TweetFollow Us on Twitter

Windoid XCMD
Volume Number:6
Issue Number:12
Column Tag:XCMD Corner

Related Info: Event Manager Window Manager

Windoids and HyperCard 2.0

By Donald Koscheka, MacTutor Contributing Editor

If you’ve been writing XCMDs for some time now, you might be a little concerned over how much work is involved in porting your xcmds to Hypercard 2.0. For the most part, this is a trivial process and you need not modify any of your code to support Hypercard 2.0. You will need to recompile with the new xcmd libraries though as the callback engine has been completely re-written to allow for a larger number of callbacks (some 75 as opposed to the 30 or so in HC1.0; the number is a little vague because I found a few callbacks in the library that are not documented anywhere).

For those of you using Think “C”, you will need to convert the XCMD library, “HyperXLib.o” to a Think “C” library. I got this file in MPW format and ran the “oConv” utility on it to convert it to something that Think can use. I then built a library from this. There is one small catch, the Library entry points are all uppercase. You will need to modify your calls to uppercase. For example, PasToZero becomes PASTOZERO. Of course, you might just wait until someone comes along with a more convenient library than the one that is currently distributed.

As I said, your xcmd should work “for the most part”. Certain xcmds will not work very well under Hypercard 2.0 or they will work but their behaviour will be such that you won’t recognize them (kind of like my 2 year old when she skips her nap).

The reason for this is that Hypercard 2.0 implements a completely new external window schema which offers a tremendous benefit to the xcmd writer but which also requires that you rethink your windowing strategy. The benefit of making your xcmds HC2.0 “windoid” friendly is tremendous -- windoids that function in the HC windoid layer will be able to communicate directly with Hypercard and use the Hypercard callbacks. In effect, you get a multiple-window Hypercard stack.

Windoids don’t come for free in Hypercard 2.0 and that’s good. In effect, Apple is leaving it up to each developer to decide what to do with external windows. The only rules that you must obey are those that will allow your windows to function within the external windows layer. This way, your windows will work correctly with other xcmds that also create external windows. Hypercard keeps track of which windows are owned by which xcmds, and it passes window events to each external windoid appropriately.

Windoids.c

Listing 1, “Windoids.c” is an external window xcmd skeleton. It incorporates two new functions of HC 2.0 xcmds: (1) it handles the “?” and “!” queries from the user and (2) it responds to windoid events. The former was covered last month is quite straightforward. We will look at the windoid events in greater detail in this and future columns.

Take a look at the entry point in Listing 1. Note that the first thing we do is check the number of parameters being passed to us by Hypercard. If the parameter count is less than zero (specifically, -1), then we are being passed an external windoid event for a window that we created earlier. If there is only one parameter and it’s “?” or “!” then return the appropriate information about the xcmd back to the caller. In the case of the “?”, you should return usage information. In the case of the “!” you should return a note about who created the xcmd and what it does. This is also a good place to put your copyright notice.

If the parameter count is greater than or equal to zero, then you treat the parameters as ordinary xcmd parameters. However, if the parameter count is less than zero, then you decode the parameter block in an entirely different manner. In this case, the first parameter, params[0] (“C”) or params[1] (Pascal), contains a POINTER to an xcmd event record. This record contains the following fields:

/* 1 */
 
struct XWEventInfo {
 EventRecordevent;
 WindowPtreventWindow;
 long   eventParams[9];
 Handle eventResult;
 }XWEventInfo, *XWEventInfoPtr;

The eventrecord is identical to the event manager event record. The windowPtr is a pointer to the windoid that should get this event. The event parameters and event result have other meanings that we will no doubt explore in the future but which are not required for the code in Listing 1.

In the listing, we call HandleHCEvent with the xcmd parameter block if paramcount is less than zero, otherwise we move to HandleHCmessage which should treat the parameter block like an ordinary xcmd activation. After a little thought this mechanism begs a question -- if we are responding to events in HandleHCEvent, why do we pass the entire parameter block rather than just the xwindow event record? This question gives rise to yet another question -- if that’s the case, why isn’t the parameter block just declared thusly:

/* 2 */

 typedef union{
 XCmdPBlock xcmdParams;
 XWEventInfoxwEventRecord;
 }

These questions did seem troubling to me at first -- I like to pass only those parameters that will be needed by a routine to that routine. An event handler should not need access to the parameter block, should it? The answer is absolutely and herein lies the answer -- by passing the entire parameter block to HandleHCevent, we are able to access Hypercard globals and make callbacks from inside our event loop. The answer to the second question should now be obvious -- we need to keep the parameter block intact so that xcmds can get to the callbacks. Thus the mechanism developed for handling events is correct. We can put our minds at ease and get back to the business of writing the code which is always easier once you develop this sort of intuitive feel for the data that you’re working with; a concept which is axiomatic in object oriented programming, by the way.

If your code needs to dispathc to HandleHCMessage, then you can treat the activation as a routine xcmd call and do whatever you like in HandleHCMessage. You might create a new external window here or close an existing window. Keep in mind that you should not directly call the toolbox calls to open and close windows. Rather, you must use the calls, NewXWindow and CloseXwindow which will create the windows for you and “register” them in the xwindow layer. Aside from that, window management is almost identical in Hypercard as in a stand-alone application.

/* 3 */

extern pascal WindowPtr NEWXWINDOW( XCmdPtr paramPtr,
 Rect *boundsRect,
 StringPtr title, 
        Boolean visible,
 short procID,
 Boolean color,
 Boolean floating); 

extern pascal WindowPtr GETNEWXWINDOW(XCmdPtr paramPtr,
 ResType  templateType,
 short  templateID,
 Boolean  color,
 Booleanfloating);  
extern pascal void CLOSEXWINDOW(XCmdPtr paramPtr, WindowPtr window);

When you create an external window, you use either the call to NewXWindow or the call to GetNewXWindow. Don’t draw in the window or do anything more yet. Hypercard will tell you when the window is ready for use by sending your event loop an Xwindow event called “xOpenEvt”. Not until your xcmd gets this event are you guaranteed to have a window that is ready for use.

At openEvt, you might want to invalidate the window to force an update or append some private data to the refcon. What you do is up to you, just don’t do anything to the window until you get the xOpenEvt.

Similarly, if you have a call to xwindoids of the form: Xwindoids “Close”, windowID then you should do nothing more than issue a call to CloseXWindow and go away. Later on, your xcmd will get the “xCloseEvt” event. At this time you can deallocate any private memory that the window uses and set the passFlag to true advising Hypercard that it’s okay to close the window.

Between xOpenEvt and xCloseEvt, your window will receive more or less normal events and should respond to them in a more or less normal fashion. Things start getting a little fuzzy here as I have noticed that this event loop can have different behaviors depending on what you do with the passflag. The code in Listing 1 does work, and you might want to play with the event loop to learn a little more about the behaviour of xwindows (or xwindoids as I prefer to call them to avoid confusion with that other windowing environment).

Pay particular attention to the goaway and drag code in listing 1. The goaway method does nothing more than advise Hypercard that the user wants to close the window. Later on, HC will pass back to use the xCloseEvt event. In the meantime, the window should just be in limbo.

The drag code works fine here. I discovered that setting the passflag to true will cause Hypercard to handle dragging the window. I hope to learn more about these undocumented parts of the window code as we go along. The content, activate and update methods are pure vanilla. On activate, we just check to see if we’re going active. I take the liberty of invalidating the window to force an update, but this should not be necessary. The invalRgn should be accumulated correctly for the window.

One last thing I would like to recommend is how you respond to suspend/resume events. I like the idea of hiding all my windows on suspend so that they aren’t in the way of the next application. On resume, you should show those windows that were visible at the last suspend. You will need to keep a separate flag for this, the window’s visible won’t be much use here.

In subsequent articles, we’ll hang more decorations on this skeleton and explore Hypercard xWindoids in greater detail. In the meanwhile, take a little time to master listing 1 and get comfortable with this “call and wait” mechanism for opening and closing windows. Overall I think the structure is quite workable and should lead to some very exciting extensions to Hypercard 2.0 in the future. If you discover anything about HC2.0 that you would like to share with your fellow developers, please drop me a line. My new AppleLink is D6845. See you next month.

Listing:  Windoids.c

/************************************/
/* File: Donald Koscheka.c*/
/* --------------------------------*/
/* ©1990 Donald Koscheka  */
/* All Rights Reserved    */
/************************************/
#include<HyperXCMD.h>
#include<HyperUtils.h>
#include<SetUpA4.h>

#ifndef MouseMovedEvt
#define MouseMovedEvt0xFA 
 /* Mouse moved event code*/
#endif
#ifndef SuspendResumeEvt
#define SuspendResumeEvt  0x01
 /* Suspend/Resume event code */
#endif
#define ResumeEvtMask0x1  
 /* Supend or Resume selector */
#define ConvertScrapMask  0x2 
 /* Scrap conversion flag */

pascal void HandleHCEvent( XCmdPtr pp);
pascal void HandleHCMessage( XCmdPtr pp);
pascal void UpdateWindow( WindowPtr wind );
pascal void DoContent(  WindowPtr wind, XWEventInfoPtr ip);

pascal void main( pp )
 XCmdPtrpp;
/************************************
* MAIN ENTRY POINT
************************************/
{
 pp->returnValue = NIL;
 
 if( pp->paramCount < 0 )
 HandleHCEvent( pp );
 else{
 if( pp->paramCount == 1 )
 if( **(pp->params[0]) == '!'  || **(pp->params[0]) == '?' ){
 switch(  **(pp->params[0]) ){
 case '!': 
 pp->returnValue = PASTOZERO( pp, "\pWindoids ©1990, 1991 Donald Koscheka, 
Inc.");
 return;
 case '?':
 pp->returnValue = PASTOZERO( pp, "\pWindoids [command] <parameters>" 
);
 return;
 }
 }
 HandleHCMessage( pp ); 
 }
 UnloadA4Seg( 0L );
 RestoreA4();
}

pascal void HandleHCEvent( pp )
 XCmdPtrpp;
/**********************************
* Handle events in our xWindows  
* returns true if the event was handled ok
**********************************/
{
 short  windoPart;
 Rect   r;
 XWEventInfoPtr  ip= pp->params[0];
 WindowPtrwhichWindow;
 
 pp->passFlag = FALSE;

 switch( ip->event.what ){
 case mouseDown:
 whichWindow = ip->eventWindow;
 windoPart = FindWindow( ip->event.where, &whichWindow );
 if( whichWindow )
 switch ( windoPart ){
 case inGoAway:
 if (TrackGoAway(whichWindow, ip->event.where)) {
 CLOSEXWINDOW( pp,whichWindow );
 pp->passFlag = FALSE;
 }
 break;
 case inDrag: /* handled by hypercard */
 pp->passFlag = TRUE;
 break;
 case inGrow:
 break;
 case inContent:
 if (whichWindow != FrontWindow() )
 SelectWindow( whichWindow );
 else{
 DoContent( whichWindow, ip );
 }
 pp->passFlag = TRUE;
 break;
 default: 
 break;
 }/* window part */
 break;
 case mouseUp:
 break;
 case keyDown:
 case autoKey:
 break;
 case activateEvt: /* [DK] ON ACTIVATE, DRAW THE MENUS,
 ON DEACTIVATE HIDE THE MENUS */
 if ( ip->event.modifiers & activeFlag ){
 r= (ip->eventWindow)->portRect;
 InvalRect( &r );
 }
 pp->passFlag = TRUE;
 break;
 case updateEvt: 
 UpdateWindow(  ip->eventWindow );
 pp->passFlag = TRUE;
 break;
 case app4Evt:
 {
 unsigned char *evtType = &(ip->event.message);
 
 switch( *evtType ){
 case MouseMovedEvt:
 break;
 case SuspendResumeEvt:
 if( ip->event.message & ResumeEvtMask )
 show_all_windows();
 else
 hide_all_windows();
 break;
 }
 }
 pp->passFlag = TRUE;
 break;
 case xOpenEvt:
 ShowWindow( ip->eventWindow );
 pp->passFlag = TRUE;
 break;
 case xCloseEvt:
 pp->passFlag = TRUE;
 break;
 default: 
 break; 
 } /* switch theEvent->what */
}

pascal void DoContent( wind, ip )
 WindowPtrwind;
 XWEventInfoPtr  ip;
/*************************************
* Handle the content region in a mouse down in an xwindow. ip is  a pointer 
to the HyperXevent record, needed to see where the mouse is and what 
the modifiers are.
*************************************/
{ SetPort( wind ); }

pascal void HandleHCMessage( pp )
 XCmdPtrpp;
/*****************************************
* Hypercard has sent us a message which we need to respond to. The command 
is passed in parameter 1 and the arguments are passed in parameter 2..N
* Perhaps you'll add a little parser here to accept valid commands and 
dispatch to the correct command handler. You may pass a command here 
called "openwindow" and another called "closewindow" to allow users to 
create & destroy external windows. 
*****************************************/
{ }

pascal void UpdateWindow( xwind )
 WindowPtrwind;
/******************
* Draw the contents of the window.
* You need to develop some mechanism for storing window specific data. 
 You might try storing the info in the window's refcon.  The choice is 
up to you.  
******************/
{
 BeginUpdate( wind );
 SetPort( wind );
 ClipRect( &wind->portRect );
 EndUpdate( wind );
}

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

VOX 2.8.6 - Music player that supports m...
VOX just sounds better! The beauty is in its simplicity, yet behind the minimal exterior lies a powerful music player with a ton of features and support for all audio formats you should ever need.... Read more
MacUpdate Desktop 6.1.3 - Search and ins...
MacUpdate Desktop 6 brings seamless 1-click app installs and version updates to your Mac. With a free MacUpdate account and MacUpdate Desktop 6, Mac users can now install almost any Mac app on... Read more
ExpanDrive 5.4.1 - Access cloud storage...
ExpanDrive builds cloud storage in every application, acts just like a USB drive plugged into your Mac. With ExpanDrive, you can securely access any remote file server directly from the Finder or... Read more
Espionage 3.6.6 - Simple, state-of-the-a...
Espionage offers state-of-the-art encryption and plausible deniability for your confidential data. Sometimes, encrypting your data isn't enough to protect it. That's why Espionage 3 goes beyond data... Read more
Pinegrow Web Designer 2.94 - Mockup and...
Pinegrow Web Designer is desktop app that lets you mockup and design webpages faster with multi-page editing, CSS and LESS styling, and smart components for Bootstrap, Foundation, Angular JS, and... Read more
1Password 6.3.3 - Powerful password mana...
1Password is a password manager that uniquely brings you both security and convenience. It is the only program that provides anti-phishing protection and goes beyond password management by adding Web... Read more
Sublime Text 3126 - Sophisticated text e...
Sublime Text is a sophisticated text editor for code, markup, and prose. You'll love the slick user interface, extraordinary features, and amazing performance. Features Goto Anything. Use Goto... Read more
ForkLift 3.0 Beta 2 - Powerful file mana...
ForkLift is a powerful file manager and ferociously fast FTP client clothed in a clean and versatile UI that offers the combination of absolute simplicity and raw power expected from a well-executed... Read more
OmniFocus 2.7.1 - GTD task manager with...
OmniFocus helps you manage your tasks the way that you want, freeing you to focus your attention on the things that matter to you most. Capturing tasks and ideas is always a keyboard shortcut away in... Read more
CleanApp 5.1.1 - Application deinstaller...
CleanApp is an application deinstaller and archiver.... Your hard drive gets fuller day by day, but do you know why? CleanApp 5 provides you with insights how to reclaim disk space. There are... Read more

Leaf for Twitter (Social Networking)
Leaf for Twitter 1.0.1 Device: iOS iPhone Category: Social Networking Price: $4.99, Version: 1.0.1 (iTunes) Description: | Read more »
Banner Saga 2 (Games)
Banner Saga 2 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: The epic award winning story-based role-playing game continues its emotional journey across a breaking world. Lead your Viking... | Read more »
Concrete Jungle (Games)
Concrete Jungle 1.16 Device: iOS Universal Category: Games Price: $4.99, Version: 1.16 (iTunes) Description: A follow up to the puzzle hit 'MegaCity'! Concrete Jungle is a new take on the city building genre that swaps micro-... | Read more »
5 great apps for the budget traveller
Travelling abroad, or even within your home country, has never been easier thanks to our handy smartphone companions. There are hundreds of apps on the market that promise to make your world journeys hassle-free, but we've selected five of the... | Read more »
Zip—Zap (Games)
Zip—Zap 1.01 Device: iOS Universal Category: Games Price: $1.99, Version: 1.01 (iTunes) Description: Touch to contract.Release to let go.Bring the clumsy mechanical beings home. · · · over 100 levelsno adsno in-app-purchases Zip—... | Read more »
Paperback: The Game (Games)
Paperback: The Game 1.0 Device: iOS Universal Category: Games Price: $3.99, Version: 1.0 (iTunes) Description: You are an author trying to finish kitschy paperback novels. Complete Westerns, Science Fiction, Romance or even a Crime... | Read more »
How to Rule With a Firm Hand in My Majes...
My Majesty is a kingdom management sim not unlike August’s magisterial hit, Reigns. It’s essentially a reskin of developer Tigrido’s previous management sim, Dictator. As supreme ruler of the land, you must consult with a number of subjects to... | Read more »
Our 5 Favorite iMessage Sticker Packs
At long last, iMessage joins the ranks of messaging apps the likes of LINE and Whatsapp, adding an impressive collection of stickers. They’re a great way to add a little something extra to your daily conversations. [Read more] | Read more »
How to get past Vulture Island's tr...
Vulture Island is a colorful and quirky mish-mash of platforming and puzzles. It’s creative and fresh, but sometimes the game can throw a curveball at you, leaving you stuck as to how you should progress. These tips will help you explore smoothly... | Read more »
The new Clash of Kings is just for Weste...
If you’ve played the original Clash of Kings, you’ll probably recognise the city building, alliance forging and strategic battles in Clash of Kings: The West. What sets this version apart is that it’s tailor made for a Western audience and the... | Read more »

Price Scanner via MacPrices.net

Apple refurbished Mac minis available startin...
Apple has Certified Refurbished Mac minis available starting at $419. Apple’s one-year warranty is included with each mini, and shipping is free: - 1.4GHz Mac mini: $419 $80 off MSRP - 2.6GHz Mac... Read more
13-inch 2.5GHz MacBook Pro available for $928...
Overstock has the 13″ 2.5GHz MacBook Pro available for $927.99 including free shipping. Their price is $171 off MSRP. Read more
Buying McLaren Would Give Apple Instant Car C...
Apple “iCar” rumors have waxed and waned over the years, piquing interest and speculation as to whether Apple is seriously interested in getting into the automotobile business, either in a joint... Read more
Aetna to Transform Members’ Consumer Health E...
Health care benefits company Aetna, which has an estimated 46.3 million clients, today announced a new initiative to revolutionize members consumer health experience by combining the power of iOS... Read more
USB-IF Announces USB Audio Device Class 3.0 S...
USB Implementers Forum (USB-IF), the support organization for the advancement and adoption of USB technology, today announced the USB Audio Device Class 3.0 specification to establish USB Audio over... Read more
Clearance 12-inch 1.2GHz Retina MacBooks, App...
Apple has Certified Refurbished 2015 12″ 1.2GHz Retina MacBooks available for $1189, or $410 off original MSRP. Apple will include a standard one-year warranty with each MacBook, and shipping is free... Read more
Logitech SmartDock and Skype For Business Com...
Logitech has announced Logitech SmartDock, an AV meeting room solution designed in collaboration with Microsoft. Logitech SmartDock works with Skype for Business and qualified devices, including... Read more
27-inch iMacs on sale for up to $220 off MSRP
B&H Photo has 27″ Apple iMacs on sale for up to $200 off MSRP including free shipping plus NY sales tax only: - 27″ 3.3GHz iMac 5K: $2099 $200 off MSRP - 27″ 3.2GHz/1TB Fusion iMac 5K: $1899.99 $... Read more
Apple Macs and iPads available for up to $300...
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, and... Read more
Save up to $600 with Apple refurbished Mac Pr...
Apple has Certified Refurbished Mac Pros available for up to $600 off the cost of new models. An Apple one-year warranty is included with each Mac Pro, and shipping is free. The following... Read more

Jobs Board

*Apple* Retail - Multiple Positions- Chicago...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Retail - Multiple Positions- Raleigh...
Job Description:SalesSpecialist - Retail Customer Service and SalesTransform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
User Support Specialist *Apple* Product Spe...
…Description:Ciber, Inc. is seeking a User Support Specialist - Apple Product Support in Nashville, TN!Responsibilities:Support, implementation, and upgrade of Read more
Restaurant Manager (Neighborhood Captain) - A...
…in every aspect of daily operation. WHY YOU'LL LIKE IT: You'll be the Big Apple . You'll solve problems. You'll get to show your ability to handle the stress and Read more
US- *Apple* Store Leader Program - Apple (Un...
…Summary Learn and grow as you explore the art of leadership at the Apple Store. You'll master our retail business inside and out through training, hands-on Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.