TweetFollow Us on Twitter

Jan 95 Top 10
Volume Number:11
Issue Number:1
Column Tag:Think Top 10

Think Top 10

This monthly column, written by Symantec’s Technical Support Engineers, aims to provide you with information on Symantec products. Each month we cover either a specific application of tools or a “Q&A” list.

By Craig Conner and Rick Hartmann, Symantec Technical Support

Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.

Q: Why do I get a bus error when I try to use the VIA timer option for the profiler?

A: The Symantec C++ 7 documentation states that the profiler uses the VIA (Versatile Interface Adapter) timer which ticks every 1.28 microseconds. If you want to use Ticks (1/60 of a second), modify the profiler code to do so. Not all Macintosh models contain a VIA timer chip. To find out if your Mac has a VIA timer chip, you should use the functions gestaltHasVIA1 or gestaltHasVIA2 (Mac II).

If you have the chip, modify profile.c as follows:

#ifdef _VIATIMER_ 
  #define Ticks VIA_Ticks() 
#else 
  #ifdef __CONDITIONALMACROS__ 
  #define Ticks LMGetTicks() 
  #endif 
#endif

Next, remove all of the #ifdef __CONDITIONALMACRO__ statements in profile.c, then use the Ticks assignments.

Q: Why can’t I use fopen to open more than 12 files?

A: stdio.h defines a table for keeping track of open files. This table is defined as:

extern FILE __file[FOPEN_MAX]; 

where FOPEN_MAX is declared as 15. Three streams are reserved for stdin, stdout, and stderr which leaves 12 more for you to use. To open more than twelve files, increase the value of FOPEN_MAX and recompile the ANSI library. Alternatively, you can use Macintosh Toolbox calls to open files; those files are not counted against the limit.

Q: When I try to use TESetWordBreak I get a link error.

A: Below is an example of how to use TESetWordBreak with the current Universal Headers. The changes only apply to 68K use. You can use TESetWordBreak directly when compiling for PowerPC. Basically the problem is that Apple doesn’t provide the glue for the new routine name, but has written the Universal Headers as if they did. [This was fixed on ETO #15. Interface.o on ETO #15 has an extra entry point added for TESetWordBreak. There was also the same problem and fix for SetClikLoop -> TESetClickLoop - Ed stb]

#include <TextEdit.h>

// Need to undo the redefinition of SetWordBreak in the Universal Headers when in 
// 68K.  Glue for SetWordBreak is in MacTraps, but there is no glue for 
// TESetWordBreak.  We also need to redefine any calls using the new name 
// for the same reason

#ifndef powerc 
#undef SetWordBreak 
extern pascal void SetWordBreak(WordBreakUPP wBrkProc,TEHandle hTE); 

#define TESetWordBreak(wBrkProc, hTE) SetWordBreak(wBrkProc, hTE) 
#endif

pascal Boolean myWordBreaker(Ptr textPtr, short offset );

void foo() 
{
 TEHandle hTE;
 WordBreakUPP brk = NewWordBreakProc(myWordBreaker);
 
 // either of the following two are ok
 SetWordBreak(brk, hTE);
 TESetWordBreak(brk, hTE); 
}

pascal Boolean myWordBreaker(Ptr textPtr, short offset ) 
{
 if (textPtr[offset] == 's' )  
  return true;
 else
  return false; 
}

Q: How do I use new to obtain a two dimensional array?

A: Each row element in a two dimensional array is actually a pointer to the row. To access a two dimensional array using new, you need to tell the compiler that you want two dimensions like so:

int (*intarr)[3] = new int[2][3];

Then you can access the memory using array references, e.g. intarr[1][1].

Q: Do I have to declare objects as “volatile” in TRY/CATCH macros?

A: Yes. When a TRY is executed, all registers are saved. When CATCH is executed, the registers are restored to the saved state. If you change a value of a non-volatile variable within a TRY block, it’s possible that the value will be restored to what it was before the TRY when the CATCH is triggered. If you use a volatile variable, the compiler forces its value to be saved to memory any time it’s changed, and won’t let it be cached in a register.

Q: Do I need to recompile the ANSI++ library with 8-byte doubles to use it in a Visual Architect project?

A: 8-byte doubles are no longer required for VA (or other TCL) projects. The default VA project still ships with 8-byte doubles on while the ANSI++ library ships with it off. It is ok to turn this option off in your TCL projects.

Q: How do I trap CRadioControl commands within a dialog?

A: By default the values of radio buttons are not verified until a dialog box finishes the DoModalDialog() function. DoModalDialog returns a command of type long. At this point, the programmer should create a switch statement where the values of radio buttons are checked with the (CRadioGroupPane*)FindViewByID->GetStationID(theRadioDITL) method.

The problem with this style is that the values of the radio buttons are obtained after the dialog is dismissed. Often, the programmer will want to have the changing values of radio buttons change the characteristics of items in the dialog itself. For example, a programmer may want the font of a CDialogText to change according to the settings of radio buttons.

The solution has three parts.


1) Set up your derived CDLOGDirector class so that it owns the CRadioControl pointers. This will give you access to the radio buttons throughout your class.


2) When you instantiate CRadioControl make a call to SetClickCmd(). Make sure to set each button with its own command. For the command to work, it must be something other than zero.

 myRadio1->SetClickCmd( cmdFontGeneva);

3) Add a DoCommand() function to your derived CDLOGDirector class.

 MyDialogDirector::DoCommand(theCommand) {
 
 switch (theCommand)
  {
  case cmdFontGeneva:
  myDialogText->SetTextFont(3);    //Set font to geneva
  break;
  case cmdFontChicago:
  myDialogText->SetTextFont(0);    //Set font to chicago
  break;
  default:
  inherited::DoCommand(theCommand);  //important
  }
 }

The default statement is extremely important for this construct. The inherited DoCommand() is trapped by CDialogDirector to process the OK and Cancel command. If you do not trap these commands yourself, or do not have an inherited method trap them, you will not be able to dismiss the dialog.

Q: In Visual Architect, can I have main windows that are not based on CSaver?

A: In Visual Architect 7.0.4, the code generation does not recognize the checkbox for the “Use File” option. The solution is to change the code in the “GenerateTCLApp” VA template file for documents, as follows:

$elseif class.basename == "CDocument"$
 $generate "Source:$class.name$.cp" "Doc_cp" once$
 $generate "Source:$class.name$.h" "Doc_h" once$
 $if class.view.usefile$
  $generate "Source:ItsContents_$class.name$.h"  "ItsContentsClass_h" 
once$
  $generate "Source:CSaver_$class.name$.cpp" "CSaver_class_cpp"  once$
 $end if$
 $define do_document 1$

Q: How do I change the font attributes in CStdPopupPane?

A: Changing the font of popup menus is not intuitively obvious. The process involves several steps.


1) Create a menu resource with a title and a menu item. Remember its ID number.


2) Instantiate your CStdPopupPane.

myPopUp = TCL_NEW( CStdPopupPane, (menuID, itsWindow, this,
  0,0, 100,100, TRUE, FALSE, FALSE));

3) Make sure to #include CTextEnvirons. Then create a local pointer to a TextInfoRec, and fill the struct with the text information that you want in your popup.

TextInfoRec * myTextInfo = new TextInfoRec;

myTextInfo->fontNumber = 10;
myTextInfo->theSize = 12;
myTextInfo->theStyle = bold;
myTextInfo->theMode = qd.thePort->txMode;

4) Cast the itsEnvironment member of the CStdPopUpPane as a CTextEnvirons, allocate memory for it, and call the SetTextInfo() method.

(CTextEnvirons*)myPopUp->itsEnvironment = 
 TCL_NEW (CTextEnvirons, (FALSE));
((CTextEnvirons*)myPopUp->itsEnvironment)-> 
 SetTextInfo(myTextInfo);

5) Don’t forget to delete the temporary variable myTextInfo.

Q: Visual Architect projects take so long to compile. How can I reduce the compile time? (Reprise)

A: In October’s Think Top 10 we had a question concerning saving time when using VA projects. The answer we gave was to compile the @1.Π file in the Visual Architect Project Model. The problem with that is that the debugging information doesn’t get copied when you create a new project.

To avoid that problem, before you compile, uncheck the Store Debug Info Separately switch in the debugger options for the Think Project Manager. This will store the debug info inside of the project file, so that it will be copied into your new project. If you wish, you can uncheck the switch after creating your project; it won’t force a recompilation.

Thanks to Michael Hopkins, Mark Baldwin, Steve Howard,
Phil Shapiro, Rich Parker, and the rest of the gang.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Latest Forum Discussions

See All

Combo Quest (Games)
Combo Quest 1.0 Device: iOS Universal Category: Games Price: $.99, Version: 1.0 (iTunes) Description: Combo Quest is an epic, time tap role-playing adventure. In this unique masterpiece, you are a knight on a heroic quest to retrieve... | Read more »
Hero Emblems (Games)
Hero Emblems 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: ** 25% OFF for a limited time to celebrate the release ** ** Note for iPhone 6 user: If it doesn't run fullscreen on your device... | Read more »
Puzzle Blitz (Games)
Puzzle Blitz 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: Puzzle Blitz is a frantic puzzle solving race against the clock! Solve as many puzzles as you can, before time runs out! You have... | Read more »
Sky Patrol (Games)
Sky Patrol 1.0.1 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0.1 (iTunes) Description: 'Strategic Twist On The Classic Shooter Genre' - Indie Game Mag... | Read more »
The Princess Bride - The Official Game...
The Princess Bride - The Official Game 1.1 Device: iOS Universal Category: Games Price: $3.99, Version: 1.1 (iTunes) Description: An epic game based on the beloved classic movie? Inconceivable! Play the world of The Princess Bride... | Read more »
Frozen Synapse (Games)
Frozen Synapse 1.0 Device: iOS iPhone Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: Frozen Synapse is a multi-award-winning tactical game. (Full cross-play with desktop and tablet versions) 9/10 Edge 9/10 Eurogamer... | Read more »
Space Marshals (Games)
Space Marshals 1.0.1 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.1 (iTunes) Description: ### IMPORTANT ### Please note that iPhone 4 is not supported. Space Marshals is a Sci-fi Wild West adventure taking place... | Read more »
Battle Slimes (Games)
Battle Slimes 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: BATTLE SLIMES is a fun local multiplayer game. Control speedy & bouncy slime blobs as you compete with friends and family.... | Read more »
Spectrum - 3D Avenue (Games)
Spectrum - 3D Avenue 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: "Spectrum is a pretty cool take on twitchy/reaction-based gameplay with enough complexity and style to stand out from the... | Read more »
Drop Wizard (Games)
Drop Wizard 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: Bring back the joy of arcade games! Drop Wizard is an action arcade game where you play as Teo, a wizard on a quest to save his... | Read more »

Price Scanner via MacPrices.net

14-inch M4 Pro/M4 Max MacBook Pros on sale th...
Don’t pay full price! Get a new 14″ MacBook Pro with an M4 Pro or M4 Max CPU for up to $320 off Apple’s MSRP this weekend at these retailers…they are the lowest prices available for these MacBook... Read more
Get a 15-inch M4 MacBook Air for $150 off App...
A couple of Apple retailers are offering $150 discounts on new 15″ M4 MacBook Airs this weekend. Prices at these retailers start at $1049: (1): Amazon has new 15″ M4 MacBook Airs on sale for $150 off... Read more
Unreal Mobile is offering a $100 discount on...
Unreal Mobile, an MVNO using AT&T and T-Mobile’s networks, is offering a $100 discount on any new iPhone with service. This includes new iPhone 16 models as well as iPhone 15, 13, and SE phones... Read more
16-inch M4 Pro MacBook Pros on sale for $250-...
Don’t pay full price! Amazon has 16-inch M4 Pro MacBook Pros (Silver or Black colors) on sale right now for up to $300 off Apple’s MSRP. Shipping is free. These are the lowest prices currently... Read more
Get a 14-inch M4 MacBook Pro for up to $240 o...
Amazon is offering a $150-$250 discount on Apple’s 14-inch M4 MacBook Pros right now. Shipping is free. Be sure to select Amazon as the seller, rather than a third-party seller: – 14″ M4 MacBook Pro... Read more
Clearance 14-inch M3 Pro MacBook Pros availab...
B&H Photo has clearance 14″ M3 Pro MacBook Pros (in Black or Silver) on sale for $500 off original MSRP, only $1499. B&H offers free 1-2 day delivery to most US addresses: – 14″ 11-Core M3... Read more
Sams Club is offering a $50 discount on Titan...
Sams Club has Titanium Apple Watch Series 10 models on sale for $50 off Apple’s MSRP. Sams Club Membership required. Note that sale prices are for online orders only, in-store prices may vary. Choose... Read more
Sunday Sale: Apple’s latest 13-inch M4 MacBoo...
Amazon has new 13″ M4 MacBook Airs on sale for $150 off MSRP right now, starting at $849. Sale prices apply to most colors and configurations. Be sure to select Amazon as the seller, rather than a... Read more
Apple’s M4 Mac minis on sale for record-low p...
B&H Photo has M4 and M4 Pro Mac minis in stock and on sale right now for up to $150 off Apple’s MSRP, each including free 1-2 day shipping to most US addresses. Prices start at only $469: – M4... Read more
Week’s Best Deals: 14-inch M4 MacBook Pros fo...
Don’t pay full price! These retailers are offering $200-$250 discounts on new 14-inch M4 MacBook Pros this week…they are the lowest sale prices available for new MacBook Pros: (1): Amazon is offering... Read more

Jobs Board

All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.