Richard (Rik) Brooks

Subscribe to Richard (Rik) Brooks: eMailAlertsEmail Alerts
Get Richard (Rik) Brooks via: homepageHomepage mobileMobile rssRSS facebookFacebook twitterTwitter linkedinLinkedIn

Top Stories by Richard (Rik) Brooks

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)

Extending SQLCA

We are going to create a bare-bones email object. Of course you can expand that in the future if you like, but for now, let's just create the functionality that we need. I start by creating a custom class. In case you aren't familiar with the process look at Figure 1. Let's start with an instance variable. N_cst_mailer Instance Variables private mailMessage io_mail_message // The message to send I made the instance variables private so let's write a couple of functions to populate our mail Message. We'll start with the TO. Note that the io_mail_message contains an array of objec... (more)

Automating Your DataWindow

Every programmer knows about the IF command. It's pretty much a fundamental part of the syntax of every computer language that has ever existed. I don't need to explain how it works. The DataWindow can't use the IF command though. It does, however, support an IF function. IF(expression, TRUE, FALSE) In its simplest form this means that if the expression evaluates to TRUE, then whatever statement you supply for the TRUE part is executed. If not then the FALSE part is. Let's begin with a simple example. Let's create a DataWindow that will show employee information. Here is the SQ... (more)

DataWindow Magic: Master_Detail Object

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)

Using the Tag Property – Part 1

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)