TweetFollow Us on Twitter

January 92 - Postcard from Windows Land - Is Windows object-oriented?

Postcard from Windows Land - Is Windows object-oriented?

James Plamondon

When the Microsoft gang started writing Windows back in the mid-eighties, they were all excited about object programming. They, like Apple, toured Xerox PARC and saw what Xerox was doing with bit-mapped displays, windows, mice, and so on. Microsoft, like Apple, thought this stuff was going to be the wave of the future-so they went home and started working on a cool object-oriented operating system.

Then reality hit. Their target platform, the standard IBM PC of their day, was totally unable to handle the strain of a truly object-oriented system. So, like Apple, Microsoft compromised, and wrote a procedural operating system with an object-oriented flavor.

For whatever reason, however, Windows was unsuccessful throughout its development-until around the time Microsoft's OS/2 deal with IBM fell through-whereas the Mac OS was the star at Apple from soon after its inception. So the Windows operating system is only now beginning to flower, as the Mac OS did about four years ago.

What's amazing to me is how fast Windows is moving. Whereas Apple took ages to bring out System 7, Microsoft is bringing out Windows 3.1 just 18 months (roughly) after 3.0 hit the shelves. And Windows 3.1 should really be called Windows 4; it is a really big improvement over Windows 3.0 (which has sold over five million copies in the last year, so it's no slouch, either).

But is Windows object-oriented? Absolutely not-if, by "object-oriented," you mean written in an object programming language. Given Windows' origins and history, it couldn't be. Smalltalk and Simula were the only decent object programming languages available at the product's inception, and neither would give adequate performance on their target system. So Microsoft did the best it could under the restraints it was under at the time. And in at least one way, Microsoft did a better job than Apple.

Windows, true to its name, has a real windowing system; the Mac does not. This should come as no surprise to MacApp programmers; one of the most important benefits MacApp provides to Mac programmers is-you guessed it-a windowing system, in the form of MacApp views. [A Windows "window" is equivalent to a MacApp "view;" a MacApp "window" is equivalent to a Windows "frame window."] It is considerably easier to write an application framework for Windows than for the Mac, because a Windows framework could use the native windowing system. Zillions of lines of code could be saved.

On the Mac, when you create a window, you get a pointer to a data structure. This data structure is completely dumb. There's no way to call its methods or send it messages. In Windows, on the other hand, one can define a window class, and associate with this class a number of attributes and-importantly-a window procedure (WinProc). When you create a window, you must specify the class of the window. The window reference you get back is a unique window identifier, but it's completely "blind." You can't use it as a pointer to get at its data directly. Instead, you have to "send the window a message" to act on it.

"Sending the window a message" works just like "sending a message" to a Mac CDEF, WDEF, or other code resource. You call a procedure with an integer argument that indicates which message you're sending, and a couple of other arguments that can hold additional data. (Before you snort in disdain at the notion of using integral message discriminators, think about MacApp's use of command numbers in TEvtHandler.DoMenuCommand().)

So, Windows does a better job of data abstraction and encapsulation, at least with regard to window data structures. But is this abstraction and encapsulation enough to make it object-oriented?

Well, maybe not-but there's more. Having defined a window class, one can "subclass" the window class. Now, before you get all excited, let me admit that it's not "real" subclassing, using the definition used by object programming languages. But it's not a bad simulation.

Let's say you want to write a variation of the standard Windows "edit" control-to validate its entries as dates, perhaps. You would need to get a copy of the "edit" class' class info (by calling GetClassInfo()), and modify the resulting copy to use your new class name ("edit_date"). Also, you would save off the class info's pointer to the "edit" class' WinProc, and store the "edit_date" class' WinProc pointer in its place (in the copy). Then, you would call RegisterClass() to tell Windows that the window class existed.

Having done this, you can then create a window of class "edit_date" by telling Windows to do so. It will respond by handing you back a unique window identifier. From then on, both Windows and your application will interact with the window by sending it messages. Messages are sent to the window by calling the Windows function SendMessage() with the window ID as the first argument, or by calling other Windows functions that eventually call SendMessage().

SendMessage()'s prototype is roughly as follows:

long SendMessage(HWND hWnd, short wMsg, short wParam, long lParam);

[This prototype has been simplified for ease of understanding by the MacApp audience. The correct prototype is "LONG FAR PASCAL MyWinProc(HWND hWnd, WORD wMsg, WORD wParam, LONG lParam)."]

"hWnd" is the unique window ID. When SendMessage() is called on a given window, the window's WinProc is called. The WinProc's prototype is almost the same as that of SendMessage(); calling SendMessage() can be viewed as a polymorphic call to a window's message procedure.

The WinProc typically contains a huge switch statement (in Pascal, case statement) that forwards the message to the appropriate message handler (much like TApplication.DispatchEvent()). And, since you carefully saved off the standard Windows "edit" window class' WinProc pointer before calling RegisterClass(), you can call it from within your "edit_date" window class' WinProc-much like calling the inherited implementation of a method in an OOP language. It ain't pretty, but it works.

So, maybe Windows is object-oriented, and maybe it's not. Maybe, as a friend of mine said recently, object-orientation is not a binary, yes-or-no quality, but rather a continuum. If so, then Windows is certainly "more object-oriented" than the Mac OS, while being "less object-oriented" than MacApp.

The answer to the question may be irrelevant. It is relevant, though, that your MacApp experience will put you way ahead of the game in Windows programming. MacApp software development tools are on the cutting edge, while those for Windows are still blunt instruments, suitable only for beating code into submission.

But the bottom line remains the same: Windows is selling at an incredible rate, and will be a significant force in the microcomputer industry for years to come. By learning to program in Windows, you will be assuring your financial security for at least the next decade.

As the old saying goes, in the land of the blind, the one-eyed man is King; and with Windows selling at an incredible rate, the Land of the Blind is expanding rapidly. We MacAppers know how to wring the most out of an even vaguely-object-oriented system; you can see the opportunity this presents to us, even with one eye shut.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Fantastical 2.3.6 - Create calendar even...
Fantastical 2 is the Mac calendar you'll actually enjoy using. Creating an event with Fantastical is quick, easy, and fun: Open Fantastical with a single click or keystroke Type in your event... Read more
Creative Kit 1.1 - $149.99
Creative Kit 2016--made exclusively for Mac users--is your ticket to the most amazing images you've ever created. With a variety of powerful tools at your fingertips, you'll not only repair and fine-... Read more
iMazing 2.2.3 - Complete iOS device mana...
iMazing (was DiskAid) is the ultimate iOS device manager with capabilities far beyond what iTunes offers. With iMazing and your iOS device (iPhone, iPad, or iPod), you can: Copy music to and from... Read more
Apple Configurator 2.4 - Configure and d...
Apple Configurator makes it easy to deploy iPad, iPhone, iPod touch, and Apple TV devices in your school or business. Use Apple Configurator to quickly configure large numbers of devices connected to... Read more
WhatRoute 2.0.18 - Geographically trace...
WhatRoute is designed to find the names of all the routers an IP packet passes through on its way from your Mac to a destination host. It also measures the round-trip time from your Mac to the router... Read more
Posterino 3.3.5 - Create posters, collag...
Posterino offers enhanced customization and flexibility including a variety of new, stylish templates featuring grids of identical or odd-sized image boxes. You can customize the size and shape of... Read more
Skim 1.4.28 - PDF reader and note-taker...
Skim is a PDF reader and note-taker for OS X. It is designed to help you read and annotate scientific papers in PDF, but is also great for viewing any PDF file. Skim includes many features and has a... Read more
Apple macOS Sierra 10.12.4 - The latest...
With Apple macOS Sierra, Siri makes its debut on Mac, with new features designed just for the desktop. Your Mac works with iCloud and your Apple devices in smart new ways, and intelligent... Read more
Apple Numbers 4.1 - Apple's spreads...
With Apple Numbers, sophisticated spreadsheets are just the start. The whole sheet is your canvas. Just add dramatic interactive charts, tables, and images that paint a revealing picture of your data... Read more
Xcode 8.3 - Integrated development envir...
Xcode includes everything developers need to create great applications for Mac, iPhone, iPad, and Apple Watch. Xcode provides developers a unified workflow for user interface design, coding, testing... Read more

Hearthstone celebrates the upcoming Jour...
Hearthstone gets a new expansion, Journey to Un'Goro, in a little over a week, and they'll be welcoming the Year of the Mammoth, the next season, at the same time. There's a lot to be excited about, so Blizzard is celebrating in kind. Players will... | Read more »
4 smart and stylish puzzle games like Ty...
TypeShift launched a little over a week ago, offering some puzzling new challenges for word nerds equipped with an iOS device. Created by Zach Gage, the mind behind Spelltower, TypeShift boasts, like its predecessor, a sleak design and some very... | Read more »
The best deals on the App Store this wee...
Deals, deals, deals. We're all about a good bargain here on 148Apps, and luckily this was another fine week in App Store discounts. There's a big board game sale happening right now, and a few fine indies are still discounted through the weekend.... | Read more »
The best new games we played this week
It's been quite the week, but now that all of that business is out of the way, it's time to hunker down with some of the excellent games that were released over the past few days. There's a fair few to help you relax in your down time or if you're... | Read more »
Orphan Black: The Game (Games)
Orphan Black: The Game 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: Dive into a dark and twisted puzzle-adventure that retells the pivotal events of Orphan Black. | Read more »
The Elder Scrolls: Legends is now availa...
| Read more »
Ticket to Earth beginner's guide: H...
Robot Circus launched Ticket to Earth as part of the App Store's indie games event last week. If you're not quite digging the space operatics Mass Effect: Andromeda is serving up, you'll be pleased to know that there's a surprising alternative on... | Read more »
Leap to victory in Nexx Studios new plat...
You’re always a hop, skip, and a jump away from a fiery death in Temple Jump, a new platformer-cum-endless runner from Nexx Studio. It’s out now on both iOS and Android if you’re an adventurer seeking treasure in a crumbling, pixel-laden temple. | Read more »
Failbetter Games details changes coming...
Sunless Sea, Failbetter Games' dark and gloomy sea explorer, sets sail for the iPad tomorrow. Ahead of the game's launch, Failbetter took to Twitter to discuss what will be different in the mobile version of the game. Many of the changes make... | Read more »
Splish, splash! The Pokémon GO Water Fes...
Niantic is back with a new festival for dedicated Pokémon GO collectors. The Water Festival officially kicks off today at 1 P.M. PDT and runs through March 29. Magikarp, Squirtle, Totodile, and their assorted evolved forms will be appearing at... | Read more »

Price Scanner via MacPrices.net

Is A New 10.5-inch iPad Still Coming In April...
There was no sign or mention of a long-rumored and much anticipated 10.5-inch iPad Pro in Apple’s product announcements last week. The exciting iPad news was release of an upgraded iPad Air with a... Read more
T-Mobile’s Premium Device Protection Now Incl...
Good news for T-Mobile customers who love their iPhones and iPads. The “Un-carrier” has become the first national wireless company to give customers AppleCare Services at zero additional cost as part... Read more
FileWave Ensures Support for Latest Apple OS...
FileWave multi-platform device management providers announced support for Apple’s release yesterday of iOS 10.3, macOS Sierra 10.12.4, and tvOS 11.2. FileWave has a history of providing zero-day... Read more
Use Apple’s Education discount to save up to...
Purchase a new Mac or iPad using Apple’s Education Store 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
Apple refurbished Apple Watches available sta...
Apple is now offering Certified Refurbished Series 1 and Series 2 Apple Watches for 14-16% off MSRP, starting at $229. An Apple one-year warranty is included with each watch. Shipping is free: Series... Read more
9-inch 32GB Space Gray iPad Pro on sale for $...
B&H Photo has the 9.7″ 32GB Space Gray Apple iPad Pro on sale for $549 for a limited time. Shipping is free, and B&H charges NY sales tax only. Their price is $50 off MSRP. Read more
13-inch MacBook Airs on sale for $100-$150 of...
B&H Photo has 13″ MacBook Airs on sale for up to $150 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 13″ 1.6GHz/128GB MacBook Air (MMGF2LL/A): $899 $100 off MSRP - 13″ 1.... Read more
13-inch MacBook Airs, Apple refurbished, in s...
Apple has Certified Refurbished 2016 13″ MacBook Airs available starting at $849. An Apple one-year warranty is included with each MacBook, and shipping is free: - 13″ 1.6GHz/8GB/128GB MacBook Air: $... Read more
12-inch Retina MacBooks on sale for $1199, sa...
B&H has 12″ 1.1GHz Retina MacBooks on sale for $100 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 12″ 1.1GHz Space Gray Retina MacBook: $1199 $100 off MSRP - 12″ 1.1GHz... Read more
Save up to $260 with Apple refurbished 12-inc...
Apple has Certified Refurbished 2016 12″ Retina MacBooks available for $200-$260 off MSRP. Apple will include a standard one-year warranty with each MacBook, and shipping is free. The following... Read more

Jobs Board

Fulltime aan de slag als shopmanager in een h...
Ben jij helemaal gek van Apple -producten en vind je het helemaal super om fulltime shopmanager te zijn in een jonge en hippe elektronicazaak? Wil jij werken in Read more
Desktop Analyst - *Apple* Products - Montef...
…technology to improve patient care. JOB RESPONSIBILITIES: Provide day-to-day support for Apple Hardware and Software in the environment based on the team's support Read more
*Apple* Mobile Master - Best Buy (United Sta...
**493168BR** **Job Title:** Apple Mobile Master **Location Number:** 000827-Denton-Store **Job Description:** **What does a Best Buy Apple Mobile Master do?** At Read more
Fulltime aan de slag als shopmanager in een h...
Ben jij helemaal gek van Apple -producten en vind je het helemaal super om fulltime shopmanager te zijn in een jonge en hippe elektronicazaak? Wil jij werken in Read more
*Apple* Mobile Master - Best Buy (United Sta...
**492889BR** **Job Title:** Apple Mobile Master **Location Number:** 000886-Norwalk-Store **Job Description:** **What does a Best Buy Apple Mobile Master do?** Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.