Creating Your First Jabaco Program


In this tutorial you could learn the elementary things to create software with Jabaco. Open the Jabaco IDE Documentation while reading this article will help you to understand some things much better. If you have enough experience with programming you should explore the language samples to get more detailed informations about the Jabaco language.

Contents

Intro

This short tutorial is an overview about Jabaco. It doesn't teach you programming. There are many good books with which you could learn software development. My personal recommendation:

Start Up

On the first start of Jabaco (after your registration) you are greeted by the "New Project"-dialog. In this dialog you have to choose the type of application you would like to create. For our first application we will select a "SDI Application".

Explanation:

SDI is an acronym for "Single Document Interface" and means that your application organzine each window as a single form. In opposite of that MDI is an acronym for "Multiple Document Interface" and means that your applications handles a list of "MDI-Child"-forms in the "MDI Parent"-window.

The "Open"-Button in the "New Project"-Dialog will create your new project and open the "Form Designer".


Form Designer

In Jabaco you have many graphical and non-graphical classes. You will find the most needed graphical user interfaces in the Jabaco ToolBox. Select the "Button"-control in the ToolBox and place it on the form. Now you could modify the look and feel of your new button by changing the properties. Search for caption and change it from "Command1" to "Test". Switch to the "Source Editor" with a double click on the new button in the GUI-Designer.

Source Editor

Jabaco create a new method "Command1_Click()" for you automaticly. The classic sample logic for the first program ist a "hello world". In a graphical application we could do that with a MessageBox. Sample:

Public Sub Command1_Click()
   MsgBox "hello world"
End Sub

If you would like to test your application you should start it with the integrated debugger.

Jabaco Debugger

Select "Project => Start" in the menubar, or press F5 to start your application in debug mode. If your applications works correctly you will receive a Window with a single Button "Test" which will open a message "hello world" on click. But mostly it isn't so easy and you have to debug or to test your software. Replace your sample with the following loop:

Public Sub Command1_Click()
   Dim i As Integer
   For i = -3 To 3
      Command1.Caption = i \ i
   Next
End Sub

This sample is very simple and if you think there are some statements you don't understand - don't worry. For now the only thing you have to know is: this sample will loop from -3 to 3 and execute the "Command1.Caption = i \ i" in every step. Press F5 and click on your "test"-button. You receive an Error "ArithmeticException / by zero" and the debugger stopped your application on the line where the error oncurs. Move your mouse over the "i"-variable will return you the current value. In this case the value is "0" and you try to make "0 \ 0". So the error is clearly, but maybe you have a logical exception in your software. In such cases you should stop the debugger with a breakpoint.

Breakpoints

On the left side in your "Source Editor" you have a small margin. Search the line in your source code you would like to stop and click at the left margin. Now you have a red point that mark the stop line. The debugger will suspend the execution on entering first command in the source line. As long as your software is suspended by the debugger you have the right to retrieve the value of a variable (move the mouse over the target variable) or to modify the source code. Press F5 to continue the execution. The program process all commands during the next breakpoint or the next exception. Press F8 to make a single step, that means the debugger will execute the line and stop at the next line.


Peroration

There are several ways to learn the development with Jabaco or with Java. Learning by doing is the preferred solution for the most developers. Read the sample source. Try to modify the examples and you will learn more methods step by step. Make your source code more sophisticated with design patterns. Read some articles about theoretical software development and you will have success with the powerful Jabaco Compiler.

Related

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This page has been accessed 17,859 times. This page was last modified on 7 November 2009, at 22:58.


This page has been accessed 17,859 times. This page was last modified on 7 November 2009, at 22:58.