Release 10.1A: OpenEdge Development:
Progress 4GL Handbook

Advantages of the AppBuilder file format

You have seen that the AppBuilder applies a special format to the procedures it generates, regardless of whether they represent a graphical user interface definition or just procedural logic for your application. When you open any procedure created with the AppBuilder, it parses this special format, which includes some specially formatted Progress comments that it alone is expected to read, and identifies all the different sections of the procedure, including object definitions and internal procedures.

Scanning through a long procedure in a listing, or in an editor window, or even in the Code Preview window, doesn’t give you a very good overview of what the procedure does, how it’s put together, and what its contents are. By contrast, when you use the Section Editor, you get a consistent predefined format to your procedures, with only the parts you’re generally interested in shown to you for review or editing. You can get a proper listing of all the elements in the procedure, either all together by clicking the List button or grouped by Section type. You can also print individual sections from the Section Editor. You can print the entire file from the main menu.

The Section Editor provides shortcuts for inserting all manner of text into your procedure, under the Insert menu shown in Figure 5–4.

Figure 5–4: Section Editor Insert menu

The following options appear under the Insert menu:

Database Fields — Shows you a list of all tables and fields in your connected databases so you can verify field names you need to insert into a procedure.
Event Name — Brings up a list of all possible user interface events.
Procedure Call — Shows you a list of all internal procedures so that you can insert a RUN statement for one of them. (Also shown as the Insert Call button in the window.)
Preprocessor Name — Brings up a list of all the preprocessor definitions in the procedure.
Query — Brings up the Query Builder.
Object Name — Brings up a list of all fields, variables, and other objects in the procedure.
File Contents — Lets you insert the contents of an operating system file.
File Name — Lets you insert the name of a file (for example, in a RUN statement).

All these options are useful aids that can increase your productivity and accuracy as a programmer.

There’s one more extremely important reason to use the AppBuilder whenever possible. In the example you’ve worked with in this chapter, the AppBuilder generates 4GL code and manages its format in a source file. The AppBuilder can do much more than that. In conjunction with Progress SmartObjects, the AppBuilder can convert some kinds of procedures into data-driven application components, whose definitions are stored in a repository database and created from that data at run time, eliminating the need for procedural code altogether. This is part of a very advanced concept in OpenEdge development. Keep in mind that any procedure that is readable by the AppBuilder is in a better position to be converted to another useful form automatically, which won’t be the case with hand-written procedures.