TweetFollow Us on Twitter

The Web from Cocoa

Volume Number: 19 (2003)
Issue Number: 2
Column Tag: Cocoa Development

The Web from Cocoa

Integrating web content with desktop applications, Part 1 in a series

by Fritz Anderson

Introduction

More and more information is available through the World-Wide Web, and more and more computers are constantly connected to the Web. The public Internet aside, private intranets host HTTP servers to make corporate information available in-house. The problem with information presented on a web page is that once on the screen, it has reached a dead end: It has been formatted and presented for human consumption, and unless a human intervenes to copy it, the information will go no further. Often, you want to bring web content into an application so it can do further work.

One solution to this problem is the use of remote-procedure-call (RPC) protocols like SOAP and XML-RPC, whereby information providers supply computed or stored answers to queries submitted in a simple language. This is the ideal solution, because both provider and client have agreed on what service is on offer, on how to ask for it, and on how the result is formatted. It works especially well when both provider and client are "on the same team"--for instance, working on the client and server ends of a single system.

But there are always going to be information providers that don't offer RPC interfaces. A provider, for instance, might have a budget and a mandate to make its information public, but not enough of a budget to do the extra development needed to take its system beyond web service. There will always be a need for programs that retrieve web pages and process the results.

Road Map

This series will take you through two simple projects that explore the two ways a web client requests pages from a server, GET and POST. GET queries are simple, and built into many of the classes in the Cocoa framework; in this article we'll see how it's possible to do a rough-and-ready fetch in just a few lines. We can take advantage of the ease of making GET queries to put effort into making the user experience better.

POST queries are a little trickier, as there is no support for them built into Cocoa. Apple has, however, provided powerful tools to make up for it, in the Core Foundation framework, the procedural layer that underlies both Cocoa and Carbon. Many Cocoa programmers are chary of getting into Core Foundation, and that's a shame, because while there is a slight learning hump to overcome at first, the rewards are great. The remaining two articles will focus on getting over that hump, and packaging a simple POST facility in a Cocoa wrapper.

Thomas: Our Example

My introduction to page-scraping came in my project Jefferson, an application to put a Cocoa face on the Library of Congress's legislative-history database Thomas. Located at http://thomas.loc.gov/, Thomas is a comprehensive, well-indexed compendium of summaries of every bill considered in Congress over the past three decades. A variety of queries, including simple bill numbers and keyword searches, are offered, and produce a great wealth of information. The Library's staff appears to be working continuously to improve the content and appearance of the site, which fills me with as much pride (as a taxpayer) as it does chagrin (as a programmer trying to parse the pages).

We'll be using the Thomas site as the target for our examples. These worked at the time this article was written, but the Library may have improved their site out from under me by the time you read this. The examples, however, apply to any site, not just Thomas.

The Easy Part

Web browsing is a conversation between a browser on the user's machine, and a program that serves the Hypertext Transfer Protocol (HTTP) on the server machine. Most web browsing gets done through GET requests: At its simplest, the browser sends a message with the command "GET" and the URL for the desired web page. The server decodes the URL into the name of a specific file, and sends the contents of the file, wrapped in a suitable HTTP envelope, in the reply. The browser then does what it needs to with the file--usually displaying it on-screen.

The simplest kind of web-server computing comes from this insight: If the server has to do some computing anyway to decode the URL, why not encode requests to do more sophisticated computing tasks in the URL? Such URLs are still presented by GET requests, but include parameters for the desired computation after a question mark.

Apple has made it very easy to perform GET requests in Cocoa. The steps are: Form an NSURL for the request URL; ask for the result; wait for either the result or an error; handle the result or the error.

Basic Etiquette

But first, we pause for courtesy.

The user's computer won't necessarily be connected to the Internet when our code runs. It would be nice to know whether it's connected before we try to place the query, for two reasons. First, it's easier and cleaner to program that way. Second, if the user's computer has dial-up access to the Internet, making the query will cause the modem to dial out. Dialing the user's telephone without permission is rude; it would be a good idea to ask permission. Our first task is to check for connectivity, and ask permission if necessary.

Apple provides the necessary information through the SystemConfiguration framework. SystemConfiguration is not normally linked into a Cocoa project, so we add it to the project by selecting Add Frameworks... in Project Builder's Project menu, and selecting SystemConfiguration.framework in the /System/Library/Frameworks directory.

Listing 1 shows how to use the call SCNetworkCheckReachabilityByName in SystemConfiguration to preflight the net connection. All our main function needs to do is call ConnectivityApproved() to know whether to proceed with the query.

Listing 1a: Connectivity.h

Function declaration
#import <Cocoa/Cocoa.h>
BOOL      ConnectivityApproved(void);

Listing 1b: Connectivity.m

HowAmIReachingHost 
At the lowest level, ask the SystemConfiguration framework whether, and how, we can reach a named 
host. Render the result as an instance of HowConnected.

#import "Connectivity.h"
#import <SystemConfiguration/SCNetwork.h>
typedef enum {
   kCantReach,
   kWillConnect,
   kAmConnected
}   HowConnected;
HowConnected
HowAmIReachingHost(char *   hostName)
{
   SCNetworkConnectionFlags      theFlags;
   if (SCNetworkCheckReachabilityByName(hostName,
         &theFlags)) {
      if (theFlags & kSCNetworkFlagsReachable)
         return kAmConnected;
      if (theFlags & kSCNetworkFlagsConnectionAutomatic)
         return kWillConnect;
      else
         return kCantReach;
   }
   else
      return kCantReach;
   //   When in doubt, say it's unreachable.
}

ConnectivityApproved
For the particular case of thomas.loc.gov, see whether and how we can reach it. If we can't, inform 
the user and return NO. If we can without further action, return YES. If connecting requires dialing 
out, ask the user for permission, and return whether the user granted it.

BOOL
ConnectivityApproved(void)
{
   BOOL      retval = YES;   //   Assume connection is OK
   int      alertResult;
   switch (HowAmIReachingHost("thomas.loc.gov")) {
      case kCantReach:
         NSRunCriticalAlertPanel(
               @"Can't reach the Internet",
               @"Your computer could find no way to get a "
                  @"connection to the Library of Congress "
                  @"server (thomas.loc.gov).", 
               @"OK", nil, nil);
         //   Note that C compilers will join consecutive strings.
         //   GCC does this for @-strings as well as for C-strings.
         retval = NO;         //   Unreachable; return NO
         break;
      case kWillConnect:
         alertResult = NSRunAlertPanel(
               @"Will connect to the Internet",
               @"Your computer must connect to the Internet "
                  @"to answer your query. Is this all right?",
               @"Connect", @"Cancel", nil);
         if (alertResult == NSCancelButton)
            retval = NO;      //   User didn't want to dial out
            break;
      case kAmConnected:
         break;
   }
   
return retval;
}

Performing the GET

Even with preflighting, a GET transaction is embarrassingly easy. We start with the simple Cocoa application template in Project Builder. In Interface Builder, we can throw together a simple display of two text fields, a large text scroller, and a button, and instantiate a simple controller class in the application's .nib file, as shown in Figure 1. We don't have to change the Interface Builder-generated header file (Listing 2a) at all, and all that remains is to fill in the action method that Interface Builder generated for the Fetch button (Listing 2b).

Listing 2a: GETController.h

Class GETController
Notice that this is unchanged from the way Interface Builder generated it.
/* GETController */
#import <Cocoa/Cocoa.h>
@interface GETController : NSObject
{
    IBOutlet NSTextField *billField;
    IBOutlet NSTextField *congressField;
    IBOutlet NSTextView *resultText;
}
- (IBAction)doFetch:(id)sender;
@end


Figure 1. A simple GET window and its controller

Listing 2b: GETController.m

#import "GETController.h"
#import "Connectivity.h"
@implementation GETController
                                                            doFetch:
- (IBAction)doFetch:(id)sender
{
   //   Do nothing if we can't connect:
   if (! ConnectivityApproved())
      return;
   
   //   [1] Harvest the query parameters
   int               congress = [congressField intValue];
   int               bill = [billField intValue];
   
   //   [2] Format the query URL
   NSString *         urlString =
               [NSString stringWithFormat:
               @"http://thomas.loc.gov/cgi-bin/bdquery/z?"
               @"d%d:hr%05d:@@@L&summ2=m&",
               congress, bill];
   //   [3] Make an NSURL out of the string...
   NSURL *         theURL = [NSURL URLWithString: urlString];
   //   [4] ... and fetch the data as a single chunk of bytes
   NSData *         theHTML = [NSData dataWithContentsOfURL:
                                    theURL];
   //   [5] Turn the web page into styled text...
   NSAttributedString *
                     styledText = [[NSAttributedString alloc]
                                             initWithHTML: theHTML
                                             documentAttributes: nil];
   //   [6] ... and display it.
   [[resultText textStorage] 
         setAttributedString: styledText];
}
@end

The actual work of connecting to the Thomas server and retrieving the results occurs at [4] in Listing 2b, where an NSData is initialized with the class message dataWithContentsOfURL:. Many Cocoa classes--NSString, NSData, NSImage, and NSSound among them--can be initialized directly from URLs. I chose an NSData in this case, because I wanted to render the resulting HTML as styled text in an NSAttributedString at line [5], and the relevant initializer accepts an NSData object. If I had wanted to parse the results instead of just displaying them, I might use an NSString instead.

We can do better

That's all you need to do a GET query in a Cocoa application, but Cocoa makes it easy for us to do better. In the example we just saw, our program waits for the server's response to finish before proceeding with any other work: If the server takes more than a few seconds, the Quartz window server will detect that our program isn't handling user events, and will put up the dreaded "spinning beach-ball" cursor.

NSURL and NSURLHandle provide another way to perform GETs, offering more control and flexibility. A second Cocoa application, BetterGET, illustrates their use. BetterGet is just like CocoaGET, except that

  • Our controller class, BetterController, adds an outlet for the Fetch button.

  • BetterController adds a method, pendingTimer: to handle the progress bar animation.

  • BetterController implements the Objective-C protocol NSURLHandleClient.

You may be familiar with protocols under their Java name of "interfaces." A protocol defines a set of Objective-C messages. When a class claims to implement a protocol (by listing the protocol's name in <angle brackets> after its superclass in its @interface declaration), it makes a promise, enforced by the Objective-C compiler, that the class implements methods for every message in that protocol.

Our doFetch: method proceeds more or less as before, but instead of loading an NSData object directly from the target URL, we ask the NSURL for its underlying NSURLHandle. We register the BetterController as the NSURLHandle's client, and then tell it to loadInBackground.

Because NSURLHandleClient is a formal protocol (though some versions of the Cocoa documentation mistakenly claim it is "informal"), you must implement all five methods of the protocol. This is actually a blessing, because they provide a framework that takes you through the whole life cycle of your query.

  • URLHandleResourceDidBeginLoading is sent at the start of the download process. BetterController uses this opportunity to change the Fetch button to a Cancel button.

  • URLHandle:resourceDataDidBecomeAvailable: is ignored. BetterController doesn't use incoming data on-the-fly.

  • URLHandleResourceDidCancelLoading: reports the case in which the user canceled the downoad. BetterController cleans itself up in preparation for the next query.

  • URLHandle:resourceDidFailLoadingWithReason: informs BetterController that the query failed on the network side. Again, BetterController cleans up, but also puts up an alert informing the user of the problem.

  • URLHandleResourceDidFinishLoading:, last of all, is the "normal" end of the process. All of the data has come back from our query, and it's here we see the same few lines that finished the doFetch: method in the simple, one-step CocoaGET.

With practically no effort, Cocoa gave us a way to load and passively display web content in a simple application. With very little more, it gave us an application that downloads web content in the background, permits cancellation, and reports errors. Listing 3 tells the whole story.

Listing 3a: BetterController.h

//   BetterController.h
//   BetterGET
//   Copyright (c) 2002 Frederic F. Anderson
#import <Cocoa/Cocoa.h>
class BetterController
@interface BetterController : NSObject <NSURLHandleClient>
{
  IBOutlet NSTextField *      billField;
  IBOutlet NSTextField *      congressField;
   IBOutlet NSTextView *      resultText;
   IBOutlet NSButton *         fetchButton;
   NSURLHandle *                  myURLHandle;
}
- (IBAction) doFetch: (id) sender;
@end

Listing 3b: BetterController.m

//   BetterController.m
//   BetterGET
//   Copyright (c) 2002 Frederic F. Anderson
#import "BetterController.h"
#import "Connectivity.h"
@implementation BetterController
doFetch:
The default action method for the "Fetch" button in the application window. It harvests the bill and 
Congress numbers from the respective fields, forms the query URL, and initiates the query.

- (IBAction) doFetch: (id) sender
{
   if (! ConnectivityApproved())
      return;
   //   Harvest the numbers...
   int            congress = [congressField intValue];
   int            bill = [billField intValue];
   //   .. convert them to a URL...
   NSString *      urlString =
      [NSString stringWithFormat:
         @"http://thomas.loc.gov/cgi-bin/bdquery/z?"
            @"d%d:hr%05d:@@@L&summ2=m&",
         congress, bill];
   NSURL *         theURL = [NSURL URLWithString: urlString];
   //   ... and start a background fetch.
   myURLHandle = [theURL URLHandleUsingCache: NO];
   [myURLHandle addClient: self];
   [myURLHandle loadInBackground];
}

cancelFetch:
The alternate action method for the "Fetch" button, for use while the query is in progress. It simply 
tells the query to stop processing.

- (IBAction) cancelFetch: (id) sender
{
   [myURLHandle cancelLoadInBackground];
}

resetDownload
A common utility for the various URLHandleClient methods that signal the end of the query. It tears 
down the query and resets the UI for another query.

- (void) resetDownload
{
   //   Unsubscribe from the NSURLHandle
   if (myURLHandle) {
      [myURLHandle removeClient: self];
      myURLHandle = nil;
   }
   //   Change the Cancel button back to a Fetch button
   [fetchButton setTitle: @"Fetch"];
   [fetchButton setAction: @selector(doFetch:)];
}

URLHandleResourceDidBeginLoading
The URLHandleClient method signaling the start of a download. Starts the progress-bar timer and 
changes the Fetch button to be a Cancel button.

- (void) URLHandleResourceDidBeginLoading:
                                                                (NSURLHandle *)sender
{
   //   Change the fetch button to a Cancel button
   [fetchButton setTitle: @"Cancel"];
   [fetchButton setAction: @selector(cancelFetch:)];
}
URLHandle:resourceDataDidBecomeAvailable:
The URLHandleClient method signaling the arrival of data. Ignored.
- (void) URLHandle: (NSURLHandle *) sender
       resourceDataDidBecomeAvailable: (NSData *) newBytes
{
   //   Ignore. We're interested only in the completed data.
}

URLHandleResourceDidCancelLoading:
The URLHandleClient method signaling a user cancellation. Reset the UI for a new download.

- (void) URLHandleResourceDidCancelLoading: 
                                                                (NSURLHandle *)sender 
{
   [self resetDownload];
}

URLHandle:resourceDidFailLoadingWithReason:
The URLHandleClient method signaling a communications failure. Inform the user of the failure, using 
the message provided, and reset the UI for a new download.

- (void) URLHandle: (NSURLHandle *) sender
       resourceDidFailLoadingWithReason: (NSString *) reason
{
   [self resetDownload];
   NSRunAlertPanel(@"Fetch Failed", reason, 
                              @"OK", nil, nil);
}

URLHandleResourceDidFinishLoading:
The URLHandleClient method signaling a successful download. Display the results and reset the UI for 
a new download.

- (void) URLHandleResourceDidFinishLoading: 
                                                                (NSURLHandle *)sender
{
   //   Clean up Fetch button, etc.
   [self resetDownload];
   //   Collect the data and display it.
   NSData *            theHTML = [sender resourceData];
   NSAttributedString *   styledText =
      [[NSAttributedString alloc] initWithHTML: theHTML
                       documentAttributes: nil];
   [[resultText textStorage] 
            setAttributedString: styledText];
}
@end

Now it gets tricky

The GET request consists of an empty HTTP "envelope"--headers identifying the URL sought and other information like the referring web page, the browser being used, the browser's preferred language--and nothing more: The URL itself specifies the whole query.

The other way web browsers interact with server applications is through the POST query. Whereas queries in GET transactions are typically requests for simple lookups, POSTs are generally meant for transactions that are more complex, involving more data than can conveniently be put into a single URL. Alas, Cocoa doesn't include any direct way to make POST requests. Adding POST queries to Cocoa will be the subject of the rest of this series.

See you next month!


Fritz Anderson has been programming and writing about the Macintosh since 1984. He works (and seeks work) as a consultant in Chicago. You can reach him at fritza@manoverboard.org.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Freeway Pro 7.0.3 - Drag-and-drop Web de...
Freeway Pro lets you build websites with speed and precision... without writing a line of code! With its user-oriented drag-and-drop interface, Freeway Pro helps you piece together the website of... Read more
Cloud 3.3.0 - File sharing from your men...
Cloud is simple file sharing for the Mac. Drag a file from your Mac to the CloudApp icon in the menubar and we take care of the rest. A link to the file will automatically be copied to your clipboard... Read more
Cyberduck 4.6.5 - FTP and SFTP browser....
Cyberduck is a robust FTP/FTP-TLS/SFTP browser for the Mac whose lack of visual clutter and cleverly intuitive features make it easy to use. Support for external editors and system technologies such... Read more
Firefox 36.0 - Fast, safe Web browser. (...
Firefox for Mac offers a fast, safe Web browsing experience. Browse quickly, securely, and effortlessly. With its industry-leading features, Firefox is the choice of Web development professionals and... Read more
Thunderbird 31.5.0 - Email client from M...
As of July 2012, Thunderbird has transitioned to a new governance model, with new features being developed by the broader free software and open source community, and security fixes and improvements... Read more
VOX 2.4 - Music player that supports man...
VoxIt just sounds better! The beauty is in its simplicity, yet behind the minimal exterior lies a powerful music player with a ton of features & support for all audio formats you should ever need... Read more
A Better Finder Rename 9.46 - File, phot...
A Better Finder Rename is the most complete renaming solution available on the market today. That's why, since 1996, tens of thousands of hobbyists, professionals and businesses depend on A Better... Read more
WALTR 1.0.9 - Drag-and-drop any media fi...
WALTR is designed to make it easy to upload and convert any music or video file to an iPad or iPhone format for native playback. It supports a huge variety of media file types, including MP3, MP4,... Read more
Default Folder X 4.6.14 - Enhances Open...
Default Folder X attaches a toolbar to the right side of the Open and Save dialogs in any OS X-native application. The toolbar gives you fast access to various folders and commands. You just click on... Read more
Boom 2 1.1 - System-wide pro audio app f...
Boom 2 is a system-wide volume booster and equalizer app that is designed especially for OS X 10.10 Yosemite. It comes with a smart interface, self-calibrates itself according to your Mac, offers... Read more

Check Out the Trailer for the Upcoming F...
Check Out the Trailer for the Upcoming FINAL FANTASY: Record Keeper Posted by Jessica Fisher on February 26th, 2015 [ permalink ] DeNA and Square Enix have announced that | Read more »
Legacy Quest is an Upcoming Rouge-like T...
Legacy Quest is an Upcoming Rouge-like That’ll Kill the Whole Family Posted by Jessica Fisher on February 26th, 2015 [ permalink ] Nexon Co. | Read more »
Grudgeball: Enter the Chaosphere Review
Grudgeball: Enter the Chaosphere Review By Jordan Minor on February 26th, 2015 Our Rating: :: MUSCLE MENUniversal App - Designed for iPhone and iPad Regular Show gets an above average game.   | Read more »
Action RPG League of Angels – Fire Raide...
Gaia is being invaded by the Devil Prince and the demonic Devil Army at his disposal, and it’s up to you and your avatar to defeat him in League of Angels – Fire Raiders. Raise a mighty army from hundreds of recruitable angel heroes and take the... | Read more »
Burn Rubber on the Ice With a New Cars:...
Burn Rubber on the Ice With a New Cars: Fast as Lightning Update Posted by Jessica Fisher on February 26th, 2015 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
AdVenture Capitalist Review
AdVenture Capitalist Review By Jordan Minor on February 26th, 2015 Our Rating: :: DAS KAPITALUniversal App - Designed for iPhone and iPad An inadvertent Marxist manifesto.   | Read more »
Monster vs Sheep Review
Monster vs Sheep Review By Jennifer Allen on February 25th, 2015 Our Rating: :: SAMEY FUNUniversal App - Designed for iPhone and iPad What Monster vs Sheep lacks in variety it makes up for with stress relieving fun. At least, for a... | Read more »
Is Your Face Ready for the New Outwitter...
Is Your Face Ready for the New Outwitters 2.0 Trailer? Posted by Jessica Fisher on February 25th, 2015 [ permalink ] One Man Left Studios has announced that their turn-based strategy game, | Read more »
HowToFormat Review
HowToFormat Review By Jennifer Allen on February 25th, 2015 Our Rating: :: USEFUL TIPSiPhone App - Designed for the iPhone, compatible with the iPad Making a presentation and want to get it just right? HowToFormat teaches you how... | Read more »
Thermo Diem Review
Thermo Diem Review By Jennifer Allen on February 25th, 2015 Our Rating: :: GETS TO THE POINTUniversal App - Designed for iPhone and iPad Want to know whether it’s warmer or colder tomorrow? That’s precisely what Thermo Diem will... | Read more »

Price Scanner via MacPrices.net

New Travel Health App “My Travel Health” iOS...
Rochester, Minnesota based Travel Health and Wellness LLC has announced that its new iOS app help safeguard the user’s health when traveling abroad — “My Travel Health” is now available on the Apple... Read more
Sale! MacBook Airs for up to $115 off MSRP
B&H Photo has MacBook Airs on sale for up to $100 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 11″ 128GB MacBook Air: $799 100 off MSRP - 11″ 256GB MacBook Air: $999 $100... Read more
15-inch 2.0GHz Retina MacBook Pro (refurbishe...
The Apple Store has Apple Certified Refurbished previous-generation 15″ 2.0GHz Retina MacBook Pros available for $1489 including free shipping plus Apple’s standard one-year warranty. Their price is... Read more
Wither The iPad mini? End Of The Road Imminen...
AppleDailyReport’s Dennis Sellers predicts that the iPad mini is going to be left to wither on the vine, as it were, and then just allowed to fade away — a casualty of the IPhone 6 Plus and other... Read more
Android and iOS Duopoly Owns 96.3% of Smartph...
IDC reports that Android and iOS inched closer to total domination of the worldwide smartphone market in both the fourth quarter (4Q14) and the calendar year 2014 (CY14). According to data from the... Read more
13-inch 2.4GHz Retina MacBook Pro available f...
MacMall has the 2013 13″ 2.4GHz/128GB Retina MacBook Pro available for $999.99 for a limited time. Shipping is free. Their price is $300 off original MSRP, and it’s the only sub-$1000 new Retina... Read more
Save up to $300 on a new Mac, $30 on an iPad,...
Purchase a new Mac or iPad at The Apple Store for Education and take up to $300 off MSRP. All teachers, students, and staff of any educational institution qualify for the discount. Shipping is free,... Read more
Mac minis available for up to $75 off MSRP
MacMall has Mac minis on sale for up to $75 off MSRP including free shipping. Their prices are the lowest available for these models from any reseller: - 1.4GHz Mac mini: $459.99 $40 off - 2.6GHz Mac... Read more
WaterField Unveils Versatile Padded Gear Pouc...
San Francisco manufacturer WaterField Design’s new Padded Gear Pouch is a light and handy-sized, yet protective, organizer for every kind of take-along gear: technology, travel, toiletries,... Read more
College Student Deals: Additional $50 off Mac...
Take an additional $50 off all MacBooks and iMacs at Best Buy Online with their College Students Deals Savings, valid through April 11, 2015. Anyone with a valid .EDU email address can take advantage... Read more

Jobs Board

*Apple* Solutions Consultant - Retail Sales...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
*Apple* Solutions Consultant - Retail Sales...
**Job Summary** As an Apple Solutions Consultant (ASC) you are the link between our customers and our products. Your role is to drive the Apple business in a retail Read more
*Apple* Solutions Consultant (ASC)- Retail S...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
*Apple* Solutions Consultant - Retail Sales...
**Job Summary** As an Apple Solutions Consultant (ASC) you are the link between our customers and our products. Your role is to drive the Apple business in a retail Read more
Sr. Technical Services Consultant, *Apple*...
**Job Summary** Apple Professional Services (APS) has an opening for a senior technical position that contributes to Apple 's efforts for strategic and transactional Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.