Definitions

Lesson 1: Objects, Properties, Methods, Events

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In Lesson 1, we will cover some basic definitions essential to understanding programming, focusing on what a program is and how Windows programs differ from earlier methods of programming. We will discuss the key components of Windows programs such as objects, properties, methods, and events, with examples from Microsoft Calculator. You will learn what Visual Basic is, and how its programming environment combines a programming language with a graphical interface to make creating programs easier.

Navigation

Prev: Introduction
Next: Lesson 02

Keywords

, Visual Basic, program definition, properties methods events, Windows programming, event driven programming, GUI components, calculator app example, command buttons, text boxes, menu bar, programming environment, graphical user interface

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Intro

Transcript

As I mentioned in the introduction, we are going to skip a lot of the theory behind programming, but we have to start out with some basic definitions for what we are doing today.

First, what exactly is a program? The dictionary defines a program as a set of coded instructions that enables a computer to perform a desired sequence of operations. That is essentially all a program does. It performs a series of operations based on the instructions given to it by the computer programmer. That is you.

In the old days, the programmers actually had to program their stuff on punch cards, which I am sure was no fun. Then we had to type everything in on the keyboard line by line. That was no fun either. Then finally, Windows came along and made programming much, much easier.

Instead of typing in lines of code, Windows programs are made up of objects like command buttons that you push, text boxes that you type information into, menu bars that you can select functions from. Windows programs are not only easier to write, but they are easier to use.

Here is one of my favorite age-old Windows programs, Microsoft Calculator. It comes with Windows, and it illustrates many of the common components that you find in Windows programs.

Calculator has command buttons - these little buttons here that we can push. They will put numbers up here in this text box, or we can type the numbers right into the text box. There is a menu bar that allows us to pull down menus. Of course, we have our standard maximize, minimize, and close buttons.

The objects in Windows programs - the buttons, the text boxes - make programming and using the program much, much easier.

Windows programs and all the objects in them generally have properties, methods, and events. Properties describe the characteristics of a program or an object. For example, a button might have a height, a width, a color. Those all represent properties. This button right here, for example, is number nine, has a certain width and a height, and a color such as blue. Those are its properties.

Windows programs also have methods. Methods are built-in functions that the program performs. For example, when we start Calculator, it knows to pop a little zero here in the window and wait for user input. That is a built-in method.

Most Windows programs, if not all, have events. When those programs are event-driven, that means they sit around waiting for the user to do something, generating an event. If I click on this number nine, that generates an event inside the program. There is a little programming code underneath this button that we will see how to do today, that then puts a nine up here in this text box. That is called an event.

Properties, methods, and events make up the core of Visual Basic programming.

So what is Visual Basic? Visual Basic is a programming environment. It includes a programming language and a graphical user interface. The programming language allows us to enter in commands that the computer will execute. The graphical user interface allows us to create forms and buttons and text boxes, and the other things visually by clicking and dragging them with the mouse. The combination of the two provides an extremely powerful programming environment.

Quiz

Q1. What is a program, according to the dictionary definition?
A. A set of coded instructions that enables a computer to perform a desired sequence of operations
B. The part of the computer that stores information
C. A physical device used to interact with software
D. A random collection of files on a computer

Q2. What did programmers use to create programs in the earliest days?
A. Touchscreens
B. Punch cards
C. Wireless devices
D. Cloud software

Q3. How are Windows programs generally constructed compared to older methods?
A. By using objects like buttons and text boxes
B. By writing thousands of lines of assembly code only
C. By using only the command prompt
D. By assembling physical circuits

Q4. What is NOT an example of an object found in Windows programs?
A. Command buttons
B. Text boxes
C. Menu bars
D. Transistors

Q5. What do properties refer to when talking about program objects?
A. The functions an object can perform
B. The characteristics of a program or an object, like height or color
C. The errors an object can generate
D. The time a program takes to start

Q6. What are methods in the context of Windows programs?
A. Characteristics like color and size
B. Built-in functions the program performs
C. Menu options for the user
D. Physical parts of the computer

Q7. What is an event in Windows programming?
A. A user's action that triggers code to run
B. An error message from the system
C. The background color of the application
D. A new file created by the program

Q8. What does it mean when Windows programs are described as "event-driven"?
A. They run only at night
B. They wait for the user to perform actions and then respond
C. They run automatically without any user input
D. They generate random data for testing

Q9. Which of the following make up the core of Visual Basic programming?
A. Files, folders, and databases
B. Properties, methods, and events
C. Packages, modules, and forms
D. Variables, loops, and conditions

Q10. What is Visual Basic?
A. A hardware component that runs Windows programs
B. A programming environment that combines a language and a graphical interface
C. An anti-virus application for Windows
D. A word processing program

Q11. What allows for the graphical user interface in Visual Basic?
A. Writing everything in assembly code
B. Creating forms, buttons, and text boxes visually with the mouse
C. Using only keyboard shortcuts
D. Editing configuration files manually

Answers: 1-A; 2-B; 3-A; 4-D; 5-B; 6-B; 7-A; 8-B; 9-B; 10-B; 11-B

DISCLAIMER: Quiz questions are AI generated. If you find any that are wrong, don't make sense, or aren't related to the video topic at hand, then please post a comment and let me know. Thanks.

Summary

Today's video from the Computer Learning Zone is all about the basics of programming, and specifically Visual Basic. I want to get you started without bogging you down in a lot of detailed theory, but we do need to lay some groundwork with a few important definitions.

Let's start by defining what a program actually is. A program is simply a set of coded instructions that tells a computer what steps to take to complete a specific task. Everything a program does comes from these instructions, which are written by a programmer - in other words, by you.

Programming has come a long way since the early days. Programmers used to write their instructions on punch cards, which was a tedious process. Later, everything had to be typed in line by line at a keyboard, which was not much easier. Things changed dramatically when Windows arrived. Suddenly, programming was not just about writing lines of code, but also about creating and working with graphical components like buttons, text boxes, and menus. This shift made both developing and using programs much more user-friendly.

Let me give you an example with one of the classic Windows programs, Microsoft Calculator. This built-in calculator demonstrates many of the key features that Windows programs share. For instance, Calculator uses command buttons for numbers and operations, has a text box to display input and results, and includes a standard menu bar. You can input numbers either by pressing buttons or typing right into the text box, and you have your usual window controls to maximize, minimize, or close the program.

All those elements in a Windows application - buttons, text boxes, and menus - are called objects. Working with these objects makes it much easier both to build and operate software.

Now, every object in a Windows program has three main parts you should know about: properties, methods, and events.

Properties define the characteristics of an object. For example, a button is going to have properties such as height, width, color, and so on. If you look at the button labeled with the number nine, it has specific dimensions and a color. Those are just a few of its properties.

Methods are built-in actions or functions that an object can perform. For example, Calculator has a method to display a zero in its window after starting up, waiting for you to enter a number.

Events are what make Windows programs interactive. These programs are event-driven, which means they wait for you, the user, to do something. When you click the nine button, that action triggers an event inside the program. The event activates the underlying code, which then puts the number nine in the text box. This is what allows programs to respond dynamically to your actions.

These three aspects - properties, methods, and events - are fundamental to programming with Visual Basic.

So, what exactly is Visual Basic? Visual Basic is more than just a programming language. It is a full programming environment that includes both a language for writing instructions and a graphical interface for creating forms and interactive objects like buttons and text boxes. You build your programs visually by dragging and dropping objects with your mouse, and then you use the language to tell these objects what to do. This combination makes Visual Basic a very powerful tool for creating Windows applications quickly and efficiently.

If you want to see step-by-step instructions on everything we covered here, I have a complete video tutorial for you on my website at the link below.

Live long and prosper, my friends.

Topic List

Definition of a program
Evolution of programming methods
Introduction to Windows program objects
Common components of Windows programs
Explanation of properties in Windows objects
Explanation of methods in Windows programs
Explanation of events in Windows programs
Overview of event-driven programming
Introduction to Visual Basic
Features of the Visual Basic programming environment
Difference between programming language and graphical interface in Visual Basic

Article

Before you start creating programs, it is important to understand some core ideas. A program is simply a set of instructions that tells the computer what actions to perform. Think of a program as a recipe, where you, the programmer, write out each step the computer should follow to achieve a particular result.

In the early days of computers, programming was much more difficult. Programmers used punch cards to write their instructions, and later, they had to type every command by hand, line by line. These methods could be tedious and made it easy to make mistakes. Today, programming is much more accessible, especially with tools like Windows and Visual Basic, which let you design programs visually using objects such as buttons and text boxes.

When you use a Windows program like Microsoft Calculator, you interact with several objects. For example, the calculator is made up of command buttons, text boxes, and a menu bar. The command buttons are the numbers and operations you can click on, while the text box is where your numbers and calculations appear. The menu bar lets you access additional features. All of these objects make using the program straightforward and intuitive.

Programming in this environment is easier because you do not need to write everything from scratch. Instead of only typing lines of code, you can drag and drop objects like buttons and text boxes onto a form. These components come with properties, methods, and events.

Properties are attributes that describe what an object looks like or how it behaves. For example, a command button could have a height, a width, and a color. Imagine the number nine button on the calculator. Its properties would include how big it is, where it is placed on the form, and what color it displays on the screen.

Methods are the actions that an object or program can perform. These are like the built-in functions that make your program do things. For example, when you start the Calculator, it automatically shows a zero in its display area and waits for your input. That automatic behavior is an example of a method in action.

Events are a key piece of what makes Windows programs interactive. An event happens when you, the user, interact with a part of the program. If you click the number nine button, that generates a click event. Behind the scenes, some code linked to that event tells the calculator to display the number nine in the text box. Windows programs are event-driven, meaning they spend their time waiting for something to happen, responding when you interact with the interface.

The core of programming in Visual Basic is understanding how to use properties, methods, and events effectively to make your programs respond to what users do. Visual Basic itself is both a language and a programming environment. The language allows you to write instructions the computer understands, while the environment lets you create your programs visually by placing objects onto forms and setting up how they will behave.

For example, if you want to create your own simple calculator in Visual Basic, you would start by putting buttons and text boxes onto a form. Then you could write code for each button's click event. Here is what a sample event handler might look like in VBA when a user clicks a button labeled "9":

Private Sub btnNine_Click()
txtDisplay.Value = txtDisplay.Value & "9"
End Sub

This code tells the program to add the number 9 to the display text box each time the button is clicked.

By combining visual tools and code, Visual Basic makes it easier to design useful, interactive programs. Understanding and using properties, methods, and events is the foundation for building effective Windows applications, whether you are making a calculator or something much more complex.