---
title: WWDC2003 Session 415
framework: wwdc
role: article
path: wwdc/wwdc2003-415
---

# WWDC2003 Session 415

## Transcript

Kind: captions Language: en data exchange so what do we mean by data exchange as avi i mentioned we're talking about in today's mac OS 10 and and earlier mac OS some technologies such as the scrap manager which we've had since 1984 for doing data exchange moving data between applications on the clipboard a few years later we introduced the drag manager which is similar api many ways for moving data between applications but through drag gestures we're also talking today about the translation manager which was also introduced several years ago and integrated into scrap and drag so that translations can be performed somewhat automatically when moving data between applications and all of these technologies are based on OS type data identifiers for character data identifiers and all of these technologies have served us very well we've made a lot of strides and user interface in making it easy for users to move their data between applications but there are also some limitations some problems that we would like to get past going forward we have a lot of ideas for enhancing the user experience and being able to make classifications work together more seamlessly and we were bumping up against some problems one is just that the scrap manager and the drag manager although they have a lot in common for marshaling a bunch of data together to move to another application their separate API and so if you want to support the clipboard you do one thing when you want to add drag and drop support you have a whole other similar API that you also have to adopt so kind of double the work for you with Trent with the translation manager it's kind of a difficult API to use the model isn't really quite what we want for data translation it's handled based so it doesn't really work with core foundation collections and so on which make memory management much easier so translation just isn't isn't really working quite right and then finally the whole issue of type identification as i said the carbon technologies tend to be OS tight based coco uses strings and NS and it's pasteboard use of strings for data identifiers and then there's also mine types coming in over the internet there's filename extensions all these different ways of identifying types and there's a number of issues of that that we'd like to resolve so what are the solutions that we're going to be talking about today first one is the carbon face board this is a new technology new API which is a complete replacement for the scrap manager and also a replacement for large pieces of the drag manager so it unifies that data model for moving data around between apps and then there's a new API called translation services which is integrated into the carbon paste board and improves the translation architecture to make it easier and faster to work with when you're developing your applications and underneath those technology those technologies that something we're calling uniform type identifier which is a new way to describe type information and gives a very rich model for managing type information and it's a foundation both for translation and pasteboard as well as future technologies that we're hoping to introduce so since it's really the foundation we're going to talk about uniform type identifiers first and then later on my colleague Brian Fisher will come up and talk about carbon paste boarding translation so in order to help you kind of understand the concepts of uniform type identification I want to start with an example of I just picked the type tip tip images how do we know what a tiff images what is what's the tip I'm not talking about what's the format but how do we identify chips and the first one you might see is the OS type T iff that's what a lot of carbon apps would work with that they were putting TIFF data on the scrap but there's also a mime type so an image coming in or with the internet would have the image / tip mimetype there also happens to be a filename extension dot t iff there's another file name extension gif which you have to reckon your app working with tiff data or tip files has to also recognize that filename extension and then data put on the pasteboard by coco applications would use a string and asked if keyboard type so there's kind of this whole cloud of type identifiers and currently on Mac OS 10 in previous Mac OS SE the only facility really for tying these together at all was internet config which was very internet oriented and its API is also pretty fixed in terms of the tight spaces that supports for instance it doesn't understand anything about and if pasteboard types and so we were trying to think well we really need a way to talk about types we need applications to communicate about type information by passing type descriptors around we need type information expressed in bundle property lists and we want want it to be easy to indicate what kinds of documents and data your app can work with and so we need a good descriptor for types and these type spaces all have various limitations OS types work great for the ones that we're very familiar with but we're pretty limited by four characters they're not very descriptive and so if you see some third-party OS type with four characters there it's extremely cryptic you have no idea what that data type is and furthermore it's there's really not really much collision protection toro it and for new OS types similarly corresponding expenses are mess there's no collision protection is all there well they're not a complete mess but there are some some collisions there to file our filename extension meaning two different things and although mine types are a little bit better because they have a registry in order to avoid duplicate or reuse of a line type string the registry turns out to be not used a whole lot there's extensive use of the X dash experimental space in line types and if in in addition people will use the mind types as very the Creator X Dash mind type and and then later on they might register the same mind type without the X Dash and so there's multiple mime types that actually mean the same thing and so we kind of wanted to normalize all of this and come up with a name space that could tie all these together and make sense of type management on Mac OS 10 and in the example here the identifiers that we're talking about is public tip and this is the uniform type of diner fire for the tip data type and I like to think of uniform type identifiers as the one true name for it for the type on the system and to use kind of a literary analogy it's sort of the one name to one name to rule them one name to find them one name to bring them all and in the darkness finds them because not only does the uniform talk identifier identify the chip type but it makes the API makes it very easy to discover all of the other type descriptors for this type and so it's kind of the Nexus 4 type description so what about that public thing upfront well unlike mime types you know from type of identifiers don't actually they don't actually express any sort of type hierarchy in the name so the prefix on any type identifier is in general a reverse dns name we're reusing the reverse dns naming convention that in use in several places on mac OS x such as in bundle identifier so type identifiers from that our proprietary or associated with a particular organization are prefixed with that organizations reverse domain space however there's a lot of types that really aren't owned by any particular organization and those go in the public domain which is at this point controlled by Apple I encourage you not to use the public domain and let us put things into the public domain now because of the naming convention I mean you know from taco ten car really is just a string and and the format is a naming convention that we're asking everyone to use if you follow the naming convention you're pretty much guaranteed and not conflict with anybody else a and B it's a very descriptive string for what the type is it tells you not only at the end it described can describe something about the type but it indicates what organization actually owns and defines that type and so it gives you as a developer when you see some uniform type identifier coming at you from another application you have an idea of where to go to learn more about that type throughout the rest of the talk we might be referring to them as UTI uniform type identifiers that's the abbreviation so what are some examples in addition to public tip another one is a little more verbose public dot UTF plain text so it's an example of a very descriptive type you can pretty much look at that and figure out what it is it's a Unicode utf-16 encoded chunk of plain text in fact this is the type that we encourage everyone to start using with the carbon paste board when you are sending plain text to another application here's an example picked a quick drop-kicked is something that is specific to apple and so we put it in the common space and adobe might they they haven't done this but just as an example they might for photoshop documents use condotta dobie PSP or they might use something more for both like photoshop document so in addition to describing identifying types specifically there's something else which the system has never done before to model our understanding of types that we all have as developers in his users which is what else do we know about a tiff as humans we know that it's an image and we know that it's a chunk of data and what the uniform type identification system does is allow types to exist in a conformance hierarchy we can we can declare types as conforming to super types so that even if your app doesn't know anything about a very specific type of you receive you can discover that oh this type is actually a form of text or it's a form or it's an image and that example was somewhat trivial but a somewhat more interesting example is receiving something that I'm not even going to pronounce because every time I did during rehearsals I sounded silly but this is an example of something you have no idea what it is and it arrives in your application through a drag gesture say and you would think you can't do anything with it but if you happen to be an XML parser you can say is this type XML and it turns out it does conform to XML or is it even generic text and you can discover from by asking the system that it does conform to text and so you can actually work with this data even though you don't know that complete specifics of its format so in those last few slides then I just outlined all the major goals of uniform type identifiers to tie together all the disparate type identifiers spaces model conformance between types enable extensibility through new third party type declarations without needing registry or any sort of having to worry about collisions and in support of all that just provide a very simple lightweight API which is a foundation for any component or code that needs to do type management so now I likely go back and just go through the same concepts with a little more deep about some of the API behind this when we talked about OS types and mime types and extensions and NS pasteboard types we needed a word to describe all of that so we just kind of fix this one tags what we have all that cloud of blue identifies are all tags that are related to a particular uniform type identifier and each tag has a class the classes indicates if it's an OS type or a filename extension or a mime type etc and the thing to remember about tags is that it's not always a one-to-one mapping usually there's a one-to-one mapping but not always and so some cases are complex you have to map multiple filename extensions back to the same uniform type identifier sometimes the same extension or os os type may have a collision in may map to two different type identifiers so our API makes it easy to deal with the common case of a one-to-one mapping but it also allows you to enumerate all the different combinations so that you can discover more complex type relationships so here's here's that cloud again of types and the API lets you easily map between the tags around the outside and the one true type identifier in the middle and so that makes it very easy to go through kind of a two-step translation where you you get to the uniform type of inner fire and then you want to know what the tag is in another space and you can go from there to the tag and this this is actually used probably more heavily in the system than you may have to use it because we have to deal with co collapse and filename extensions in in the file dialogs and os types in the scrap manager and we need to make all those systems work together especially moving between moving data between the NS pasteboard and the scrap manager and so we rely on this internally to do all of our mapping between namespaces and how do we do that very simple this is just a trivial example of taking the OS type jpg which is treated as string in the API and you call UT type create preferred identifier for tag you passing the tag information you say that it's an OS type tag and you get back the type identifier 4.jpg which happens to be public jpg then if you want to go to the mime type for that you would just do another it's another string operation UT type copy preferred tag with class and you say you want the mime type class and you get back the string which is image / jpg so it's a very simple mapping process now on to the conformance model and testing types for equality so this is a just a simple hierarchy of type identifiers we've got HTML and XML as generic text types in an XML includes combat Ethel dot property list on your right and XHTML is a subtype of of XML and let's say you're receiving some data from another application and you there it is you handle XML you're at some sort of XML processor you want to find out if the data is is XML you can ask does the data that I'm receiving conform to xml and if that if the type identifier that you're receiving is XHTML or com Apple plist or just plain XML then you get back the answer yes this is data that I can deal with in other contexts you actually would you want to test for specific equality of types of the type information and we provide an API for that which fundamentally uses a string comparison to do the Equality but there are cases where a string comparison isn't enough here are those api's again very simple just to input strings returns a boolean and I wanted to say a little bit more about why the equal why the Equality test is there obviously to do conformance testing you have to result for resort to calling that so that we can use the type information in our database to give you the right answer as for equality well we do use the string comparison internally to test equality its case insensitive since these are like DNS names UTIs are all case insensitive but we also expect in the future that you know as carefully as we try to design the naming conventions for types we're expecting that little warts will happen there will be a type identifier which is in somebody's or some organizations domain and somebody else will put it in the public domain or Apple will want it in the public domain and if you use this API to test for conformance and equality will be able to do things like declare to type identifiers of synonyms and everyone will just continue to work if you use our API so I want to talk a little bit about declaring new types and then why go into the details but there are some samples I can point you at so new type identifiers are declared in bundle property lists in your applications bundle property lists in fact all of our built-in identifiers are declared in the currently anyway in the seed in system icons bundle down in system library core services so you can go there to find an example it's very similar to though if you're familiar with declaring document types in your plist declaring the types of documents you can open it's very similar to that we've kind of taken that idea and abstracted it out to just deal with type information so that you can declare in your pee list what your type identifier is that you want to use and what the equivalent tags are so you can associate it with mine types and filename extensions as well as what it conforms to is it an image is it text or something more specific and once you do that and your app becomes registered on the system we we add that type information to our database and it's available globally so that when you send your data to another application with your specific type of identifiers to it that application can use our API to discover things about your data the last thing I want to say about it was that there's actually two ways to declare a type one is called exported and one is imported it's a little subtle but its necessary in general for any type identify earth at you are giving out to the world for your your data type you export it from your property list you make an exported declaration in for in if you're using a built-in type such as any of the public types then you can rely on that always being declared in the system because the OS guarantees that it's there but sometimes your apps might depend on some third-party types that has been declared in oh say a Microsoft Application you want to import Word documents and Microsoft has declared in their property with their bundle Microsoft Word identifier and you depend on that declaration and you depend on the system knowing about that UTI but you don't know if Microsoft Word is installed on the system you're running on in fact you probably hope it isn't installed because you want to read those files and provide services for importing Microsoft Word documents so in that case you can actually read eclair Microsoft's definition or declaration of their type and that's called importing and you say i'm importing this type declaration which really tells us that you're not the definitive owner of that type and if if word is installed or the third party app is installed will use their declaration but if you want to ensure that a declaration is there then you can use that style of importing so that is really an overview I didn't I didn't cover all the API as I said there's there's additional functions for dealing with ambiguities in mapping between different types but and so it's a conceptual overview and what are the guidelines for working with these again we provide tests especially when working with pasteboard data and drag data you want to use those these new api's use uniform type identifiers until you want to use the conformance and equality test when receiving data to find out if its data that you can accept wherever possible use the built-in types that we're providing and when you do need to declare new types just make sure you pick an identifier that's in your organization's domain space so that you're guaranteed as long as you're your own or because organization is coordinating within itself you're guaranteed to have a unique identifier for your data this is all implemented as essentially an extension of the launch services database and so at this in the seed anyway the API and extensive commentary and documentation lives in launch services H it's likely to get its own header file before we go GM but that's where you can look in the seed for more information so that is the foundation for tight management and this brings us to Brian's part of the talk where it will talk about how the carbon pasteboard leverages type identification all right thank you Chris Chris has just played a great foundation for these two new API with uniform type identification now I'd like to introduce the carbon paste board and translation services which will leverage this foundation first I want to talk about data exchange today a little bit more as you meant as Chris mentioned earlier we have separate scrap and drag managers they do basically the same thing you put information on a scrap or drag in one application you pull it off another application this is a little redundant this not only means that you have to pay attention to two api's then you have to do twice the work in your app if you have twice the amount of code and these involve different models the scrap manager only has a single item drag manager has multiple items the way that you provide data or provide promises and fulfill promises are different so you don't have so it's really kind of a pain to keep in mind which model year in also as Chris mentioned there's a limited typing mechanism they're both based on OS type and you can have collisions you need to contact apple and make sure that you register your types and this is difficult and something we wanted to move away from and currently there's pretty much non-existent communication with Coco you might think well I can copy and paste between Coco and certainly they can communicate but this is something that's handled by us internally we only do it for a few standard text and picture types and so there's really no way for a an OS type based API to communicate with a string bass Coco API and the memory model is fairly labor labor intensive what I mean by this is that when you want to pull information off of a scrap or drag you have to ask for you asked how large the information is and then once you have that create your own memory then ask for that member do this field be filled in and then release that later so we wanted to get away from each of these issues now the solution to that is the carbon pasteboard the carving paid sport is the unification of the scrap and drag flavor API so it's a complete replacement and you can move away from them today the carbon paste board supports copy and paste drag-and-drop and services both Apple menu services and translation filter services which I'll get into later we really like the model of having multiple items each with their own set of flavors that the drag manager has we think this is very flexible and we wanted to bring that forward and flavor tape types are now based on uniform type identifiers one great thing for for scrap and drag means that because it's based on UT is you can now communicate with a netpage board type Coco types will be added onto the page board you know convert it into UTI and then you can pull them off as uniform type identifiers and then convert them into any type you like using the ETI API and the pasteboard carbon page for disc or foundation based the pasteboard reference itself is the core foundation types and so you want to use the you wanna release them after you've created them but the entire throughout the API is based on core foundations vlcc of strings dictionaries and data alright let's talk about the base type that you'll be dealing with with baseboard the page board a page board reference is a proxy to a global pasteboard resource you can have multiple references a reference in multiple applications to a single global pasteboard that's kind of the point so you can communicate between the two you can have multiple references within a single application so if you have multiple objects within your application each one of them could have a local page for draft as the number of references on the system within multiple applications increases the rest count on the global pasteboard resource increases and so as each of the references are released to CF release then the references on the global page for release once the last application has released its reference the global page board memory goes away now there are two exceptions of this well which I'll mention in a moment now that we know what a page flow references how do you create it one well you can call pasteboard create they're created by name and there are three ways to do this first its use to standard names either k pasteboard clipboard or k pasteboard find the clipboard is the standard copy paste clipboard that you're all used to and you can keep using that for copy and paste operations the sign pasteboard is relatively new we brought this over this an idea from coco if your if you've ever been in project builder and you've performed a search through your code maybe there's some output you wanted to search for like you know printf statement and then you can go to terminal or console and perform the same search without having the types of text and again that's because as soon as you execute the search in project builder or now Xcode that information is added to define pasteboard you go over to lend me a flick one of the other applications perform the same search it'll read the information from the find pasteboard this is one of my personal favorite features I use it all the time and I really hope you guys all take advantage of it the second way to create baseboard is to create a unique baseboard you can pass either null to baseboard create or the K pasteboard unique constant and this is a way to make sure that you're creating a pasteboard that no one else has referenced yet no one else has access to it's completely new you can fill it up with your own data and it's ready to go the third way is to create a custom baseboards so since they're created by name we want to encourage that you use a reverse dns scheme so you're not running in anybody else's face boards so this is the way if you have a suite of applications or if you have the suite of applications and you want to communicate between all of them they can agree ahead of time and what name they're going to use making all references page the single pasteboard perhaps you have a multiple processor machining and you have a series of separate apps that you want to send marching instructions out to if you continue to get on the face board for instance alright now that we've created a pasteboard want to access that page board to do certain operations with it typically reading or writing the first thing I'm going to talk about is reading from the pasteboard before you want to read from the pasteboard you want to check out and see if any other applications has modified it so you can call pasteboard synchronize which returns to the flag indicating whether the page sport has been modified so if you're some other applications in the fronds lee the user has performed a copy your applications been brought to the front and you're curious as to whether you want to enable paste or not you can call pasteboard synchronize on the clipboard the clipboard baseboard and and it will return to the flags indicating whether it's been modified or not if it has then you can go ahead and look at the pasteboard see if there any tasty flavors on there if so go ahead and enable your pace item paste when you item now if you're going to write new information to a page board you want to make sure that you clear it first clearing the page floor wipes out any data that any other application has written to it and makes your application the owner so you are the only one who can write to it at that time so the tool to rules here are always think of pasteboard for reading data from it and always clear the pace forward before writing to it all right there are two branches I could take at this point either writing or reading data I'm going to take the reading data branch first so when you're receiving items or when you're receiving Gator from the pasteboard page report has multiple items and so you want to get the number of items through pasteboard get item count and then we access each of the items through a unique identifier doesn't matter what the identifier is it could be you know one two three indices or it could be a pointer to your memory in your data in memory this is actually very similar to the way drag manager works today with multiple items so for use to that model most of you should have some grad code or copy and paste code in your application so a lot of this will look very familiar ok once you've looked at the first item you can enumerate the item you want to look at all the flavors that are inside so unlike the drag manager which required you to not only iterate through each of the items but then iterate for each of the flavors will pass all the flavors to you it wants from a single API pasteboard copy Adam flavors it passes back a core foundation array each of the each of the types on the page board are uniform type identifiers so you'll want to make sure to use the comparison routines especially when you're when you're reading the data especially conformant ask for the data in a general way as possible if you're a general text editor first you want to ask it can I handle or is text available on the pasteboard and then you could be more specific after that if you like one important thing to notice translations are back with translation services and the translation now translations are always offered after the sender flavors so ordering when the ordering is important when pulling flavors off the baseboard when you're done with the flavor array you'll want to release it okay now you've got a bunch of these flavors but you want some more rich metadata associated with these flavors so you can grab the flavor flag to be a pasteboard get item flavors like now these are almost exactly the same set of flags available in drag manager today this is for compatibility with one exception the there's a request only flag now that behaves very similarly to the sender only flag of yesterday it behaves a little like having an unlisted phone number so so somebody trolling through the phone book can't find your phone number but if you share it with your friends then you can call each other and so this is very nice if you have a suite of applications and you want to communicate between them but you don't really want to announce certain data types out to the world and so any any flavor that you add to the pasteboard that has a request only flag set on it will not be advertised in the previous API that returns all the flavors on the pasteboard but if you know that if you know the flavor name you can go ahead and ask for it explicitly and then get it flags and get the data so this is a nice addition that I think you'll appreciate ok once you've looked at all the flavor flags you can look at the flavors paid attention they're ordering there's a rich amount of information there that you want to pay attention to but you've decided you've got the flavor that's right for you and you want to get that data a single API you want we want to deal with at this point is pasteboard copy items flavor data again it's based on CS data and so you'll want to release the memory when you're done with it but now you don't have to do when you okay you don't have to ask how big the flavor is very simple ok now let's back up a little bit i mentioned that other two branches we could take let's go down the other branch where we can add information to baseboard when you add data first thing you want to do is add data in your applications order of preference in richness now that seems a little odd you think you want to add it in the order of richness seta a receiving app would prefer but really when you're initiating a drag or putting information on the page board for a copy there's no way to know what the receiver is going to be and so you can't anticipate what order they will want the information in so the the best thing you can do is indicate this by adding information in your applications order richness as justification saying you might want to look at this item first in order to add a promise you can pass null as the data or the que pase Ford promise data constant now this is very convenient there's just one way to add data one way to add promises there's no longer two separate models between scrap and drag once you add data you want to fulfill this in a promise keeper so keeping promises you all wait you you have to install a promise keeper before making promises the carbons pasteboard make sure that you are able to fulfill the promises that you add because it wants to guarantee that receivers of that information can get access to it in order to keep the promise some application has requested that your promise be fulfilled and your pasteboard promise keeper proc will be called back you'll be given the pasteboard that the promise was made on the item that was made within and the flavor type being requested and any contact information that you've passed through so when the promise we can be kept just called pace flow put item flavor data as if you were not making promise to begin with very simple again it's just a single API for adding data and fulfilling promises so promises one cool thing here is that promises are resolved when you release your page for graph so if you have again a plug-in architecture in each one of your plugins has its own pasteboard reference and they can each make promises to the global pasteboard independently of the others and so if one plug-in is brought in to memory it adds a promise to the pace board but for some reason it's going to be moved out you know you're dropping that plug-in then when it releases the pasteboard only its promises will be explicitly called in all the others will remain so this is a great way to a lot of promises in a plug-in architecture all right I mentioned that this is a replacement for the drag flavor API there are a couple additions to the drag manager you can see some header doc on them in drag th in a tie toolbox you can use the pasteboard with dragon in two ways either create a drag and pull the pasteboard out of it this is useful if you're receiving a drag and you want to use the pasteboard api then you can just when you're given the dry graph pull the pasteboard out of it or depending on your the flow of your application if you are using the same code to perform copy paste and drag and drop maybe you have a pasteboard that exists already and so you can call new drag with spaceport and a new drag will be created with the pasteboard that you've provided alright a couple guidelines now for using the pasteboard carbon pasteboard always pay attention to the flavor flags and ordering if you're receiving information you want to take advantage of all the information that you have to choose the right flavor we've had issues when trying to add some default translations that applications will see a translated flavor and think that that's the one they want to make it in context and in fact the context that you'd be pasting your dragon 2 might not even be applicable for that type so it's very important to take all the information that you have and make the best decision you can always use UTI comparisons for the best results you want to leverage that API to get the most covered you can in receiving data one note about the wwc feed is that NS pasteboard types are added by coco ads and its base flow types they're not yet converted to you form type identifiers their existence is only temporary they will be going away they will be converted to uniform type identifiers before panthers ships so i don't want you to see them and depend on them so pay attention about being there this will change for Panther and again there's plenty of header documentation in pasteboard eh this is located in h services in the application services framework there's header doc there there's a couple features that I wasn't able to get into here go check it out for details also there's some sample code that we whipped up for the conference pasteboard picker it's kind of a cool little sort of text editing app that shows you everything that is on the drag or in the pasteboard you can add information to the to drag or pasteboard and it exercises the API and shows you how you can use it that's on the ATT member site go check it out all right that's the carbon paste board let's get on to new translation services thank you translation let's talk about translation the waiter today again they're a set of problems that we've discovered and we really wanted to solve these again there's a limited typing mechanism with four character for character codes OS types and we've gone over this several times it's also a legacy API for instance based on FS specs which they have no unicorn unicode support and so we couldn't support the full type of full number of those files that we want to support on Mac OS 10 today in fact it with the memory models still based on handles and it's still based on C arrays of all things you know if you if you wanted to get some information in an array back from the translation manager you'd have to pass through a CRA and if you didn't allocate enough space to bad if it wanted to give you more information than you had asked for and the third thing is really one of the biggest things is that the way to extend translations in Mac OS 9 and earlier the plugin mechanism was based on extensions and extension simply don't exist in Mac OS 10 today and so this is an issue that really needed to be resolved in the solution translate some services so translation services is the successor to the translation manager the source and destination types are both provided as uniform type identifiers so very flexible it's accessible via filter services which I mentioned earlier this is something else actually we've adopted from coco they're very similar to Apple many services with a modified plist and I'll get into that later and the entire API again is core foundation base so it an advanced memory model so a translation reference a translation references the base type will be dealing with it's a proxy to a resource on the system that translates data from one format to another it contains all the information that's required to perform a translation to sort the source types that handle the destination type that will provide and whether it handles file or file or data translations and in the translation services model translation discovery and execution are separated and so that's that's important because you can create a translation if you know you're going to be referencing that translation many times and finds like a mini files or something for instance you can hold on to that because it's the CF types can throw it in a CF array or dictionary and keep it around so later let's talk about discovery translation create translation created is a pretty simple straightforward API for finding translation you might need you to say you have a source file you have you know point a here and you want to get to point B you know what you know that there's a destination you want to get too does the translation exist that supports step so you can hand the source type the destination type and searching for data and file translations I perform through the same API now and so you can pass through the translation flags whether you want a translation that handles just data just files or maybe both and then if the resource exists that performs its translation the translation references handed back to you so that looks for very simple needs if you have more details or complex discovery need you can use translation create with sorcery it will handle any permutation of translation discovery that you need given an array of source types it will provide to you all the possible destinations that can be generated from the source types and a dictionary of translation reps which perform those translations the translation dictionary of translation rest is keyed by the destination types and so it's easy to look up again when you decide on the translation that's right for you you need to release the CF array and the CF dictionary now how do you discover which translates out of all the translations which one is the right one for you well you can easily translation accesses you can you have access to the source type the destination types and the translate and flags it support we hope to add more accessors in the future for when more information is provided this is the way you can go through your side that I really want to get to this to this destination type and you really want to get to one destination type but I prefer it coming from this source than this works because it may be this one's a little bit richer if you really get fine details if you want to alright you've discovered translation you've created it you've got on your hot little hand and you want to now perform a translation you want executed translation so if you want to perform a data translation you can call translation perform for data hand it the translation rest hand at your source data as a CF data and then the CF eight arrests will be given back to you holding the destination data you know read that data out do whatever you want with it and then release it that a couple things you need to pay attention to make sure that when you're handing a translation rest to translation perform for data that it actually handles data translation otherwise you'll receive an error immediately also something that you want to make sure is that the source and destination types in the translation ref are the same source and destination that you're providing and expecting from this API and very similar for translating files call translation perform for file after the translation ref your source file you can provide the destination directory and named for the destination file and then the API will return an fsr of your translated file and again you need to make sure that the translation have to force files that you have the correct to the correct source and destination types if your application happens to not be FS rest base or the translation code is not FS rest base you can use the URL API currently only file URLs are supported and again when you receive the data back we need to receive the URL to your translated file release the fury CF URL reference alright I've mentioned filton services a couple times along the way these are the extension mechanism for the default translations these are very similar to Apple's service ethel many services with a modified p list so if you've written one of those be very familiar I don't want to get into too much detail here the page boards the pasteboard peaker sample again that I mentioned earlier about the bottom this slide has an example for you but when you're going to perform it you're going to perform a translation your services launched if necessary if it's not already running the source say that is delivered to you on a pasteboard you can pull that data off to form a translation and then put the destination data back on the pasteboard hand it back and the client can have that have access to that data all right a couple guidelines for translation services you translate create for very simple needs if you have one or two types that you're interested in for given source types you can just call it a couple times and ask does it handle this flavor doesn't can I get this flavor can I get that flavor oh I can get this one great if you have more complex needs than that called translation create with sorcery and again it'll handle any permutations you have definitely check out translation services eh header for details lots of header doc there again some more lots of examples there for how to create a translation service and so on so go check it out NHS services in the application services framework all right in summary we come up with three great new api's that i think will i know they definitely helped us internally and we're really hoping that they'll be great for you what we need to do now is you know you've got the season your hands get to work uniform one type of dental fires are a really flexible framework for typing if you if you have data that you need to type it's the way to go always declare new types in your internet domain so that if there are your type you own them otherwise import them from other applications and always use the ETI api for conformance test this is your mantra because you want to make sure that you can really leverage the full flexibility of the uniform type identification API make pasteboards can really streamline your scrap and drag you said you know I was coming up with that pace that pasteboard paper Peter sample and it was it was really cool just how simple i could use the same the same function to read data from both drag and copies and the same function to add formation to drag the copy really convenient now that you have access to UTIs to local applications look at coco applications that your apps might be able to correspond with and really see how you can leverage coco app usage and then always be aware of automatic translations they're there to help you but make sure that they're not getting in your way is make sure that you're looking at the flags as you see whether it's a translation or not and decide whether you want to have a translation or not and a piece of translation services translation manager is frankly unimplemented on on 10 we wanted to make it happen but because the reasons I stated earlier I knew that we could perform or create a much better solution for you and useful for services to extend the default translations there's only a limited set that apple will be able to provide there was a really rich set of translations available in the mac OS 9 world we really like to see those brought forward to mac OS 10 so check this out this is excellent third-party opportunity for all of you so with that I'd like to bring Xavi a backup for the wrap-up thank you okay okay quickly the road map before we go to the Q&A session for night eh I two books was Wednesday some of you can travel in time I encourage you to get that session it was pretty good and if not we'll have it on DVD using the apple trees for cover and development same shame that was just before but Apple has been investing a lot of time and effort in Xcode and then encourage you as well to like check it out you won't have to travel in time to see session for 16 which is optimizing performance on presidio it's a great great session for anybody that is doing C and C++ develop milano platform we're going to be going to like a tonne of information we're going to give you like ideas on how to improve performance on your app please join us this afternoon and tomorrow of course if you haven't heard you know we have a brand new h-hi toolbox available in Mac OS 10 since 10.2 we introduce a chive you and should you need more information on this great energy please join us tomorrow afternoon all right should she did you change that you still fired you are so fired anyway which is that later should you have any questions on the new place both services please send me an email and we try to get you going it's very important to understand that you know the idea here is we need to have your feedback so please check out the api's and contact us should you have any specific needs or maybe we forget something or like maybe there's a special case to make you like you know around that you know we need to implement and that but the idea with like you know having wdc and giving you the state of painter you