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Glossary
Events result from some
sort of action, for example, pressing a button, typing something and pressing
return, etc. In Java, they are subclasses of java.awt.event.ActionEvent.![[Outside link]](images/out.gif){kind=small}
(The icon means that
this is a link that takes you outside this tutorial.)
People in different places working together as if they were in the same location.
Controls are reusable, predefined components used for visual programming. Controls serve as building blocks that can be quickly combined to create a working application.
This is a technique to allow operations that depends on the kind of request and the types of two receivers to be executed. The object that calls the method passes itself as a parameter to the receiver, and so the receiver can act differently depending upon the type of the caller.
Actions in the real world such as a mouce clicked or a key
pressed or actions in the graphical user interface (GUI)
such as a button pressed are called events in Java and are modelled by the
class java.awt.AWTEvent.
Event procedures are Visual Basic procedures that respond to events result and are automatically generated by the Visual Basic. The programmer adds code to respond to specific events. Only events that are relevant to a program need be coded.
This object-based programming (OBP) explains how to create
and use classes and objects. The key technologies are inheritance and polymorphism.
For example, see the inheritance in class java.io.Externalizable.
"Prefab parts" for software. Frameworks are collections of objects that you can put together with your own objects to make programs for a particular domain of applications, thus saving you the work of starting from scratch. For example, Visual Basic provides the framework for writing collaborative applications, so that you do not have to worry about all the nitty-gritty of setting up the communications and other issues common to all such collaborative applications. The framework lets you concentrate on working on your particular program needs.
The form is the visual portion where the program graphical user interface (GUI) will be displayed. This form is where the user enters data (called inputs) to the program and where the program displays its results (called outputs) for the user to refer.
A special software package is often required to "add" the graphical elements.
Graphical User Interface (GUI)
GUI components facilitate data entry by a program’s user and formatting or presentation of data outputs to that user. For example, in the Visual Basic window, there is a bar containing menus (File, Edit, View, etc.), called a menu bar. Below the menu bar is a set of buttons that each specify a task for Visual Basic to perform if you click them.
Graphics Interchange File, which is a widely-used image format. Many graphics programs can create and read GIFs.
Integrated Development Environment (IDE)
The IDE allows the programmer to create, run and debug Visual Basic programs conveniently. IDE has its own workspace, project explorer, property viewer, toolbox and message screen. Beneath this squeaky neat interface, lies a powerful code generation tool.
This is an object that you attach to a widget,
for example, a button. It listens for events that
happen to that widget and contains code to take some action based on that
event. For example, the listener for a button on a graphical
user interface (GUI) will contain code to do the work associated with
that button when the user presses the GUI button. In Java, listeners implement
the public interface java.util.EventListener.
Functions attached to objects. Also known as messages.
This kind of documentation is based on the assumption that
people work better when you let them explore and determine their own tasks,
rather than giving them step-by-step instructions. The documentation tries to
give you the minimal amount of information necessary and avoid distracting you
with extra information. It is based on the research of John Carroll and
Mary-Beth Rosson as detailed in The
Nurnberg Funnel: Designing Minimalist Instruction for Practical Computer Skill.
Patterns and Pattern Languages are ways to describe best
practices and good designs, and to capture experience in a way that helps the
reader to learn to reuse this experience. For a more detailed discussion, see
the Patterns Home Page.
Rapid Application Development (RAD)
The process of rapidly creating an application. RAD is a tool to speed up the development of an application. To be more precise, it involves less manual coding and more automated code generation.
The process of rearranging your classes and methods so that common code is more easily inherited or delegated to. Refactoring allows you to avoid duplicating code.
Hierarchies designed for implementation inheritance tend to have their functionality high in the hierarchy – each new subclass uses one or more methods that were declared in a superclass, and the subclass uses the superclass declarations. Hierarchies designed for interface inheritance tend to have their functionality lower in the hierarchy – a superclass specifies one or more abstract methods that must be declared for each class in the hierarchy, and the individual subclasses override these methods to provide subclass-specific implementations.
Visual Basic (VB) works in Microsoft Windows environment. VB programs are created in an Integrated Development Environment (IDE). Visual Basic (VB) is the world most widely used Rapid Application Development (RAD) language. VB is a distintive language providing powerful features, e.g. graphical user interfaces, event handling, access to WIN32 API, object-oriented features, error handling, structured programming and much more.
Microsoft Windows is a graphical user interface (GUI) developed in the late 1980s and the early 1990s, the natural evolution of BASIC was Visual Basic, which was created by Microsoft Corporation in 1991.
A graphical user interface object,
for example, a button, text box, etc.
Last revised: 19 January 2004 15:00
If you spot an error, please contact sbho@mmu.edu.my. In addition, please contact me if you find some aspects of this task is not explained clearly so that I can improve this documentation.