The Ext JS 3.0 Cookbook is for developers who want a book of useful techniques, with explanations, that they can refer to and adapt to their purposes.

I was a Technical Reviewer for this book, and it contains not just simple recipes to get you started, but complex ones to allow you to bend Ext JS to your will. If you buy Ext JS 3.0 Cookbook eBook along with the eBook edition of the book I co-authored, Learning Ext JS, you can get a 50% discount using the promo code jsco34ler on the Packt website. Congratulations Jorge!

“How can it cost so much?! It’s just a website!”

I can see their point. Most websites contain common elements – login, lists, articles, shopping carts, and so on – so you’d think that once you’ve written one, you’ll have the bits and pieces you need to make more. And taken individually, each of these parts are fairly straightforward – a list of products contains some pretty basic HTML, surely? And HTML is just a text file?

And again, that’s a fair point. The real time isn’t taken in writing these bits and pieces, it’s taken in understanding how the customer wants them to be written and how they need to fit together in a certain situation. For example, a shopping cart quickly becomes more complex when the customer adds on a few more features:

• Integrates with Google Checkout
• Customers can save carts for later ordering
• Customers can reload past orders into a few cart

But it’s not just the cart, it’s viewing products too – what if certain customers see custom trade prices? Or products can be assigned to multiple categories and the customer wants to see how many products are in each category next to the category name? All of these things are minor when taking in isolation, but together they are a thousand tiny cuts which bleed development time.

As well as a collection of features, a specification for a website will also discuss requirements in language which is specific to the company you’re quoting for. Rather than “cart” you might have “basket”. Or you could have “assessors”, “reviewers”, “investigators”, or any other number of terms which a company uses internally and when referencing all of the features they want on their site. Eric Evans talks about the “domain” of a problem when discussing software – not only do you have to appreciate what kind of features are necessary but you have to understand the domain in which they’re going to be used, in order to create a solution which fits together correctly.

So software is a whole big bag of questions and clarifications and solutions. From a developer’s point of view, it’s not just a case of taking some standard components and piecing them together – though that does happen occasionally. Instead every step of the development process is about solving problems, by understanding what the customer wants and by understanding the problem domain. Every day of development sees a developer tackle a new bit of work that needs resolving in a novel way, and that’s why making software isn’t just a case of shoving some parts together and hoping that it works, but a process, an evolution of the initial ideas.

When clients come to us and ask for software, they’ll pitch it by saying “make us a website”. But we know that what they really mean is “look, understand, and solve our problem”. And that’s what we do.

I am not going to go into detail about this feature as Ryan Daigle has an excellent write up on his blog.

However I have been looking at ways to easily add and remove nested form blocks using Javascript/RJS and came across a good method of achieving this by Marsvin on the RailsForum website.

We have used this method a few times now, so thought we would roll it up into a plugin. Simply install the plugin to give you two new view helpers that allow you to create links to add and remove these nested form item partials using RJS.

Visit the plugin’s page on GitHub to install or view the documentation.

My favourite use of this feature is for development – when you’re sending loads of test emails you can avoid polluting your inbox and simply check the pickup directory. You also avoid having to set up an SMTP host and all of the associated configuration.

Simply add the following to your web.config’s system.net section:

<mailSettings>
	<smtp deliveryMethod="SpecifiedPickupDirectory">
		<specifiedPickupDirectory pickupDirectoryLocation="c:\temp\"/>
	</smtp>
</mailSettings>

Make sure you’ve got the right permissions on the directory. Now, send an email from your application and watch it appear in c:\temp, as if by magic!

I have recently been doing Cocoa Development on Mac OS X 10.5 and was looking for a way to do this in Cocoa and came across a great drawing method named NSDrawNinePartImage. The method has the following signature:

void NSDrawNinePartImage(NSRect frame,
   NSImage *topLeftCorner,
   NSImage *topEdgeFill,
   NSImage *topRightCorner,
   NSImage *leftEdgeFill,
   NSImage *centerFill,
   NSImage *rightEdgeFill,
   NSImage *bottomLeftCorner,
   NSImage *bottomEdgeFill,
   NSImage *bottomRightCorner,
   NSCompositingOperation op,
   CGFloat alphaFraction,
   BOOL flipped
);

This method requires the developer to provide 9 separate images to create the 9 sections of the scale 9 image. Luckily the article I had stumbled across had a handy example for using a single class, so I thought that I would use their technique to create a simple generic class that can be used to draw a single NSImage as a Scale-9 scalable image. This could be used for example in an NSView or NSButtonCell.

//
//  GTDrawImage.m
//  StretchMyView
//
//  Created by Jon Baker on 17/06/2009.
//  Copyright 2009 Go Tripod Ltd. All rights reserved.
//
 
#import "GTDrawImage.h"
 
@implementation GTDrawImage
 
 
+(void) drawScalableImage:(NSImage *)sourceImage scaleTopLeft:(NSPoint)topLeftPoint scaleBottomRight:(NSPoint)bottomRightPoint inFrame:(NSRect)frame
{
	NSSize sourceSize = [sourceImage size];
 
	// Top left
	NSRect topLeftTileRect = NSMakeRect(0, 0, topLeftPoint.x, sourceSize.height - topLeftPoint.y);
	NSRect topLeftCutRect = NSMakeRect(0, topLeftPoint.y, topLeftTileRect.size.width, topLeftTileRect.size.height);
 
	// TopRight
	NSRect topRightTileRect = NSMakeRect(0,0, sourceSize.width - bottomRightPoint.x, topLeftTileRect.size.height);
	NSRect topRightCutRect = NSMakeRect(sourceSize.width - topRightTileRect.size.width, topLeftPoint.y, topRightTileRect.size.width, topRightTileRect.size.height);
 
	// Top
	NSRect topTileRect = NSMakeRect(0, 0, sourceSize.width - topLeftTileRect.size.width - topRightTileRect.size.width, topLeftTileRect.size.height);
	NSRect topCutRect = NSMakeRect(topLeftPoint.x, topLeftPoint.y, topTileRect.size.width, topTileRect.size.height);
 
	// Bottom Left
	NSRect bottomLeftTileRect = NSMakeRect(0, 0, topLeftCutRect.size.width, bottomRightPoint.y);
	NSRect bottomLeftCutRect = NSMakeRect(0, 0, bottomLeftTileRect.size.width, bottomLeftTileRect.size.height);
 
	// Bottom Right
	NSRect bottomRightTileRect = NSMakeRect(0,0, topRightCutRect.size.width, bottomLeftTileRect.size.height);
	NSRect bottomRightCutRect = NSMakeRect(topRightCutRect.origin.x, 0, bottomRightTileRect.size.width , bottomRightTileRect.size.height );
 
	// Bottom
	NSRect bottomTileRect = NSMakeRect(0,0, topTileRect.size.width, bottomLeftTileRect.size.height);
	NSRect bottomCutRect = NSMakeRect(topCutRect.origin.x, 0, bottomTileRect.size.width, bottomTileRect.size.height);
 
	// left
 
	NSRect leftTileRect = NSMakeRect(0, 0, bottomLeftTileRect.size.width, sourceSize.height - topTileRect.size.height - bottomTileRect.size.height);
	NSRect leftCutRect = NSMakeRect(0, bottomRightPoint.y, leftTileRect.size.width, leftTileRect.size.height);
 
	// right
 
	NSRect rightTileRect = NSMakeRect(0, 0, topRightCutRect.size.width, leftCutRect.size.height);
	NSRect rightCutRect = NSMakeRect(bottomRightPoint.x, bottomRightPoint.y, rightTileRect.size.width, rightTileRect.size.height);
 
	//center
	NSRect centerTileRect = NSMakeRect(0, 0, topTileRect.size.width, leftTileRect.size.height);
	NSRect centerCutRect = NSMakeRect(topCutRect.origin.x, bottomRightPoint.y, centerTileRect.size.width, centerTileRect.size.height);
 
	NSImage *topLeft = [[NSImage alloc] initWithSize:topLeftTileRect.size];
	[topLeft lockFocus];
	[sourceImage drawInRect:topLeftTileRect fromRect:topLeftCutRect operation:NSCompositeCopy fraction:1.0];
	[topLeft unlockFocus];
 
	NSImage *top = [[NSImage alloc] initWithSize:topTileRect.size];
	[top lockFocus];
	[sourceImage drawInRect:topTileRect fromRect:topCutRect operation:NSCompositeCopy fraction:1.0];
	[top unlockFocus];
 
	NSImage *topRight = [[NSImage alloc] initWithSize:topRightTileRect.size];
	[topRight lockFocus];
	[sourceImage drawInRect:topRightTileRect fromRect:topRightCutRect operation:NSCompositeCopy fraction:1.0];
	[topRight unlockFocus];
 
	//setup center section, left, right
	NSImage *left = [[NSImage alloc] initWithSize:leftTileRect.size];
	[left lockFocus];
	[sourceImage drawInRect:leftTileRect fromRect:leftCutRect operation:NSCompositeCopy fraction:1.0];
	[left unlockFocus];
 
	NSImage *center = [[NSImage alloc] initWithSize:centerTileRect.size];
	[center lockFocus];
	[sourceImage drawInRect:centerTileRect fromRect:centerCutRect operation:NSCompositeCopy fraction:1.0];
	[center unlockFocus];
 
	NSImage *right = [[NSImage alloc] initWithSize:rightTileRect.size];
	[right lockFocus];
	[sourceImage drawInRect:rightTileRect fromRect:rightCutRect operation:NSCompositeCopy fraction:1.0];
	[right unlockFocus];
 
	NSImage *bottomLeft = [[NSImage alloc] initWithSize:bottomLeftTileRect.size];
	[bottomLeft lockFocus];
	[sourceImage drawInRect:bottomLeftTileRect fromRect:bottomLeftCutRect operation:NSCompositeCopy fraction:1.0];
	[bottomLeft unlockFocus];
 
	NSImage *bottom = [[NSImage alloc] initWithSize:bottomTileRect.size];
	[bottom lockFocus];
	[sourceImage drawInRect:bottomTileRect fromRect:bottomCutRect operation:NSCompositeCopy fraction:1.0];
	[bottom unlockFocus];
 
	NSImage *bottomRight = [[NSImage alloc] initWithSize:bottomRightTileRect.size];
	[bottomRight lockFocus];
	[sourceImage drawInRect:bottomRightTileRect fromRect:bottomRightCutRect operation:NSCompositeCopy fraction:1.0];
	[bottomRight unlockFocus];
 
 
	NSDrawNinePartImage(
						frame,
						topLeft, top, topRight,
						left, center, right,
						bottomLeft, bottom, bottomRight,
						NSCompositeSourceOver, 1.0, NO);
 
	[topLeft release];
	[top release];
	[topRight release];
	[left release];
	[center release];
	[right release];
	[bottomLeft release];
	[bottom release];
	[bottomRight release];
}
 
@end

To use this generic classes, you simply need to import it where required:

#import "GTDrawImage.h"

…and then you can call from within, for example the drawRect:, selector using the following method:

- (void)drawRect:(NSRect)rect {
	[GTDrawImage drawScalableImage:baseImage scaleTopLeft:NSMakePoint(8, 16) scaleBottomRight:NSMakePoint(16,8) inFrame: [self bounds]];
}

drawScalableImage takes an NSImage, in this case baseImage, and two reference points (NSPoint) to split the image into nine slices, firstly the scaleTopLeft: and secondly the scaleBottomRight:, both located from the bottom left corner. So for example to split a 24px x 24px image into 9 equal 8px by 8px segments (see below), the topLeftPoint would be x=8px, y=16px and the bottom x=16 and y=8.

Just download the following classes into your projects and away you go:

• Header: GTDrawImage.h
• Implementation: GTDrawImage.m
• Sample Project using GTDrawImage: StretchMyView.zip (Adapted example I found. Unfortunately I can’t remember where and so don’t know who to credit)

This is a great way to capture the interest of would be browsers that would normally see this page and immediately hit the back key, instead not only do they capture my attention, but they also tap into my curiosity which gets me to immediately click the products link.

In this case I didn’t need any of their products but this is a great tip.

Also note the search bar being visible. This is essential on a 404 page for keeping customers that know what they are looking for on your site.

gem update --system

Then install the Phusion Passenger gem

gem install passenger

Once complete you can run the Phusion Passenger install that compiles mod_rails for you.

passenger-install-apache2-module

Once this completes it will give you some code to past into your httpd.conf file and you are ready to start configuring your sites.. Well actually if you have been using Mongrels then time to strip most of the configuration out of your https.conf file. You can have as simple a configuration as shown below. Note: The DocumentRoot should be set to the public folder within your app. Passenger automatically detects that this is a rails app.

    ServerName www.stubmatic.com
    DocumentRoot /websites/stubmatic/public

One thing to note is that by default Passenger disables ModRewrite for that VirtualHost and in our case we use ModRewrite for a number of things such as providing a Maintenance page when maintenance.html is in our public folder allowing us to take the app offline. We also use ModRewrite to hide .svn folders, so we needed to use ModRewrite. Thankfully Passenger provides a solution. Note: You must first make sure you remove the .htaccess file in your rails public folder!

So our new Apache configuration looks like this:

    ServerName www.stubmatic.com
    DocumentRoot /websites/stubmatic/public
 
    RailsAllowModRewrite on
 
    RewriteEngine On
 
    RewriteRule ^(.*/)?.svn/ - [F,L]
 
    RewriteCond %{DOCUMENT_ROOT}/maintenance.html -f
    RewriteCond %{SCRIPT_FILENAME} !maintenance.html
    RewriteRule ^.*$ /maintenance.html [L]

If you want to setup an Apache / Phusion Passenger testing server you will also need to add the following directive to your VirtualHost configuration:

RailsEnv development

As you can see Phusion Passenger make deployment of Ruby on Rails as trivial as deploying a PHP. You can easily reload Phusion Passenger by running the following command from within your Rails project root.

touch tmp/restart.txt

In terms of performance, Phusion Passenger holds it’s own against Mongrel and there are plenty of details on Phusion’s website.

For more information:

1. Phusion Passenger
2. Phusion Passenger Documentation

iPhone and Adobe Air developers (as well as any others that use SQLite 3) Menial has just released an excellent little app for creating, managing and running queries against SQLite 3 databases called Bases.

The application is simple to use, very user friendly and has worked well from the testing I have done. It costs just £10 and there is a free trial available so you can try before you buy.

Find out more and download here

**** UPDATE: ActiveMerchant recently removed the functionality to use PayPal’s NVP API and so this code will no longer work with the latest ActiveMerchant. Raymond Law has kindly ported the code to use the SOAP API and you can find out more information and usage on his blog. ****

Active Merchant is very easy to extend so I have written a Ruby class that can be dropped into /vendor/plugins/active_merchant/billing/gateways/ within your Rails project (assuming you have AM installed as a plugin)

Below is the code: (I have also attached the .rb file: paypal_express_recurring_nv.rb)

# simple extension to ActiveMerchant for basic support of recurring payments with Express Checkout API
#
# See http://http://www.gotripod.com/2008/09/07/ruby-on-rails-paypal-express-recurring-payments-using-active-merchant/
# for details on getting started with this gateway
#
#
module ActiveMerchant #:nodoc:
  module Billing #:nodoc:
    class PaypalExpressRecurringNvGateway < Gateway
      include PaypalNvCommonAPI
 
      LIVE_REDIRECT_URL = 'https://www.paypal.com/cgibin/webscr?cmd=_customer-billing-agreement&token='
      TEST_REDIRECT_URL = 'https://www.sandbox.paypal.com/cgi-bin/webscr?cmd=_customer-billing-agreement&token='
 
      def redirect_url
        test? ? TEST_REDIRECT_URL : LIVE_REDIRECT_URL
      end
 
      def redirect_url_for(token)
          "#{redirect_url}#{token}"
      end
 
      def setup_agreement(description, options = {})
        requires!(options, :return_url, :cancel_return_url)
        commit 'SetCustomerBillingAgreement', build_setup_agreement(description, options)
      end
 
      def get_agreement(token)
        commit 'GetBillingAgreementCustomerDetails', build_get_agreement(token)
      end
 
      def create_profile(money, token, options = {})
        commit 'CreateRecurringPaymentsProfile', build_create_profile(money, token, options)
      end
 
      def get_profile_details(profile_id)
        commit 'GetRecurringPaymentsProfileDetails', build_get_profile_details(profile_id)
      end
 
      def manage_profile(profile_id, action, options = {})
        commit 'ManageRecurringPaymentsProfileStatus', build_manage_profile(profile_id, action, options)
      end
 
      def update_profile(profile_id, options = {})
        commit 'UpdateRecurringPaymentsProfile', build_update_profile(profile_id, options)
      end
 
      def bill_outstanding(profile_id, money, options = {})
        commit 'BillOutstandingAmount', build_bill_outstanding(profile_id, money, options)
      end
 
      private
 
      def build_setup_agreement(description, options)
        post = {}
        add_pair(post, :billingagreementdescription, description)
        add_pair(post, :returnurl, options[:return_url])
        add_pair(post, :cancelurl, options[:cancel_return_url])
        add_pair(post, :billingtype, "RecurringPayments")
        add_pair(post, :paymenttype, options[:payment_type]) if options[:payment_type]
        add_pair(post, :localecode, options[:locale]) if options[:locale]
        add_pair(post, :billingagreementcustom, options[:custom_code]) if options[:custom_code]
        post
      end
 
      def build_get_agreement(token)
        post = {}
        add_pair(post, :token, token)
        post
      end
 
      def build_create_profile(money, token, options)
        post = {}
        add_pair(post, :token, token)
        add_amount(post, money, options)
        add_pair(post, :subscribername, options[:subscriber_name]) if options[:subscriber_name]
        add_pair(post, :initamt, options[:initamt]) if options[:initamt]
        add_pair(post, :failedinitamtaction, options[:failedinitamtaction]) if  options[:failedinitamtaction]
        add_pair(post, :profilestartdate, Time.now.utc.iso8601)
        add_pair(post, :billingperiod, options[:billing_period] ? options[:billing_period] : "Month")
        add_pair(post, :billingfrequency, options[:billing_frequency] ? options[:billing_frequency] : 1)
        add_pair(post, :totalbillingcycles, options[:billing_cycles]) if [:billing_cycles]
        add_pair(post, :profilereference, options[:reference]) if options[:reference]
        add_pair(post, :autobillamt, options[:auto_bill_amt]) if options[:auto_bill_amt]
        add_pair(post, :maxfailedpayments, options[:max_failed_payments]) if options[:max_failed_payments]
        add_pair(post, :shippingamt, amount(options[:shipping_amount]), :allow_blank => false) if options[:shipping_amount]
        add_pair(post, :taxamt, amount(options[:tax_amount]), :allow_blank => false) if options[:tax_amount]
        add_shipping_address(post, options[:shipping_address]) if options[:shipping_address]
        post
      end
 
      def build_get_profile_details(profile_id)
        post = {}
        add_pair(post, :profileid, profile_id)
        post
      end
 
      def build_manage_profile(profile_id, action, options)
        post = {}
        add_pair(post, :profileid, profile_id)
        add_pair(post, :action, action)
        add_pair(post, :note, options[:note]) if options[:note]
        post
      end
 
      def build_update_profile(profile_id, options)
        post = {}
        add_pair(post, :profileid, profile_id)
        add_pair(post, :note, options[:note]) if options[:note]
        add_pair(post, :desc, options[:description]) if options[:description]
        add_pair(post, :subscribername, options[:subscriber_name]) if options[:subscriber_name]
        add_pair(post, :profilereference, options[:reference]) if options[:reference]
        add_pair(post, :additionalbillingcycles, options[:additional_billing_cycles]) if options[:additional_billing_cycles]
        add_amount(post, options[:money], options)
        add_pair(post, :shippingamt, amount(options[:shipping_amount]), :allow_blank => false) if options[:shipping_amount]
        add_pair(post, :autobillamt, options[:auto_bill_amt]) if options[:auto_bill_amt]
        add_pair(post, :maxfailedpayments, options[:max_failed_payments]) if options[:max_failed_payments]
        add_pair(post, :taxamt, amount(options[:tax_amount]), :allow_blank => false) if options[:tax_amount]
        add_shipping_address(post, options[:shipping_address]) if options[:shipping_address]
        post
      end
 
      def build_bill_outstanding(profile_id, money, options = {})
        post = {}
        add_pair(post, :profileid, profile_id)
        add_amount(post, money, options)
        add_pair(post, :note, options[:note]) if options[:note]
        post
      end
 
      def build_response(success, message, response, options = {})
        PaypalExpressNvResponse.new(success, message, response, options)
      end
 
    end
  end
end

With this class installed using Active Merchant to set up a subscription / recurring payment through PayPal Express Checkout is easy. Firstly setup your gateway object:

gw = ActiveMerchant::Billing::PaypalExpressRecurringNvGateway.new( :login => 'PAYPALEMAIL', :password => 'PASSWORD', :signature => 'PAYPALAPISIGNATURE' )

Then make a request to PayPal to setup the recurring payment. At this stage you pass through a description (which is what is shown to the user when they are asked to authorise the subscription so make it descriptive) and you also need to provide URLs on your site, that PayPal should redirect the subscriber back to when they either complete the payment, or alternatively if they choose to cancel.

response = gw.setup_agreement("Subscription £25 per month", :cancel_return_url => "https://mysite.com/cancel", :return_url => "https://mysite.com/complete" )

The request above returns us a token in the response from paypal and at this point we need to redirect the user to PayPal to authorise this subscription. The user will see the description “Subscription £25 per month” as sent in the previous request. We need to redirect the subscriber to PayPal using the following line of ruby:

redirect_to gw.redirect_url_for(response.token)

Once the user has authorised the subscription they are returned to the :return_url we specified earlier, at which point we can create the actual subscription using the following:

response = gw.create_profile(2500, response.token, :currency => "GBP", :reference => "34")

Note: PayPal are really confusing having one API for the US and another for the UK but if you are using PayPal Express (which is free) independently of PayPal Website Payments Pro (Which you need to pay for) the US PayPal Express API works for all countries (apart from Germany I believe) and as you can see above I am passing in the UK currency. I am using the US API and I have a UK PayPal account. Also note that I have passed in a reference (I have an IPN URL setup in my PayPal account – Unfortunately you cannot pass an IPN URL with the request) to be sent in the IPN.

The previous step completes the set up of our Subscription. However if we need to later get information on the subscription or change it, we need to extract the Profile ID from the response as follows:

profile_id = response.params["profileid"]

With this profile_id we can then later use these additional methods that I have included, such as getting details of the subscription profile using:

gw.get_profile_details(profile_id)

Update the subscription using various options (i.e. changing subscription amount shown below):

gw.update_profile(profile_id, :money => 3000, :currency => "GBP")

Manage the subscription, for example cancel it as follows:

gw.manage_profile(profile_id, "Cancel", :note => "Your subscription has been cancelled by us")

And finally bill any outstanding subscription balance:

gw.bill_outstanding(profile_id, 2500, :currency=> "GBP", :note => "£20 Overdue Subscription")

Please note that as of yet this class is not part of Active Merchant, however it has been added to Active Merchants case #17 If you want to use this you will have to add it manually as above.

I recommend reading PayPals Express Checkout Integration Guide and the Name Value Pair API Developer Guide and Reference for more information on what variables can be passed in each request to PayPal.

Other than having a very nice logo designed by the guys at Sofa my first impressions are they have implemented Objective-C in javascript. To me this seems an unusual choice as I can’t image there are that many developers (within the web development industry) who are that familiar with Objective-C. Maybe I am wrong, certainly with the current gold rush to develop for the iPhone this will increase. I must admit I have been toying with Objective-C recently and once I got the hang of the syntax am really starting to enjoy it. So maybe there is method to their madness?

The Cappuccino framework has been likened to the recently released (and overhyped in my opinion – seems slow and clunky to me) SproutCore framework. However I am extreamly impressed with how quick 280 Slides responds to user interactions and in addition to this the set of controls provided with Cappuccino have a nicer OS X quality to them.

My personal opinion is that the future of Rich Internet Applications does not lie with Javascript (though I am biased to Flex). It is not that I dislike Javascript, quite the oposite in fact. My reservations mainly lie in Javascript relying too heavily on the HTML DOM and is at the mercy of browsers and their stakeholders (for which there are too many). One of the nices things with technologies such as Flex and Silverlight is the cross browser consistency. Not only this but also the many rich media features such as image manipulation & processing, the ability to do advanced animation including 3D animation, video features etc. which to me put the Rich in Rich Internet Applications.

I may well eat my words as two major players in the form of Apple and Google are backing Javascript as the future standard for RIA development. Google’s Chrome browser addresses some of the performance and stability issues and Apple has recently based it’s online MobileMe business on Javascript (aparently using SpoutCore) as well as introducing new extensions to Javascript such as the Canvas tag that help overcome some of Javascripts shortfalls.

One thing is sure I take my hat off to these guys for pushing the boundaries of Javascript and in particular for implementing Objective-C in Javascript. If you are an Objective-C developer, it is well worth a look as you will be able to quickly develop javascript web applications using a near identical language. If not, check it out anyway. These guys can certainly claim that this is Cocoa for Web Development.

Update

I wanted to include a couple of code snippets (taken from Cappuccino.org) just to illustrate how similar to Objective-C, Objective J is.

In Objective-J classes are declared much like an Objective-C header file:

@implementation Person : CPObject
{
   CPString name;
}
@end

Methods are declared using the identical Objective-C syntax:

- (void)setName:(CPString)aName
{
	name = aName;
}
- (CPString)name
{
	return name;
}

And class methods can be called using a once again similar syntax:

[myPerson setJobTitle: "Founder" company: "280 North"];

Cocoa Master Scott Stevenson has done a nice comparison between Cocoa and Cappuccino, well worth a read..