---
title: WWDC2003 Session 400
framework: wwdc
role: article
path: wwdc/wwdc2003-400
---

# WWDC2003 Session 400

## Transcript

Kind: captions Language: en thank you thank you it's been a long day how you guys doing everybody okay excellent so today's gonna be a really great session for those of you who are either new to the platform or have been here a long time and want to see what's happening the cocoa side we've got two really great people we have Matthew Formica who's a developer technical support engineer and we have t no one who is an application framework engineering they're both going to talk to you about why you should be using cocoa and how cool you can do things with it so let's start with the math you help me thank you Jason we are going to get right in to the material here today what we're going to talk about today is what cocoa is some of you may be here adjacent said for the first time you're not really familiar with cocoa although you may have already heard about it we're also going to talk about what some of the benefits of cocoa are for you as a developer and how you can use it in a variety of application settings and we'll have some demos along the way so let's dive right in what is cocoa well what we like to say is that cocoa is a powerful full-featured easy-to-use object-oriented framework for Mac os10 development and that's kind of a mouthful but basically it means more rapid productivity for you as a developer thanks to its object oriented underpinnings and we we believe at Apple that it is in fact the fastest way to full-featured applications on Mac OS 10 this is an architecture diagram illustrating some of the layers that make up Mac OS 10 at the bottom is Darwin the UNIX layer on top of that stood some graphics technologies courts OpenGL and QuickTime and then the layer of framework these are the layers that your applications will typically right to such things as Java carbon and cocoa and what we're going to focus in on today is cocoa we talk about cocoa as this one monolithic thing but when we drill down a bit we see that there are really two core frameworks that make it up Foundation and app get the way this works is like so foundation is where the non graphical user interface components of cocoa reside such things as strings and networking scripting and file system calls reside here if you're writing an application that doesn't use the user interface you could just linked against foundation and you'd be set however if you do want to use a graphical user interface you'll want to add in app get app kit contains classes for control and windows and all those things that do use the user interface it's part of the application we can actually go beyond this besides these two core object oriented frameworks foundation and app kit there are a variety of other pieces of the system that work together to make the cocoa experience what it is these include things like our development tools project builder and our newly introduced Xcode along with interface builder and their performance tools on the system all have features carefully designed for cocoa development on top of this we have powerful and dynamic languages that provide the support to make cocoa possible Objective C and Java and all of these work together to help you write code faster the framework api's armature they've been around for a long time and they've been designed from the ground up with an object-oriented approach in mind besides this they leverage objective-c and the dynamic runtime that it provides in a few different ways objective-c and cocoa code are weakly typed and so they allow you to reuse more code because the code you write will tend to be more generic right out of the box in addition there aren't there isn't a need for such complexities as templates often a source of confusion in C++ objective see in a dynamic runtime also enable you to create more effective shared frameworks you don't have application binary interface issues like you might with other languages and you can extend base classes without breaking applications that depend on them and thirdly we have this concept of categories this is a language feature which is very powerful you can add methods to existing classes without having the source code to them so for example if you write say a program that's a million lines of code and you use our Unicode compliance string class NS string throughout that code and then discovered is one more method you wish all strings in your program could take advantage of you don't have to go and replace your use of NS string with a subclass simply add a category to NF string and add that method very powerful and all of this adds up to help you be faster to market with your products you can spend your time developing your applications unique features instead of reinventing the wheel and enables you to write less code Coco keeps simple things simple and makes complex things possible it LO it raises the baseline for the code that you write so you're writing your applications unique portion in addition your application can automatically get new features over time without recompiling or reshipping thanks to the dynamic nature of objective-c and the cocoa runtime your application can take advantage of features as soon as they appear in the operating system they just automatically show up and so we've been talking a lot about the languages that are used up to this point so I want to focus in on that just a bit there are really two languages that are supported for croaker development objective c and java i'm sure you you all know what java is so i'll focus on objective-c here it's actually a language that was invented in the eighth in the 80s and is today a standard part of the free software foundation's GCC distribution and it's a very dynamic language and along with Java provides the support that cocoa needs in addition if you're writing in Cocoa you can plug in your carbon C or C++ code right into these languages or if you have UNIX code they integrate in as well so that still leaves the question open which language should you use and really the answer is use the language that fits your needs you may find that you have existing Java code or libraries that you want to take advantage of or you may have code out of the community that you want to take advantage of if so you may find that writing your application in Java using the cocoa api's is the best road for you on the other hand most developers find that the faster runtime performance and lower memory overhead of objective-c make it the language of choice will focus in on objective-c today with that I'd like to turn things over to my associate Tina to talk a little bit about some of the details of how you actually go about programming and coca thank you very much Matt once again my name is Tina flung and I am one of the hooker frameworks engineers so basically what I'll be talking to you about in this section is three things first we're going to cover some of the fundamentals of objective-c syntax then we're going to go over some of the various cocoa design patterns and finally we're going to talk about some of the various developer tools we have for you on the system so in order to illustrate some of these concepts we're going to take a look at this simple to do this example and in particular we're going to focus on adding a preference of pain to this to-do list and for those of you interested later on to the talk mass going to come back on stage and actually show you how you can integrate this preferences pane into a carbon application so let's just jump right in and take a look at Objective C syntax here's a copy of valid objective-c code here is a function that converts from Celsius to Fahrenheit and it probably looks very familiar to a lot of you well that is because Objective C is a strict superset of ansi c so all your old auntie c code from your old apps is still valid objective-c code so you don't always have to look at Objective C 3 answers however a deck to see does provide a few additions on top of an TC the first is we want to objective-c to be an object or have an object oriented there on top of 60 so this included having new syntax to define new types of classes and to actually deal with those different objects and most importantly one of the ability to send messages to these objects in Objective C one of the very unique things about it is we pass messages to objects rather than invoke methods and this means that the actual code that's executed is determined at runtime so in order to do this we needed new syntax to send messages and we needed run types runtime support for these messages and finally we needed various data types for these messages so let's just jump right in and look at some messaging syntax so for those of you familiar with any other object or any language like Java or C++ you might be used to a method call looking something like this so here you're sending a do something method to my object well an objective c each message begins an end with a set of square brackets to the right of the opening bracket you have the receiving object and to the right of that you'll see the do something message so here is a complete objective-c message now you can also have a message that takes any number of arguments so in a traditional optical anguish you would have something like this which is an ordered list of arguments now an objective-c we have something new that we refer to as name parameters so it looks something like this you begin once again with your receiving objects and then to the right of that we're going to have the do with this colon and this colon message the cones are part of the message name and to the right of that you will see the various parameters that you pass in and you have one parameter to the right of each colon so this is how you pass messages and objective-c now so leave me some of you may wonder why would we want to do this name parameters won't store this generally just improve the readability of your code in this case it's pretty obvious the two objects that you're trying to send but you can imagine a case where you have in this initializer that you're taking in 10 different arguments now granted the java method of just having 10 arguments in the list might seem shorter however you can imagine that you might start confusing which argument goes where and having the name parameters can actually be very useful so let's take a look once again at these messages but let's focus particularly on the parts in orange so the part of the message independent of the parameters is referred to as the selector of the message and you can actually programmatically access this part of the message using what we call the add selector syntax named a wonder why might I want this well this allows you to access a message independent of the receiving objects tight and what makes us really powerful is the fact that at runtime and compile time the type of the receiving object does not necessarily have to be known and this is because objective-c is a dynamically typed language the type of the object is actually determined at runtime and so we have the scenario i D object that could represent any object type and you're actually allowed to query the object at runtime and ask it what class it is and what methods are available to it and so you can actually use this message the response to select a message in order to find out first if an object does actually accept this message and then if it does send it the message so now that we've looked at some of the specifics of objective-c syntax let's step back a second and take a look at some generic cocoa design patterns and the first one that we want to talk about right now is memory management so Coco uses something called reference counting basically when you retain an object this increments your reference count when you release the object you decrement the count and we have something called auto releasing that decremented at some later point and an object is freed whenever the reference count drops to zero and so there are a few rules to the memory management contract the first being only creation methods and this is in it copy and you will actually return retained objects and in all other cases the receiver is responsible for retaining the object when the first gets it and releasing it when it's done and once again an object is deallocated once the retain count drops to then the remaining references and we can't retain count drops to zero so now we're going to look at another Coco specific design pattern and this is actually going to deal with communicating with the interface so you can imagine that in your interface you have some element in the UI and you want it to basically effect change on the application so first we're talking about that we use something called target action and so you can imagine you have a button in your application and the user clicks this button so what happens well essentially this sends a some sort of button clicks action message to whatever you're controlling object in your application is and we refer to this controlling object as the outlet of the action now in converse what if you have your application and you wanted to actually drive the UI and update changes in your interface well to do this we use something referred to as outlets so here we have the same controlling object as before in your application but you also have some sort of text field and you interface and essentially you want your controlling object to pass some sort of message to this text field and say steps the text field value to be whatever the string is and in order to do this you basically need a handle from your controlling objects that ties it to the text field and so in order to do this you set the text field as a controlling objects outlet so for many of you this whole communication with the interface may seem very reminiscent of something a general software design pattern called Model View controller so for those of you who don't have ever heard of this before multiple you controller essentially divided the application into three layers at the very bottom you have the model which is what stores and manipulates all your user data at the very top of it you would have the view which is everything the user see interacts with and somewhere in the middle is actually this controller which is the glue that ties the model and the view together and so to tie the fact with some of the earlier the early design patterns of target action and outlets I take a look once again at our button so the button is part of the view and when the button is clicked it sends the action message but that object that it would send the message to is referred to as the controlling object so that is your controller and this controller in turn would send a message to the model and tell to update so in this case it would tell the model while creating new folder and this is really important because as now you have the user interface isolated from the view and so you can make changes to your interface and not have to modify user interface and not follow your modify your model in return and vice versa and most of the application specific code is now isolated in the controller object and you can imagine the reverse of this is if something changes in the model and that would cause a message to be sent to your controlling object and then that would cause the you I'd update through the use of an outlet and in order to do this we actually have is really neat developer tool called in a base builder interface builder essentially allows you to have this easy quick drag and drop graphical manipulation of your UI and so it's very easy to develop your user interface to your application rather than unlike most other interface tools that essentially just write you out some source code to represent your view what interface builders does is actually very unique it archives live objects and also archives their connections and these connections are the target action connections and the outlet connections that we just referred to and finally it's completely integrated with cocoa from the day that Coco was built essentially we had interface builder and the two of them are built up together so it's not like we had this old developer tool we have this new like builder that just kind of does the same thing that writes more code it's really there to help you and make coding easier for you so in order to show you some of we want this now show you some of the coolness of interface builder so interface builder creates and archives your files in this nib format and so here's my project with my to-do list and I'm going to take a look at that file so here is basically a view of what is in your nib file and so you have your main window and various other properties in it that will go into in a little bit up here you'll see that there is your a palette of controls that you have available to you and finally we have the inspector window which allows you to see the different properties of your controls and so if you're trying to build something like this preferences pane you can start with like over here we have a text view and you can just drag it over here and notice that these blue grid lines drop up well these are basically guidelines to help you meet the aqua specifications so even if you have no idea how does how to design a few that meets apples criteria all you can do is follow these lines and you can make an app that looks like all other macs off apps and so now we can do the same by dragging out a check box and over here in the inspector window you can see there's a title and we can you can set the title to be from that Ike show completed items and you can drag it out to be whatever size you want you can just drag out some radio buttons and you can see here that you can change a number of rows and adjust it once again and notice how you do the Aqua guidelines they get to address is facing and you click on each of the items you can set the values and so we'll make that one red and we can make that one blue and we'll make this box and finally we'll add a button to the bottom and we'll tell this one to clear the to-do list and once again notice how easy it is to adjust your UI and so since interface builder actually deals with live objects you can do something that we've referred to from the file menu you can choose test interface and this actually lets you play with the interface as it would really work so you can see how the checkbox is checked and the radio buttons click and click on various buttons so now that we have our UI we need a controller object and interface builder actually allows you to do that so an undead File Viewer here we have a tab that shows clap the tab labeled classes and this essentially has all the objects that that nib file knows about so in this case is all of that kit objects and any objects that you specifically tell the nib about so we're going to subclass nsobject because that's the most basic of the objects and we hit enter it gives you a subclass and we can name it controller and here's a fresh controller object and I that shouldn't already be created but essentially here you have for your call my object here since I've apparently mess on my demo here and have trust control our victory instantiated so let's say you have an object called my object and in the inspector window you can see that you can create outlets and actions right here in interface builder so let's add some outlets so we want an outlet to represent the color buttons and we can add an outlet for the show completed button and finally we can add an outlet for the title field and you can do the same for actions so we'll have an action do clear the list and we'll have an action to set the color and finally an action to set whether or not you want to show completed items so once you have that then you can create the files for have interface builder create the outlines for outline template for these files so we look at my object and in the classes menu you can tell it to create files for my object and here I'll tell you you can choose to create both the header and the implementation file and tell it put it in my project now if you go back to project builder and look at it you'll see that it's created these two files for you so you take a look at them notice that no behavioral source code is generated for you and the advantage of this is really that once you create your view and your model you can actually just change the positionings of your view and change the way it behaves and not have to change your code necessarily and the same happens for your head header files and so let's go back to interface builder and so each nib file has to be loaded by some object of a particular class and by default its NF application but you can actually set this an interface builder through the files owner so every nib file has a file's owner and you can actually inventor in the inspector you can tell it sure made the custom class and as you can see this is NS application well in this case we're going to set to be my object and here it gives you a warning saying all yet that you're changing the files owner for men s application that's okay so now you have a way to essentially hook up your controller to your view so the way that that's done and once again remember the slide with the target in action you basically want to connect your control your controller to the items the controls in your UI and so for instance let's take a look at this clear to do list button and you essentially want that button to send an action to the controller object so you would hit ctrl and drag from that button to the controller object and you can say clear that that's action I want to happen and you stay connect and you can do the same for the various buttons here thank you tell the color button well I want this to set my color and the same with this checkbox control drag from that to the target which is your controller object and tell it to set the show completed now again the converse of that is what happens when you want your controller object to have access to your UI elements well you want your control object to be able to send messages to controls in your UI so you a control drag in that direction so you control drags from the controlling object to in almond it controlling the UI and you could say that is my set completed button to set that outlet and you can do the same for the color buttons and will want to set the title field and that's basically it's simple how easy it is to hook up from your UI to your controller object so for sake of time we're actually going to jump to a version that is already we've polished up the UI for you a bit and we have actual controller code implemented because obviously when that action message gets sent something has to happen and we're going to build and run that for you and high this and so here you can see if I go to file the demo and open up the preferences let's first create a few items like feed the dogs and call mom something and go get my lid on the Himalayas so you have these items and let's say that I remember to feed my dog and notice here that I can tell it whether or not I want it to show the completed button to complete a task and change the color of that and I can also clear the list I want so there's one more thing we want to do here and that is we want to be able to type in the to do list title and actually have it update in the to do list well using that target action pattern we can have some sort of apply button that will tell the title list to be set but there's a better way to do that because we want to have an actual live update from the preferences pane to the actual to-do list and let's actually go back to slide here in order to do this we use link virgenes delegation and this essentially allows an object to appoint another object to be its delegate so what a delegation well let's think of it in a non-coding fashion so yeah my boss and he's about to go on vacation so he essentially appoints Matt to be he says Matt I want you to be my delicate so all messages that would go to my boss will now go to Matt and so now I'm like I want to go on vacation and normally I would say hey can I deffenbaugh can I go on vacation but obviously he's not there so that message now gets forwarded to his delegate who in this case of matt and matt says Shirin tina's go on vacation because he's a good buddy of mine so this is delegation so in activity and Coco we actually have two basic behaviors that delicate can perform the first is the delicate can actually modify the default behavior of the object and the second is it can just be a receiver of notifications so whenever an object perform certain event the delicate can just be noted by that this event has occurred and so there are several classes in act hit that have a delegate outlets and when you set this delegate outlet its entity the dojo will be asked Hayes okay if I do this particular action or the delicate could just be notified that something has happened and so for instance if you have some sort of text field in this case zelig you may be asked questions like is this about about a ballad value for my text field and for instance if you want the text field to only accept numeric values you can adjust the behavior accordingly and another instance you can just want to know well the text is about to change and so the Dalek needs be notified that the tax is about to be changed and so essentially what this allows is you can customize a object without having subclasses so let's take a look at how this works so we're going to go back to a nib file close with one and if you look at the text the text fuel text view sorry notice that it has an outlet called a delegate outlet and so you can control drag from that text view to the files owner which is the press controller and say make this my delegates and Udall get set and so let's take a look at the code that was necessary that's necessary to make this change just take a look at the press controller and what you want to see here is the text did change delegate method and essentially this is called whenever the text changes and so here we're going to tell the title field set its font and set a string value and then update the window and so now if we build and run this that's too many windows here so now if you open the press pain when you change types of text so I guess ibises you know like my shopping list or something notice that it live updates on your to-do list and so a delegation is a very powerful basic design pattern that Coco allows you to do so there's one more thing we want to be able to set the spot of this to-do list and in order in order to do this we need something that's slightly different from this general target action design pattern that we've shown you up to this point and the main reason for this is well a font panel that you've probably seen for on OS 10 it can affect any number of views and so its targets essentially determined on the fly and so let's go back to slides here and so in order to do this we use something called the responder chain and this allows us to determine what our target is at any given moment and so the respondus chain is essentially an ordered list of objects that response to user events or event to general and this means that the target can be determined at runtime in particular the first object in this responder chain is referred to as the first responder and that's the actual object that were received the event and so the respondent chain is used in various places for example cut copy and paste you click on one text view and you say copy this text and then you click on some other text views from where else and you say paste and so first responder loud but to check what your main window is and determine that new view is where I want the tax be pasted also for menu item validation you can validate many items depending on where you're clicking and once again you can use this for things such as font panel and color panel and so let's show you how that works so essentially right now we're going to look at this other nib file which I haven't shown you up to this point but this essentially is the main window of your to-do list application clean out some of these windows so this is the main view of your application and in here though you'll notice that there's this main menu and this is essentially the menu bar that is associated with the application and so in your controls palette you have a bunch of menus they can add to it and in this case we're an ad as font menu and though it's good to have a whole like a ray of thing to get show the font panel bold underlining things like that so that's Avis and give it a run so notice here that we now have a font menu in our to do this application and you can just say show font and font panel comes up and so let's take a look at our preferences and so here's like I wouldn't say i want to emphasize that's my list so i can make the font really big probably a little bit too big Thank it so you smaller and I have no idea of what's happening this font sizes but let's make it all 36.5 but sent to HD here is that whatever view I've currently selected you can now have the font panel effect that particular view and that's because this text view here is the first responder can go back to slide please and so that's essentially cocoa in a nutshell you know we don't expect you to be full-fledged cocoa programmers by any means at this point but hopefully you have a general understanding of you know the various powers that cocoa provides and you will understand enough about cocos impacts to hopefully participate in some of the other talks that we have available for you later this week in the cocoa track and learn more about cocoa so I'm now going to pass this back to Matt to talk to you about how to integrate this preferences pane in a carbon context thanks Tina so this next part is actually one of my favorite parts about cocoa it's something I think is really cool and that's how you can integrate cocoa with other technologies now you can certainly use cocoa to build full-featured applications with mac OS 10 but a relatively newer development is the ability to integrate cocoa with carbon and even unix code you can mix cocoa code right in with your existing c and c++ code and we're going to show you how to do that today and why you would want to do it and then walk you through a demo so why mix carbon cocoa well there are three basic reasons first of all you may have existing code that you want to leverage and this is typically the most common reason for integrating carbon and cocoa there's an app that exists in carbon and you want to add some functionality using cocoa the second reason why you might want to do this is if you're writing a common service that perhaps applications written with carbon or cocoa could take advantage of for example the address book framework on Mac OS 10 actually bends api's in both see and objective-c for both of these frameworks and finally there may be various pieces of alternative functionality that you find easiest to access through one framework or the other and so you want to integrate those in one application so what does this involve well it basically involves just adding the code whether it's carbon or cocoa to the same source file go ahead and include carbon odd H or cocoa h we're both the other thing you'll want to do if you're including objective-c code in your existing C or C++ source files is change the file extension to dot M to indicate that objective-c code will be included if you're also including C++ in the same code you'll want to change the extension to dot mm to indicate that our other compiler the objective c++ compiler should be used this this technology allows all languages to coexist in the same source file and be compiled and if you have source files that you expect to be compiled on other platforms where perhaps objective-c doesn't exist and yet you want the code to just kind of go through smoothly you can use the pound if def abdi syntax and that basically says if this is defined then we're compiling using a compiler that understands objective-c and you can also force fit with the right compiler to be used on files without having to change the file extension if you choose so besides compiler support and source code support the operating system has support from mixing carbon cocoa as well vos itself provides what we call toll-free bridging of common data types between foundation in cocoa and the core foundation framework such data types as CF string and NF string can be simply cast to one one to the other in fact they're the same object and there are actually two main levels of integration between carbon and cocoa that we support priors and macalistair version 10.2 we supported non GUI integration so you could have for example carbon or causal code that dealt with the file system and then have the interface be designed using the other set of api's we change this in machynlleth 10 version 10.2 we now support mixing the graphical user interface on a per window basis which means you can have a carbon window in a Coco applications or a Coco window in a carbon application and the one thing to keep in mind is that you'll want to call this one function NS application load to initialize Coco if you're using cocoa within a carbon application so we've got a kind of nifty little demo here to show you guys you may be familiar with the glyph of three code base it's been around since nineteen eighty eight fifteen years was written by John Calhoun of glider Fame for the Macintosh and today it's fully carbonized and lives on sourceforge net where the source can be downloaded so let's show you this game we can switch to the demo machine Tina's going to create the start a new game it's basically a joust clone and the source code is available you basically sail around on your bird trying to knock sphinxes out of the air and i guess some sort of an Egyptian pyramid and she's going to try and get on the high score list here this code with Pascal black and white back in the day and then it was retrofitted to see in color and barest technologies were added over the years he was finally carbonized I remember playing this on my performance 633 megahertz back in the day so she's dive-bombing and into the lava it was actually a a mummy hand on the left hand side that comes up and grabs you if you're not effective so so here's a high score dialogue and actually given the history of this code base and it's pascal string and the string usage all we can enter english at this point we're going to retrofit this to be able to support more languages we could do this in carbon we're going to do it in cocoa we could imagine we want to add other technologies to this using cocoa down the road so she enters her name we get the high score list she's number one and now let's take a look at some of the architectural changes we're going to make to this so we could go back to slides please there are two things we're going to change we're going to add a preference panel you using cocoa similar to what Tina Illustrated earlier and then we're also going to change the high school name entry dialogue to be Coco so before the integration what does this code look like it's basically c6 source files it's straight see it includes a kind of basic sprite engine and sound engine it was something that John Calhoun actually used to learn how to program through the years as he was working all and glider for the Mac it includes high score list and other preference code it saves all these out manually using its own data structure which is end stores out we're going to change that a little bit we're going to go more towards the model-view-controller approach the Tina illustrated and access some of this through a preferences model instead of directly to distract and we've taken the liberty of making some carbon modifications to the code before stepping in with cocoa basically what we've done is replaced the pascal strings with CF strings to finally support Unicode in other languages this enables easy data transfer to NF strings as I mentioned earlier we can simply cast the CF string to an NS string or vice versa so let's go look at the other Coco changes we've made to discard the first thing to notice looking at the files here is that we've changed the extension on main from name see two main dot M this indicates that will be including objective-c source in this file and if we open it up we can look at the code that actually handles preferences when we load preferences we pound ifdef aab see this code just in case we would run a compile it on another platform I'm not quite sure why we want to do that here but it illustrates the point and what we can see is that we're calling NS application load to initialize cocoa and finally we create a new preps model object and initialize it with the Preferences data structure that glyph of three natively uses so that loads in preferences when the game starts up then when the Preferences menu item is chosen in the game we need to actually go and create this new Koko preferences panel once again we carefully conditional eyes our code and then what we call is NS bundles load nib named method and this actually takes a nib name as its parameter and basically loads up our preference panel which then displays on the screen let's take a look at that preferences panel now here it is this should look very similar to what Tina showed earlier and we've made just a couple of changes you'll notice a show fonts button here and what that's for is basically we can't add a font menu to a carbon resource manager based menu bar so we've added a font button here to actually show that font now other than that it's basically the same from a carbon perspective we don't have to know anything about how checkboxes and radio buttons are implemented all we need to do is write the code that gets run when these controls are triggered speaking of which let's go look at the set sound method now this code is fairly straightforward it basically gets the state of a check box and if it's on it turns on the sound if it's off it turns off the sound and then it synchronizes the model pretty simple now let's take a look at the other nib in this game that we've added which is our new high score entry dialogue and it looks very similar to the carbon one we showed before as it should so let's take a look at the code that loads this nib once again we allocate a new controller object and then call load nib named to actually load this high score entry dialogue so those are the changes we've made let's run the app now and see how this new retro fitted version of what 43 works so we actually have our preferences panel now which we can pull up so this is a Coco window running in a carbon application that's been around for 15 years we can go and change the name of the high score list we can pick a different font while we're at it let's pick something a little more Egyptian like papyrus or something make a little bigger maybe and sound is on so okay good let's close those windows and actually Tina will go and play a new game again download this sourceforge play it almost like I was pretty good at once she's made it to the high score list annoyed take care [Music] she has died at grew things happen and now she can enter her name but but we're not limited to English anymore we can actually have Tina go enter her name in Chinese thanks to the power of end-to-end unicode support through nsstring and see up string her name is displayed now in Chinese let's go back to slides so what have we learned today well we've learned that thanks to the object-oriented dynamic frameworks in cocoa your development can be faster we've also learned that the cocoa fundamentals really aren't that hard to learn an objective-c is is really not that bad and finally we've learned that you can integrate cocoa into your existing applications or build whole new applications using cocoa this point I'll turn things back over to Jason for wrap up thank you pretty cool stuff huh exogenous I think we have some really really cool stuff out there for you guys take a look at here's a road map of some of the sections of it coming up I've highlighted all of the cocoa sessions take a look at the cocoa updates see some of the really cool stuff we've added you may be new to cocoa but we've done some great stuff with it we've had some really cool user interface stuff that we've added also some nice 2d drawing techniques for those of you who are into the graphics out of stuff we actually don't have a cocoa performance techniques anymore we replaced that with an in-depth session for the cocoa user interface some nice tips and tricks to show you how we've taken care of some of the iTunes ichat kind of stuff you see the really nice things that Apple's done with its applications and other people have done with their applications and of course the feedback forum if you like cocoa and I think you will after this week be sure to come by and say how much you like it and if you don't you should say that also so we can make it better and if you want to send us some feedback John girl NZ's the manager of software evangelism he is the person who's responsible for making sure the stuff that you guys need in cocoa gets into cocoa so make sure you send an email galamsey at apple com if you've got feedback on the api's you start using them that feedback should go to cocoa feedback at grupo apple com goes directly to the engineering manager responsible for building cocoa and if you've got technical questions you should send it to my group develop a technical support when we will help you as best as we can to answer those questions without a lot of great resources on the web in fact you can go up there for some more information we've got documentation on cocoa the entire API set is up there tutorial sample code you can download lots of really great stuff some really good books are out there also our partner partnership with O'Reilly which has benefited all of us by giving you a free book if you haven't already gone and gotten it I'd go down and get it it's the cocoa nut shells the fantastic introduction and intermediate level books for cocoa developers absolutely go pick that up it's in your bag get that and there's a couple other things also so in wrap-up thank you all for being here I appreciate your time I'd love to have you stick around for questions but but we don't have an official QA but we'll be happy to answer any questions for you now or in the DTS lounge on the first