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)
Have you ever seen a form that has its own microhelp that changes when a
field gets focus? I'm sure you have. You might see a window and at the bottom
of the window is a line that says, "OPTIONAL - Enter the employee birth
date," when a field is entered. We are going to create a simple automated
solution that will allow you to carry the microhelp along in the DataWindow.
Take a look at Figure 1. It's a freeform DataWindow with a SQL data source. I
chose the Employee table from the sample database that comes with
PowerBuilder. I didn't do anything special to it. My goal here is to ... (more)
In my last article we explored what I call Advanced DataWindow Sorting. We
covered everything that we need for the DataWindow. In this article we are
going to polish what we did last month and make it look professional.
The main area of concern is our sort selector window as seen in Figure 1. It
does the job. It's just amateurish and doesn't provide the full flexibility
that we really need.
You may recall that the text of the sortable column is specified in the tag
property of the column in the DataWindow. (huh?)
We open the sort selector window with a parameter, something like t... (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)