TweetFollow Us on Twitter

Selective Color
Volume Number:10
Issue Number:1
Column Tag:C Workshop

Related Info: Dialog Manager

Selective Color

Using custom color buttons on color and black and white Macs

By Mark W. Batten, Washington, D.C.

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

Custom color buttons enliven any application, but if the programmer is writing software that must run on both black-and-white and color machines (as most of us are), it may seem daunting to write code that will draw the button different ways on differently configured machines. This article demonstrates a simple scheme to create buttons that are smart enough to be custom-drawn on color machines, and as regular Toolbox buttons on black-and-white machines.

The key to the technique is the Toolbox routine SetDItem. Although generally used only to change a dialog item’s rectangle, SetDItem is actually quite powerful; it lets you change just about everything associated with a dialog item. In this example, we’ll use it to point the Mac to our own CDEF to draw the button on color machines.

Setting Up The Resources

First, you need to create the CDEF that draws the color button. At the end of this article is source code for a sample button with a nice 3-D appearance.

(This particular CDEF uses an “auxiliary control record” (as described in Inside Macintosh, Vol. 5, pp. 216-18) to tell it what colors to draw the control in. If you’ve never encountered these arcane things, don’t worry; you don’t need to understand them to implement the scheme described in the article).

Second, create a dialog (DLOG) and a dialog item list (DITL) for your application as you normally would. Be sure that your DLOG will not be displayed when it’s loaded (in ResEdit, be sure the “Initially visible” box is unchecked). The DITL should use normal, vanilla buttons for OK and Cancel. That way, the resource is all set up to run normally on black-and-white machine, without any more work.

For this example, you also need to create two other resources: a dialog color table (‘dctb’) and a control color table (‘cctb’). (The correct values for the sample are listed at the end of this article). The ‘dctb’ serves two functions here: first, when you call GetNewDialog to read in a dialog, the Mac will automatically make it a color dialog, based on a CGrafPort, if the Mac finds a ‘dctb’ with the same ID as the DLOG resource. Second, the ‘dctb’ colors the content area of the dialog, which makes our button look better. The CDEF uses the ‘cctb’ resource to determine what colors to use when drawing the custom button.

Making The Switch

On a black-and-white Mac, the dialog will perform as it’s supposed to, without any special code in your application. To do something fancier on color machines, your application just has to alert the Dialog Manager to use our custom CDEF instead of the standard one. Here are the necessary steps.

1. In your application’s initialization routines, load the CDEF resource and the cctb color table into variables, like this:


/* 1 */

 Handle myCDEF;  /* handle to our custom CDEF */
 CTabHandle CtrlCTab;/* handle to colors for our control */

 myCDEF=GetResource('CDEF',32); 
 CtrlCTab=(CTabHandle)GetResource('cctb',128);

2. When you’re ready to create the dialog, load it with GetNewDialog (or build it from scratch with NewDialog). Then call the following routine, which uses SetDItem to tell the Mac where to find our custom code. Pass the DialogPtr in d and the item number of the button you want to convert in i:

/* 2 */

ConvertToColorButtons(d,i)
DialogPtr d;
int i; 
{
 int j; 
 Handle tItem; 
 Rect box; 
 char n[31];

 GetDItem(d,i,&j,&tItem,&box);
 if(j==ctrlItem+btnCtrl || 
 j==ctrlItem+btnCtrl+itemDisable){
 SetCtlColor(tItem,CtrlCTab);
 (**((ControlHandle)tItem)).contrlDefProc=myCDEF;
 j&=127;
 SetDItem(d,i,j,tItem,&box); 
 }
}
 Here's the CDEF code.

pascal long main(var,CH,msg,par)
int msg,var;
ControlHandle CH;
long par;
{
 long l;

 l=0L;
 switch(msg){
 case 0: 
 doDraw(CH); 
 break;
 case 1: 
 l=(long)doTest(par,CH); 
 break;
 case 2: 
 doCalc(par,CH); 
 break;
 }
 return l;
}

doTest(par,CH)
long par;
ControlHandle CH;
{
 Point pt;

 pt.v=HiWord(par); 
 pt.h=LoWord(par);
 return (int)PtInRect(pt,&((**CH).contrlRect));
}

doCalc(par,CH)
RgnHandle par;
ControlHandle CH;
{
 par=(RgnHandle)((long)par&0x7FFFFFFF);
 RectRgn(par,&((**CH).contrlRect));
}

doDraw(CH)
ControlHandle CH;
{
 int j,k,*p;
 Handle tItem;
 Rect r;
 RGBColor rgb,rgb1,rgb2; 
 AuxCtlHandle ax;
 FontInfo inf;
 
 r=(**CH).contrlRect; 
 j=StringWidth((**CH).contrlTitle); 
 GetFontInfo(&inf); 
 k=inf.ascent+inf.descent;
 k=(r.top+r.bottom+k)/2;
 MoveTo((r.left+r.right-j)/2,k-inf.descent);
 DrawString((**CH).contrlTitle);
 GetAuxCtl(CH,&ax);
 
 p=(int *)&(**(**ax).acCTable).ctTable[0].rgb.red; 
 rgb.red=p[0];   /* 21845, 0x5555*/
 rgb.green=p[1]; /* 21845, 0x5555*/
 rgb.blue=p[2];  /* 21845, 0x5555*/
 rgb1.red=p[4];  /* 34952, 0x8888*/
 rgb1.green=p[5];/* 34952, 0x8888*/
 rgb1.blue=p[6]; /* 34952, 0x8888*/
 rgb2.red=rgb2.green=rgb2.blue=0xFFFF;
 
 PenSize(2,2);
 RGBForeColor(&rgb);
 MoveTo(r.right-2,r.top); 
 LineTo(r.left,r.top);
 LineTo(r.left,r.bottom-2); 
 RGBForeColor(&rgb2);
 MoveTo(r.right-2,r.top+1);
 LineTo(r.right-2,r.bottom-2);
 LineTo(r.left,r.bottom-2); 
 rgb2.red=rgb2.green=rgb2.blue=0;
 RGBForeColor(&rgb2);
 InsetRect(&r,2,2);
 FrameRect(&r);

 InsetRect(&r,2,2);
 if(!(**CH).contrlHilite){
 PenSize(1,1);
 RGBForeColor(&rgb);
 MoveTo(r.left,r.top);
 LineTo(r.left,r.bottom-2);
 PenSize(2,2); 
 LineTo(r.right-2,r.bottom-2);
 Move(0,-1);
 PenSize(1,1);
 RGBForeColor(&rgb1);
 LineTo(r.left+1,r.bottom-3);
 LineTo(r.left+1,r.top);
 LineTo(r.right-1,r.top);
 Move(0,1);
 rgb2.red=rgb2.green=rgb2.blue=0xFFFF; 
 RGBForeColor(&rgb2);
 LineTo(r.left+2,r.top+1);
 }
 else {
 MoveTo(r.right-2,r.top);
 RGBForeColor(&rgb);
 LineTo(r.left,r.top);
 PenSize(1,1);
 LineTo(r.left,r.bottom-3);
 PenSize(3,3);
 LineTo(r.right-3,r.bottom-3); 
 PenSize(1,1);
 Move(2,-1);
 RGBForeColor(&rgb1); 
 LineTo(r.left+1,r.bottom-4);
 LineTo(r.left+1,r.top+2);
 LineTo(r.right-1,r.top+2);
 }
 rgb2.red=rgb2.green=rgb2.blue=0;
 RGBForeColor(&rgb2); 
}

The values for the color table resources for the example are as follows:

The control color table (type 'cctb') has two entries. The part codes are just 0 and 1 (the CDEF doesn't really use these) and the colors are { 0x5555,0x5555,0x5555 } and { 0x8888,0x8888,0x8888 }.

The dialog color table (type 'dctb') must have five entries, with part codes of 0-4, and colors as follows: { 0xAAAA,0xAAAA,0xAAAA }, { 0x5555,0x5555, 0x5555 }, { 0,0,0 }, { 0,0,0 }, { 0,0,0 }.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Coda 2.5.11 - One-window Web development...
Coda is a powerful Web editor that puts everything in one place. An editor. Terminal. CSS. Files. With Coda 2, we went beyond expectations. With loads of new, much-requested features, a few surprises... Read more
Bookends 12.5.7 - Reference management a...
Bookends is a full-featured bibliography/reference and information-management system for students and professionals. Access the power of Bookends directly from Mellel, Nisus Writer Pro, or MS Word (... Read more
Maya 2016 - Professional 3D modeling and...
Maya is an award-winning software and powerful, integrated 3D modeling, animation, visual effects, and rendering solution. Because Maya is based on an open architecture, all your work can be scripted... Read more
RapidWeaver 6.2.3 - Create template-base...
RapidWeaver is a next-generation Web design application to help you easily create professional-looking Web sites in minutes. No knowledge of complex code is required, RapidWeaver will take care of... Read more
MacFamilyTree 7.5.2 - Create and explore...
MacFamilyTree gives genealogy a facelift: it's modern, interactive, incredibly fast, and easy to use. We're convinced that generations of chroniclers would have loved to trade in their genealogy... Read more
Paragraphs 1.0.1 - Writing tool just for...
Paragraphs is an app just for writers. It was built for one thing and one thing only: writing. It gives you everything you need to create brilliant prose and does away with the rest. Everything in... Read more
BlueStacks App Player 0.9.21 - Run Andro...
BlueStacks App Player lets you run your Android apps fast and fullscreen on your Mac. Version 0.9.21: Note: Now requires OS X 10.8 or later running on a 64-bit Intel processor. Initial stable... Read more
Tweetbot 2.0.2 - Popular Twitter client....
Tweetbot is a full-featured OS X Twitter client with a lot of personality. Whether it's the meticulously-crafted interface, sounds and animation, or features like multiple timelines and column views... Read more
Apple iBooks Author 2.3 - Create and pub...
Apple iBooks Author helps you create and publish amazing Multi-Touch books for iPad. Now anyone can create stunning iBooks textbooks, cookbooks, history books, picture books, and more for iPad. All... Read more
NeoOffice 2014.12 - Mac-tailored, OpenOf...
NeoOffice is a complete office suite for OS X. With NeoOffice, users can view, edit, and save OpenOffice documents, PDF files, and most Microsoft Word, Excel, and PowerPoint documents. NeoOffice 3.x... Read more

Rage of Bahamut is Giving Almost All of...
The App Store isn't what it used to be back in 2012, so it's not unexpected to see some games changing their structures with the times. Now we can add Rage of Bahamut to that list with the recent announcement that the game is severely cutting back... | Read more »
Adventures of Pip (Games)
Adventures of Pip 1.0 Device: iOS iPhone Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: ** ONE WEEK ONLY — 66% OFF! *** “Adventures of Pip is a delightful little platformer full of charm, challenge and impeccable... | Read more »
Divide By Sheep - Tips, Tricks, and Stre...
Who would have thought splitting up sheep could be so involved? Anyone who’s played Divide by Sheep, that’s who! While we’re not about to give you complete solutions to everything (because that’s just cheating), we will happily give you some... | Read more »
NaturalMotion and Zynga Have Started Tea...
An official sequel to 2012's CSR Racing is officially on the way, with Zynga and NaturalMotion releasing a short teaser trailer to get everyone excited. Well, as excited as one can get from a trailer with no gameplay footage, anyway. [Read more] | Read more »
Grab a Friend and Pick up Overkill 3, Be...
Overkill 3 is a pretty enjoyable third-person shooter that was sort of begging for some online multiplayer. Fortunately the begging can stop, because its newest update has added an online co-op mode. [Read more] | Read more »
Scanner Pro's Newest Update Adds Au...
Scanner Pro is one of the most popular document scanning apps on iOS, thanks in no small part to its near-constant updates, I'm sure. Now we're up to update number six, and it adds some pretty handy new features. [Read more] | Read more »
Heroki (Games)
Heroki 1.0 Device: iOS Universal Category: Games Price: $7.99, Version: 1.0 (iTunes) Description: CLEAR THE SKIES FOR A NEW HERO!The peaceful sky village of Levantia is in danger! The dastardly Dr. N. Forchin and his accomplice,... | Read more »
Wars of the Roses (Games)
Wars of the Roses 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: | Read more »
TapMon Battle (Games)
TapMon Battle 1.0 Device: iOS Universal Category: Games Price: $.99, Version: 1.0 (iTunes) Description: It's time to battle!Tap! Tap! Tap! Try tap a egg to hatch a Tapmon!Do a battle with another tapmons using your hatched tapmons! *... | Read more »
Alchemic Dungeons (Games)
Alchemic Dungeons 1.0 Device: iOS Universal Category: Games Price: $.99, Version: 1.0 (iTunes) Description: ### Release Event! ### 2.99$->0.99$ for limited time! ### Roguelike Role Playing Game! ### Alchemic Dungeons is roguelike... | Read more »

Price Scanner via MacPrices.net

Canon PIXMA MG3620 Wireless Inkjet All-in-One...
Canon U.S.A., Inc. has announced the PIXMA MG3620 Wireless (1) Inkjet All-in-One (AIO) printer for high-quality photo and document printing. Built with convenience in mind for the everyday home user... Read more
July 4th Holiday Weekend 13-inch MacBook Pro...
Save up to $150 on the purchase of a new 2015 13″ Retina MacBook Pro at the following resellers this weekend. Shipping is free with each model: 2.7GHz/128GB MSRP $1299 2.7GHz/... Read more
27-inch 3.5GHz 5K iMac on sale for $2149, sav...
Best Buy has the 27″ 3.5GHz 5K iMac on sale for $2149.99. Choose free shipping or free local store pickup (if available). Sale price for online orders only, in-store prices may vary. Their price is $... Read more
Apple now offering refurbished 2015 11-inch...
The Apple Store is now offering Apple Certified Refurbished 2015 11″ MacBook Airs as well as 13″ MacBook Airs (the latest models), available for up to $180 off the cost of new models. An Apple one-... Read more
15-inch 2.5GHz Retina MacBook Pro on sale for...
Amazon.com has the 15″ 2.5GHz Retina MacBook Pro on sale for $2274 including free shipping. Their price is $225 off MSRP, and it’s the lowest price available for this model. Read more
Finally Safe To Upgrade To Yosemite’?
The reason I’ve held back from upgrading my MacBook Air from OS X 10.9 Mavericks to 10.10 Yosemite for nearly a year isn’t just procrastination. Among other bugs reported, there have been persistent... Read more
Logo Pop Free Vector Logo Design App For OS X...
128bit Technologies has released of Logo Pop Free 1.2 for Mac OS X, a vector based, full-fledged, logo design app available exclusively on the Mac App Store for the agreeable price of absolutely free... Read more
21-inch 1.4GHz iMac on sale for $999, save $1...
B&H Photo has new 21″ 1.4GHz iMac on sale for $999 including free shipping plus NY sales tax only. Their price is $100 off MSRP. Best Buy has the 21″ 1.4GHz iMac on sale for $999.99 on their... Read more
16GB iPad mini 3 on sale for $339, save $60
B&H Photo has the 16GB iPad mini 3 WiFi on sale for $339 including free shipping plus NY tax only. Their price is $60 off MSRP. Read more
Save up to $40 on iPad Air 2, NY tax only, fr...
B&H Photo has iPad Air 2s on sale for up to $40 off MSRP including free shipping plus NY sales tax only: - 16GB iPad Air 2 WiFi: $489 $10 off - 64GB iPad Air 2 WiFi: $559 $40 off - 128GB iPad Air... Read more

Jobs Board

Global Deployment Project Manager, *Apple*...
…international landscape is paramount to drive innovation, compliance, competition of Apple 's strengths, and talent planning. Manages the process, logistics, and systems Read more
*Apple* MAC Support Services Subject Matter...
Title: Apple MAC Support Services Subject Matter Expert Location: Pleasanton, CA Type of position: Temporary Contract for approximately 6 weeks Tasks The tasks for the Read more
*Apple* MAC Support Administrator - Net2Sour...
…solutions customized to client needs including staffing, training and technology Title Apple MAC Support Administrator Location Belmont, CA Duration 6+ Month Job Read more
*Apple* Certified Mac Technician - Updated 6...
…and friendly, hands-on technical support to customers troubleshooting and repairing Apple /Mac products with courtesy, speed and skill. Use your problem-solving skills Read more
*Apple* MAC Support Services Subject Matter...
…the best talent to create a competitive advantage. Currently, we are seeking an Apple MAC Support Services Subject Matter Expert for a long term contract in Pleasanton, Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.