Konstantin Goldobin

PowerBuilder Developer's Journal A picture is worth a thousand words. We all have heard this saying a countless number of times. But what if you don't understand what is drawn in the picture? I was approached once with a request to review requirements specifications for some module. The document contained a scheme that represented the place of the module within the system. The picture was mainly made of rectangles and arrows. The rectangles had labels and I figured out that they represented other modules in the system. But I couldn't understand the meaning of the arrows. When I asked the author about them, the answer was "Well, they are just arrows." After a pause, "They show that there's some connection between the modules" was added. Nowadays, the UML has become the d... (more)

Highlighting Selected Text in PowerBuilder DataWindow

Let's suppose that you have a search window where a user can enter a search string and get the list of text items matching this pattern. Ideally, the portions of text that meet the search criteria should be highlighted, for example, by text formatting. It could look like Figure 1. In PowerBuilder we have a great tool for searching and displaying information - the DataWindow. But how can w... (more)

Exploring DataWindow Display Formats

DataWindow display formats aren't a big secret. Most PowerBuilder developers use them to format numeric, date, time, and string values properly. Such display formats are usually straightforward and contain characters that have special meaning for a specific datatype like '#' for numeric values or '@' for string values. However, the DataWindow display format is a very powerful tool and yo... (more)

Getting Rid of Global Variables

It may seem as if PowerBuilder programmers are bound to use global variables. Even the PFC, which is said to be the most successfully designed object-oriented framework, requires the use of global variables. Is it something in the nature of PowerBuilder that makes us use them? I won't discuss whether it's good or bad to use global variables as enough has been said on this subject. Howeve... (more)

Working with Legacy Applications

When I was just starting my career in programming, I thought I would be creating new applications. And I did - I created a few applications from scratch. Maybe two or three of them. But for the most part what I've been doing is working with code written by someone else a while ago - legacy code. What is legacy code? You could define legacy code as ancient applications that were written in... (more)