Normally I try to write applications on the DataWindow or Appeon but every
now and then I get a question that makes me sit back and say, "Huh?"
In this case the question concerns the PostOpen event. I've seen that event
named different things: ue_post_open, postOpen, post_open, ue_postOpen, etc.
It has, as far as I can see, always had post and open in the name of the
event. Further, just about every framework that I've ever seen has had that
event in the base window.
The question that I was asked was, "Why is that event there?"
The programmer wanted to know why there was code in the post open and why was
it not just put at the end of the open event? At first I was really confused
by the question. It was like he was asking me why do we have arrays? I just
couldn't imagine not knowing the answer.
Then it occurred to me that I learned the answer to that question from a ... (more)
One of the most useful custom objects that I've ever written is my
master_detail object. It holds a prominent place in my toolkit. This article
will take you through the steps of how to write one and in the process
de-mystify the object.
First we want something that looks like Figure 1. Selecting a row in the top
DataWindow will display the details in the bottom. I'm sure that you've seen
this kind of DataWindow and you've probably written many of them. The key
here is not to tell you how to write this but how to simplify every one that
you will write in the future. For our exam... (more)
This article provides a means of automating the sorting of DataWindows... not
just grid DataWindows as discussed in last month's article, but all
DataWindows, regardless of display format.
Bear in mind that we are writing programmer tools. When writing for
programmers we want to give the programmer the maximum number of options
while minimizing the programmer effort. In other words, default as much as
possible but allow the programmer to move beyond the defaults.
We have several action items to implement:
Do the housekeeping to get an application going Create a window for sorting.... (more)
I'm considering changing my emphasis in my column. Since speaking with some
people at Sybase I am convinced that PowerBuilder is poised for a mighty
comeback. The fact is that still today PowerBuilder is by far the most
productive development tool available. It eclipses all the rest. An
experienced PowerBuilder programmer is demonstrably more productive and can
finish tasks faster than C# or even VB.NET.
So why is .NET used by more companies?
Mine would just be a guess and in fact, the answer is irrelevant. I'm here to
tell you that Sybase is making an obvious push to regain some... (more)
Service objects were introduced for PowerBuilder at about the same time as
the PowerBuilder Foundation Classes. Much like the PFC, most programmers
found reasons not to use them. In this article we will reduce the complexity
of these objects and in so doing perhaps open a new world of efficient
objects that are easily maintained and understood.
This article is going to create a service object for the DataWindow. The idea
behind this object and others like it is to minimize the footprint of the
DataWindow. We want to minimize the amount of memory that the DataWindow
requires and ... (more)