Konstantin Goldobin

PowerBuilder has a very handy way to make data entry more convenient: the DropDownDataWindow and DropDownListBox edit styles for DataWindow columns. Indeed, it's much simpler to pick up a value from a look-up list than to type it in each time you need to enter it. However, it looks like we've overlooked one of the cases when use of a drop-down list can make data entry easier for the user. Most of the time we use drop-down lists when working with lists of pairs "encoded value"/"decoded value": the users see and select decoded values and encoded values are saved in the database. The data type of the columns for which we use drop-down lists in such cases may be either string or integer, but it doesn't make any difference in terms of defining the edit style. Another instance when drop-down lists come in handy is when there is a predefined list of all possible values th... (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 the past. For me, legacy code is code written by someone else no matter how long ago - 15 years or 15 minutes. What's common about all applications that were written by someone else? You don't kn... (more)

The Mystery of the dbName DataWindow Column Property

PowerBuilder has very good online help and documentation that extensively covers most aspects of programming with PowerBuilder. However, from time to time you'll come across a problem that you can't find an answer to in the online help or documentation. If a search on the Internet does not yield any results either, the only remaining option is to try to find the answer on your own. In this article I describe a problem I had with the dbName DataWindow column property and what I found out about it. How It All Started I was maintaining a project that had had no activity for quite a f... (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 we do text formatting inside a DataWindow column? Unfortunately, there's no way in the DataWindow object to do that. This article describes a technique that will let you simulate this. A Sample Da... (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 you can get more than simple data formatting. This article explores what you can do with DataWindow display formats demonstrating a few tricks. Using Regular Characters A DataWindow display format ca... (more)