Classy was recently purchased by Symantec and has been taken off the market. They have said that they will be rereleasing it at some point in the future, perhaps synchronized with other product releases. With the current Bedrock effort, and rumors of a Symantec C++ for Windows and a revised Think Class Library, there are a variety of scenarios one can imagine. Regardless, this article is probably a first in the history of computer journalism–a review of a "finished" product that has not yet been released. We thought you might enjoy it if for no other reason than to get a glimpse of what Symantec might have up its sleeve.
Classy is an object programming utility for use with Think C++ 6.0. It consists of a MacDraw-like view editor with an integrated code generator and a set of classes that implement view resources, stream I/O, and a variety of other useful extensions to the Think Class Library.
Once installed, Classy's 24 classes are at your service (see Classy Classes on the next page). They can be used in an existing application just like any of the TCL classes. The best way to use the new classes is to fire up the Classy view editor (also named Classy) and build an application. But first, let's take a look at a few of the key classes.
CStream CBufferedStream CHandleStream CFileStream
These classes provide the infrastructure necessary to implement Classy's object I/O system. Get and Put functions are provided for all the "standard" data types (like PutChar(), PutBoolean(), and so on) as well as handles and pointers. In addition, there are GetObject and PutObject member functions that operate on CObject and its descendants.
The real power of the stream extensions comes from a pair of new virtual member functions Classy adds to CObject: PutTo and GetFrom. As you might expect, these two functions form the basis of a system that greatly simplifies manipulating your document's data.
To make that job even easier, Classy has added CSaver, a subclass of TCL's CDocument. CSaver implements the all the basic document I/O functions (like OpenFile and DoSave) using CFileStream. It knows what to read or write by adding a new data member called "itsContents." This data member is a pointer to the document's contents. Obviously, most applications will have more than a single data object in their document. The trick is to define a root object with PutTo and GetFrom member functions that deal with the "real" data objects correctly. If you then define a correct PutTo and GetFrom for each of your data objects everything else will be automatic. If this sounds a little confusing, don't worry: the Classy manual is pretty good on this point.
There is a great deal more to creating a complete application and document, but I know that what you really want to hear about is the view editor.
Before leaping into the view editor, you need to tell Classy a little bit about the application you intend to write. By selecting the "Application…" item in the Edit menu you can give Classy the information it will need to generate code for you. This information includes an application ID that is used to generate unique identifiers, a copyright message that will be placed in each source file, and your application's signature and file types (the ones you faithfully registered with Apple using the "C/F Registration Requests" stack).
The first step of course is to create a new view. For those of us used to MacApp terminology, a Classy view is most often a window of some kind and what we would call subviews are called "panes." (This corresponds to the TCL class terminology.) All the window types you would expect are available including Alert, Dialog, Floating Window, and Tearoff Menus. Classy's tearoff menus are so easy to use I put two of 'em in my test application.
One special window is the "Main Window." In TCL, documents are associated with a single main window (rather than a list of windows as in MacApp). Classy makes this connection for you when you select "Main Window" as the type of window. When creating your main window you do need to be careful not to make the name too long. Classy will generate class names from what you enter and file names that are even longer. When the Symantec C++ compiler gets hold of those names and adds ".XSYM" you can end up over the 31 character limit (yes, it happened to me).
Once a particular window type is selected, its attributes can be edited by selecting the View Info menu item (see Figure 1-Main Window View Info). As you can see from the illustration, you can do quite a bit of customization. There are additional "info windows" for alerts and floating windows as well.
The tools in the floating palette are almost all self explanatory. A few are less than obvious however: the "Warning Icon" produces an icon button and the shadowed version yields a nifty multi-state button. The "thing" that holds an overlapping ellipse and square yields a picture button and its shadowed twin a multi-state version of the same. Multi-state buttons can have different graphics for on/off and hilight states).
Of course, virtually every object placed in a view will need a bit of tweaking before it's just right. Classy provides an interface to the data members of each pane that is similar to that used in Apple's ViewEdit (see Figure 3-Editing Data Members). When you need to go further, the Classes… menu item provides a dialog that gives you the ability to define new subclasses of existing classes. You can even define new data members for the class, and Classy will automatically generate the appropriate stream I/O calls so that your new classes will instantiate fully with no additional intervention on your part.
Menus are created and edited in a two layered process (see Figure 6-Editing Menus). First you select a menu to edit (back window) and then click the "Edit Menu Items" button (hidden in the illustration). The subsequent "Menu Edit" dialog provides all the tools necessary to make your menus look and perform as you want them to. Recall that when you create a command you specify the class that will handle it. When you create a menu item and specify its command you're all done. The connection has been made and there's an empty method waiting to be implemented. Buttons have commands associated with them in the same way.
This two layer approach means that both you and Classy are free to make changes at will and can do so without treading on each other's territory. This flexibility costs almost nothing at run time, and since it is administered by Classy there is virtually no "mind share" involved either.
After the code is generated you add it to your Think project in the usual way. The starter project comes with a "place holder" segment already set up for you. When the compiler finishes its job you'll have a complete working skeleton of your application. For what it's worth, the program I developed to test Classy took about two hours from the time I sat down to the first running prototype. That includes the interface, two tear-off menu palettes which worked perfectly from the start, and a few additional windows. Pretty darn productive if you ask me.
Stylistically, Classy's code is very similar to TCL. A big comment block containing a description of the class and copyright information (with your name) heads up each file. Additional comment blocks describing their use separate each method and two or three line comments regarding implementation act as place holders in empty methods. Although I have only a passing familiarity with TCL, I found Classy's code easy to understand and modify.
As you can probably tell, I really like Classy. Nevertheless, it is not completely without flaws (but hey, it's only version 1.06!). I came across a couple of small bugs, neither of which affected my project or the generated code in any way. The documentation, while adequate, has a lot of room for improvement. It is particularly frustrating for a new user to search through the program's menus for things that aren't there anymore or have changed name or location. Finally, Classy's user interface could use a bit of tuning up. I already mentioned that I was allowed to enter class names that would eventually result in illegal file names. And my favorite annoyance was the need to hit Cmd-L to edit a pane's data members. A simple double-click like everybody else uses would be nice.
In spite of a number of very minor flaws, Classy is an eminently usable, utterly indispensable tool for anyone who uses TCL. It is highly recommended.
