Jun 01 Cover Story
Volume Number: 17 (2001)
Issue Number: 06
Column Tag: Getting Started
REALBasic 3 - The Marriage of Old and New
by Erick J. Tejkowski
Old World Mac Development meets New World Features
Introduction
Coincidental with the release of Mac OS X, REALSoftware announced the latest edition of their popular programming environment — REALbasic 3. REALbasic, a visually based, object-oriented BASIC environment for Macintosh, has always amazed fans in the past. The latest version is poised to do the same. With the introduction of a new operating system like Mac OS X comes the need for applications — and lots of them. REALbasic gives you the chance to create such applications, while simultaneously affording you the opportunity to reach out to other platforms with minimal effort. This fact alone may reason enough to warrant looking into REALbasic, but REALSoftware has also loaded REALbasic with all kinds of other powers.
Something Old
REALbasic 3 continues along the path of earlier versions by providing an easy-to-use cross-platform visual programming environment for the Mac OS. The latest incarnation of REALbasic builds on previous versions (REALbasic 1 & 2), so you will be glad to know that your old code should transfer to REALbasic 3 without a hitch. All of the familiar commands, controls, and features are there for your instant programming gratification.
There are, however, a few changes you should note. For starters, adding a resource file to your project works just as it always has, but now it is quite a bit friendlier. Previously, you were required to give an external resource file the name Resources for it to be recognized in the REALbasic IDE. Now, you are not limited to one external resource file. Instead, you may simply add a .rsrc extension to any file and it’s fair game for inclusion in your project. Therefore, it is now possible to have multiple resource files in your REALbasic project. In the event that you mistakenly include multiple files with conflicting resources (i.e. the same type and number), REALbasic simply overwrites earlier resources based on the order in which they appear in the Project Window.
Another important function that carries over into the latest version of REALbasic is the Declare statement. The Declare statement permits you to access Macintosh and Windows Toolbox calls directly from you REALbasic code, something that once was only possible with a plugin. REALbasic 3 continues to give you this ability and ups the ante by additionally providing access to Carbon calls. This requires a few code changes on your part, but luckily, the transition is nearly painless. Whereas the Classic Mac OS toolbox calls relied upon an assortment of libraries, Carbon code typically relies strictly on one library: CarbonLib. Updating your toolbox calls for Mac OS X often merely entails a library name change. If the syntax of the Carbon call has changed from its Classic predecessor though, you will have to change it as well. (See Listing 1).
Here is what a sample routine might look like:
Listing 1: Declare statements in Classic Mac OS versus Carbon
The only difference between most Class Mac OS Toolbox calls and their Carbon counterparts is a simple library name change.
Declare Function SetSysBeepVolume Lib “InterfaceLib”
(Level as Integer) as Integer
Declare Function SetSysBeepVolume Lib “CarbonLib”
(Level as Integer) as Integer
Something New
In addition to updating existing features, REALbasic adds a host of new abilities. Some of these features ease the transition to Carbon, while others are there just to simplify your life and make the REALbasic experience more pleasant.
The IDE
REALSoftware has made some nice changes in the REALbasic IDE. For example, you may now save your REALbasic projects in one of three formats (see Listing 2).
Listing 2: REALbasic 3 File Formats
Save As enables you to save your REALbasic projects in one of a number of formats rather than only one like in earlier versions.
Standard Project — REALbasic 3 format
REALbasic 2.1 Project — Provides backward compatibility. Without this feature, you would have to
rebuild your projects if you ever wished to migrate back to REALbasic 2.1.
XML — A new format for REALbasic. The Project saves as an XML text file to encourage REALbasic tool
development.
Furthermore, REALbasic 3 adds a bit of automation by making the build process Apple-scriptable. This allows you to perform builds under the power of an AppleScript. Figure 1 shows the REALbasic AppleScript Dictionary.
Figure 1. The REALbasic 3 AppleScript Dictionary.
Continuing on the path to making your life easier, REALbasic 3 makes dramatic improvements to the Auto-completion feature. As you type, REALbasic presents you with a list of possible commands, objects, methods, and property names; usually by the time you have typed the second or third letter of the word (see Figure 2). As you type, you see ellipses appearing directly after the cursor. When this occurs, press Tab and a list instantly appears displaying REALbasic’s guess as to what you wish to type next. Select the one you want and hit Return. This is a gem for all those hunt-and-peck programmers out there.
Figure 2. The REALbasic 3 Auto-Completion Feature
The REALbasic IDE also has some subtle navigation enhancements worth mentioning. The Code Editor has been updated with a few interface widgets that help you get around the environment quicker. Located at the bottom left corner of the Code Editor (see Figure 3), four small buttons give you instant access to navigation functions. The first button opens the Window Editor belonging to the current Code Editor in which you are entering code. The second button lets you toggle between showing all events and only the event you are working with. The third button takes you back in time to the last place your cursor rested in the Code Editor. Like multiple undos (which REALbasic has), your cursor can continue traversing backwards in time. The fourth button, as you may have guessed, lets you go in the opposite (forward) direction.
Figure 3. The REALbasic Code Editor provides some navigation options.
Carbon
REALSoftware released the third version of REALbasic alongside another major product release — Mac OS X. This was no accident. Perhaps the biggest news about REALbasic 3 is the fact that it can now compile Carbon versions of your projects, often with little or no change to your existing code. Your applications gain protected memory, Core Graphics text drawing, and other Carbon technologies with no additional effort on your part. Figure 4 displays the new Build Dialog where creating Mac OS X compatible software is as simple as clicking on a checkbox.
Figure 4. The Build Dialog shows how easy it is to create Carbon applications — one checkbox!
Although most code works “as-is” in Carbon builds, there may come a time when you need to address some specific facet of Mac OS X development. For example, Declare statements often differ based on the intended target platform. (Classic Mac vs. Mac OS X vs. Microsoft Windows). To facilitate platform specific code with Mac OS X, REALbasic 3 adds the TargetCarbon directive. Listing 3 shows it in action.
Listing 3: Targeting Mac OS X code
The TargetCarbon preprocessor directive permits you to address Mac OS X — specific code.
#if TargetCarbon
Declare Function SetSysBeepVolume Lib “CarbonLib”
(Level as Integer) as Integer
#elseif
Declare Function SetSysBeepVolume Lib “InterfaceLib”
(Level as Integer) as Integer
#endif
The Shell Class is another great new feature available in REALbasic 3 for the first time. With it, you can perform command line functions within your own projects. This creates all kinds of possibilities for enterprising individuals to create GUI-based applications for those command-line shy Mac users out there (and believe me, they exist). For Microsoft fans, this feature also works on Windows (DOS anyone?). Figure 5 shows the Shell Class in action and the pictured example is available on MacTech’s ftp site.
Figure 5. The REALbasic Shell Object in action.
Executing a shell script is as easy as creating a new Shell Object and sending it the Execute command. Listing 4 shows how to list the current processes in an EditField.
Listing 4: Executing Shell Scripts
REALbasic 3 affords you the chance to execute shell scripts just as you do from the command line. This example lists the current processes and the corresponding PID number.
Dim myShell as Shell
myShell = New Shell
myShell.Execute “ps -x | awk ‘{print $1} {print $5}’ ”
if myShell.ErrorCode = 0 then
EditField1.Text = myShell.Result
end if
iDisk
REALSoftware has always been a very open company when it comes to pre-release software. They have always believed that user should be able to take advantage of bug fixes and feature additions as they progress. As such, it is wise to chase down the most recent version of REALbasic, as it is typically quite stable and often provides useful new functions. Prior to REALbasic 3.1b7, REALbasic was only available online directly from REALSoftware. Now, Apple is offering the latest download of REALbasic on iDisk. With iDisk you do not even need a web browser to gain instant access the latest version of REALbasic. Just mount iDisk on the desktop and find REALbasic in the Software directory. Now, that’s cool!
Something Borrowed
Existing REALbasic developers will be glad to know that it continues to support a vast collection of technologies, even within Carbon applications. QuickTime and AppleScript support are there like before, but don’t forget that REALbasic can take advantage of the many new features inherent to both of these technologies. Its like getting bonus features free!
Furthermore, REALbasic 3 supports MIDI, MP3, and MPEG files using Windows Media libraries now. Previously, you were required to use QuickTime. Despite QuickTime’s popularity, more Window’s users take advantage of the Windows Media Player technologies, so this feature is a welcome addition.
Something Blue
Everything is turning blue! No, you do not need a new pair of glasses, it is just the Aqua interface you are seeing. Along with Carbon compatibility, REALbasic makes the switch to Aqua painless. REALbasic 3 uses the Aqua interface under Mac OS X. It also permits you to build applications using the Aqua interface. This all happens transparently to the user. Build projects like you always have; they instantly acquire the Aqua interface when using Mac OS X. REALSoftware has made the transition to Aqua beautifully, although, on occasion, you may need to resize a button or two to deal with the different sized fonts on Mac OS X. Figure 6 shows REALbasic in all its Aqua glory.
Figure 6. REALbasic 3 is Aqua all over.
After the Honeymoon
REALbasic, like Mac OS X, is in a bit of a transitory state at the time this article was written. At this point, everyone is expecting an update to Mac OS X in the near future. REALSoftware is following a similar path by readying REALbasic 3.1. The Beta versions of REALbasic 3.1 are publicly available (see the URL list at the end of this article). Because Carbon is in a state of flux, REALSoftware recommends checking the Beta version of REALbasic should the REALbasic 3.0 version lack some feature you require. Keep in mind that Apple released the final Carbon libraries only shortly before the release of Mac OS X. Once it did, REALSoftware began revising REALbasic to reflect the changes therein. Thus, the Beta version of REALbasic 3.1 provides a glimpse into the latest work coming out of REALSoftware’s Austin offices.
Avoiding Divorce
Some programmers may be wondering what value there is in purchasing a programming environment like REALbasic when Apple gives away free tools with Mac OS X. This is a valid question, but not necessarily a good assessment of the situation. Although Project Builder is essentially free for Mac OS X users, it relies on the more complex Objective C and Java languages for all coding. It does not permit BASIC source code, an undeniably easy language to learn. Moreover, REALbasic provides the only cross-platform visual development environment on the Macintosh. Project Builder doesn’t do Windows! Finally, REALbasic also provides some features unavailable to Project Builder users. For example, REALbasic comes stocked with a database engine, a sprite engine, XCMD support, and more. Sometimes, you truly get what you pay for.
Conclusions
In this article, we took a brief look at the new and updated features of REALbasic 3. Although much of it appears similar to past versions, it is clear that much work has gone into its development. Not only does it make improvements to existing technologies, but it also manages to make it easier than ever to produce quality Macintosh and Windows software. Creating software for Mac OS X has never been easier either. REALSoftware made the transition as painless as Apple made the 68K to PPC change nearly a decade ago. All of your old code works just as it always did, but now on Mac OS X.
References
If you haven’t already registered for an iTools account, do so immediately! With the account you get a 20MB partition (called iDisk) that allows you to publish to the web directly from your desktop. You can download the latest version of REALbasic from it as well.
Erick Tejkowski is the author of REALbasic for Dummies published by Hungry Minds. You can reach him at etejkowski@mac.com.
