Builder Xcessory

Builder Xcessory (BX) is a mature, high-end, object-oriented-based UNIX GUI development tool for Motif and Java, released just over a year ago for use on Linux. Along with Code Fusion from Cygnus, BXPro won Linux Journal's “Editors Choice” Award for Best New Application: Software Development in 1999.

In addition to highly intuitive widget layout, BX allows the developer to:

Builder Xcessory is the finest X and Motif GUI development tool available today for OOD/OOP developers working in C/C++ and Java, with enterprise development tools in the works, including other GUI APIs. For application frameworks, it allows the use of ViewKit and a MotifApp-based C++ class system, in addition to straight C for those maintaining legacy applications.

ViewKit is ideal for C++ and Motif work, but for the platforms on which it is not currently available, the MotifApp-based C++ framework provided runs like a charm when used with either Motif or LessTif. I found this especially helpful while porting Motif applications to the Rebel NetWinder, since its ViewKit port is still in the works at the time of this writing. One advantage to using the free Lesstif libraries, when Motif is absent, is that source is compatible across all UNIX/Linux-based X11 platforms.

Running various window managers does not affect the operation of the builder, as it has the Motif libraries statically bound, which also means it can be run without having Motif installed at all.

The Linux version of BX does not mess around with licensing daemons, using an encrypted license string instead. As of this writing, BX is available on Linux for $250 US for the personal-use license.

In addition to the comprehensive hard-copy manuals, all documentation is installed locally in HTML format and is easily invoked from the help menu. The manuals also have complete tutorials, describing in detail the steps needed to make use of each feature of BX. Tutorial data files and example code abound, and updates are freely available via the ICS FTP and web site.

As with most other GUI builders, it takes very little effort to implement what is referred to as the façade design pattern.

Modeling a complex object in a class, providing simplified access functions or methods to control it, and then using the GUI interface to view it allows us to make use of the Model View Controller (MVC) concept. This means we could, at any time, convert our program to a CORBA-type distributed application. Simply by substituting a method invocation on a CORBA-based object from within our GUI's event response routine, referred to as callbacks in X parlance, we now have a modernized distributed application. Keeping our GUI only loosely coupled to the data means we have little or nothing to update when changing how the back end of our application is implemented.

BX is a true WYSIWYG GUI builder. It will allow you to add widgets and components to other widgets and components intuitively. As you build up the GUI, the design tree reflects the widget hierarchy. This is more intuitive than other systems, where a widget is added onto the design tree and the widget placement appears on the screen. It is much more natural to interact with the widgets directly without this level of indirection. BX will also interactively show what happens to the window contents as it is being resized, making manipulation of Motif's more complex container widgets a breeze to configure.

Figure 1. Illustration of widget constraint settings for a push button inside a form widget

Figure 2. Browser window with sample widget tree displayed

Figure 3. Sample GUI as it can appear in the builder

Each Motif widget has its own list of resources which can be set using the resource editor. This allows for setting resources not related to geometry, such as fonts, colors and various callbacks.

There are a number of options for displaying which resources are viewable. As can be done with all of the BX menu items, the “View” menu shown in Figure 4 has been “torn off” and displayed in its own window, making for a more efficient workspace. If the user has selected the “All resources” option, there can be more resources potentially available for viewing than what is easily scanned through. BX provides a resource finder that allows the user to enter a search string, and any resource containing it will be scrolled to and highlighted, as shown in Figure 5.

Figure 4. View Menu

Figure 5. Search for Word “font”