></div>
			<div style="font-size:1.1em; font-weight:800;">Previous Notes</div>
			<div id="acc-ct" style="width:100%; height:200px">
				<cfloop query="requestNotesQuery">
					<cfoutput>
					<div id="panel-#currentRow#">
						<div>
							#first_name# #last_name# - #setup_date#:
						</div>
						<div>
							<div class="text-content">#note_txt#</div>
							<div style="border-bottom:5px solid white;"></div>
						</div>
					</div>
					</cfoutput>
				</cfloop>
			</div>
		</div>
	</div>
</div>

Then I instantiate the accordion object and build all the panels with previous notes

$(document).ready(function(){
	// Create accordion to hold previous notes in note popup
	var accordion = new Ext.ux.Accordion('acc-ct', { height:400,independent:true});

	// Create a panel for each previous note
	<cfloop query="requestNotesQuery"><cfoutput>
		var panel#currentRow# = accordion.add(new Ext.ux.InfoPanel('panel-#currentRow#', {collapsed:false}));
	</cfoutput></cfloop>
}

Then, of course, I need my wonderful Javascript object that handles building the dialog, saving the note, and loading of previous notes back into the UI/DOM.

It first builds a dynamic Ext form (which includes validation).

var noteForm = new Ext.form.Form({ labelWidth:25 });
var noteText = new Ext.form.TextArea({
	fieldLabel: 'Note',
	name: 'noteText',
	width:375,
	allowBlank:false,
	grow:true,
	growMax:200,
	emptyText:"Enter your request notes here..."
});
noteForm.add(noteText);

Then using ajaxCFC, I insert the data into database

$.AjaxCFC({
	url: "model/ajax/note/Note.cfc",
	useDefaultErrorHandler: false,
	method: "add",
	async:false,
	data: { 'seq_no': request_hdr_seq_no, 'note_type':'REQUESTHDR', 'note_txt': noteText.getValue() },
	timeout:30000,
	success: function(results) {
		// Reset the note field to blank
		noteText.setRawValue("");

		{{ This nested ajaxCFC call code shown below }}
	},
	error: function(results) {
		Ext.MessageBox.alert('Save Failed', results.responseText);
	}
});

Upon success of the insertion of the data, update the UI by adding a panel to the Accordion object with the new note inside.

// Return all notes from the database for this request
$.AjaxCFC({
	url: "model/ajax/request/Request.cfc",
	useDefaultErrorHandler: false,
	method: "getAllRequestNotes",
	async:false,
	data: { 'request_hdr_seq_no': request_hdr_seq_no },
	timeout:30000,
	success: function(results) {
		// Empty out the current accordion object and re-populate it with a panel for each note
		var panel = new Object();
		var accordion = new Ext.ux.Accordion('acc-ct', { height:'400', independent:true });
		$("#acc-ct").empty();

		for(i=0; i<results.NOTECOUNT;i++) {
			$("#acc-ct").append('<div id="panel-' + i + '"><div>' + results.PANELS[i].FIRST_NAME + ' ' + results.PANELS[i].LAST_NAME + ' - ' +    results.PANELS[i].SETUP_DATE + '</div><div><div class="text-content">' + results.PANELS[i].NOTE_TXT + '</div></div></div>');
			panel[i] = accordion.add(new Ext.ux.InfoPanel('panel-'+i, {collapsed:false}));
		}
	},
	error: function(results) {
		Ext.MessageBox.alert('UI Update Failed', "Failed to update Notes popup with latest note.");
	}
});

I put it all together, and I get a self-documenting, elegant Javascript object that handles user notes.

// Create the object that will be used for the Request Notes popup
var requestNotesEdit = function() {
	var dialog;
	var noteForm = new Ext.form.Form({ labelWidth:25 });
	var noteText = new Ext.form.TextArea({
		fieldLabel: 'Note',
		name: 'noteText',
		width:375,
		allowBlank:false,
		grow:true,
		growMax:200,
		emptyText:"Enter your request notes here..."
	});
	noteForm.add(noteText);

	return {
		init : function() { this.buildDialog(); },
		saveData : function() {
			if (noteForm.isValid()) {

				$.AjaxCFC({
					url: "model/ajax/note/Note.cfc",
					useDefaultErrorHandler: false,
					method: "add",
					async:false,
					data: { 'seq_no': request_hdr_seq_no, 'note_type':'REQUESTHDR', 'note_txt': noteText.getValue() },
					timeout:30000,
					success: function(results) {
						// Reset the note field to blank
						noteText.setRawValue("");

						// Return all notes from the database for this request
						$.AjaxCFC({
							url: "model/ajax/request/Request.cfc",
							useDefaultErrorHandler: false,
							method: "getAllRequestNotes",
							async:false,
							data: { 'request_hdr_seq_no': request_hdr_seq_no },
							timeout:30000,
							success: function(results) {

								// Empty out the current accordion object and re-populate it with a panel for each note
								var panel = new Object();
								var accordion = new Ext.ux.Accordion('acc-ct', { height:'400', independent:true });
								$("#acc-ct").empty();

								for(i=0; i<results.NOTECOUNT;i++) {
									$("#acc-ct").append('<div id="panel-' + i + '"><div>' + results.PANELS[i].FIRST_NAME + ' ' + results.PANELS[i].LAST_NAME + ' - ' +    results.PANELS[i].SETUP_DATE + '</div><div><div class="text-content">' + results.PANELS[i].NOTE_TXT + '</div></div></div>');
									panel[i] = accordion.add(new Ext.ux.InfoPanel('panel-'+i, {collapsed:false}));
								}
							},
							error: function(results) {
								Ext.MessageBox.alert('UI Update Failed', "Failed to update Notes popup with latest note.");
							}
						});

					},
					error: function(results) {
						Ext.MessageBox.alert('Save Failed', results.responseText);
					}
				});

				dialog.hide();
			}else{
				Ext.Msg.alert('Field Required', 'Please enter in some note text before submitting.');
			}
		},
		buildDialog : function() {
			noteForm.render('RequestNoteForm');
			dialog = new Ext.BasicDialog("NoteModalDialog", {
				modal:true,
			    width:450,
			    height:350,
			    shadow:true,
			    minWidth:400,
			    minHeight:300,
			    animateTarget:'requestNotes'
			});
			dialog.addKeyListener(27, this.hideWindow, this);
	        dialog.addButton('Save', this.saveData, this);
	        dialog.addButton('Cancel', this.hideWindow, this);
		},
		showWindow : function() { dialog.show(); },
		hideWindow : function() { dialog.hide(); }
	};
};