Lec1 Visual Programming

7/30/2019 Lec1 Visual Programming

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Visual Programming,Lecturer Zaynab Al Quraishy, M.Sc.1

Outlines of lecture 1

1.1 What is Visual Basic?

1.2 Significant Language features

1.3 Important terminologies

1.4 Graphic User Interface (GUI)

1.5 Creating the project 1.6 Visual Basic Resources


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1.1 What is Visual Basic?

Programmers have undergone a major change in many years

of programming various machines. For example what could be

created in minutes with Visual Basic could take days in other

languages such: as "C" or "Pascal". Visual Basic provides

many interesting sets of tools to aid you in building exciting

applications. Visual Basic provides these tools to make yourlife far more easier because all the real hard code is already

written for you.


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With controls like these you can create many applications which

use certain parts of windows.

For example, one of the controls could be a button. First createthe control on the screen, then write the code which would be

executed once the control button is pressed. With this sort ofoperation in mind, simple programs would take very littlecode. Why do it like the poor old "C" programmer who wouldhave to write code to even display a window on the screen,when Visual Basic already has this part written for you.


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Even though people tend to say Visual Basic's compiler is far

behind the compilers of Pascal and C, it has earned itself the

status of a professional programming language, and has almost

freed BASIC of the reputation of a children's language.

Overall you would class Visual Basic as a Graphics User

Interface(GUI). Because as you draw, you write for theprogram. This must always be remembered in any kind of

creation of a Visual Basic program.

All in all, VB is the preferred language of many future program

means. If you want to start programming Windows, and don'tknow how to start, give Visual Basic a shot.


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1.2 Significant Language features

Visual Basic is not only a programming language, but also a

complete graphical development environment. Thisenvironment allows users with little programming experienceto quickly develop useful Microsoft Windows applicationswhich have the ability to use OLE ( Object Linking andEmbedding ) objects, such as an Excel spreadsheet.

Visual Basic also has the ability to develop programs that can beused as a front end application to a database system, serving asthe user interface which collects user input and displaysformatted output in a more appealing and useful form than

many SQL versions are capable of.


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Visual Basic's main selling point is the ease with which it allows

the user to create nice looking, graphical programs with littlecoding by the programmer, unlike many other languages thatmay take hundreds of lines of programmer keyed code.

As the programmer works in the graphical environment, much ofthe program code is automatically generated by the VisualBasic program. In order to understand how this happens it isnecessary to understand the major concepts, objects and toolsused by Visual Basic.


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The term "Personal Programming" refers to the idea that, wherever

you work, whatever you do, you can expand your computer'susefulness by writing applications to use in your own job. PersonalProgramming is what Visual Basic is all about.

Using Visual Basic's tools, you quickly translate an abstract idea

into a program design you can actually see on the screen. VBencourages you to experiment, revise, correct, and network yourdesign until the new project meets your requirements. However ,most of all, it inspires your imagination and creativity.


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Visual Basic can and is used in a number of different areas, forexample:

Education

Research

Medicine Business

Commerce

Marketing and Sales

Accounting Consulting

Law

Science


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1.3 Important terminologies

Properties -- attributes of objects

Controls -- check boxes, list boxes, etc.

Forms -- windows that contain applications controls

Events -- messages or requests for service

Procedures -- operations or services include methods, functions, subroutines


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1.4 Graphic User Interface (GUI)

Graphic User Interface (GUI) comprises

Forms

Controls

Event-driven programming


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The Windows GUI

Text boxes

Frame

Labels

Option buttons

Check boxes

Command buttons

Image

Picture box


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Creating VB Applications

Create the interface

Set the properties

Write the code


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1.5 Creating the project

On the file menu click new project.

(or just click on create in the start page)

New project window will appear, this window ask you to name

your project. Type the project name then press ok button.

New project dialog


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Now on the screen you will see

Form1.vb tab beside start tab


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The Visual Basic development environment contains these

programming tools and windows, witho which you construct your Visual Basic programs:

o Menu bar

o Toolbars

o Visual Basic toolboxo Form window

o Properties window

o Solution Explorer

o Immediate windowThe exact size and shape of the windows depends on how your

system has been configured.


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1.6 Visual Basic Resources

1. Programming Tools

The location and purpose of the Visual Basic programming tools aredescribed in the following.

Menu bar Located at the top of the screen, the menu bar providesaccess to the commands that control the Visual Basic programming

environment. Menus and commands work according to standardconventions used in all Windows-based programs. You can usethese menus and commands by using keyboard commands or themouse.

Toolbars Located below the menu bar, toolbars are collections of

buttons that serve as shortcuts for executing commands andcontrolling the Visual Basic development environment. You canopen special-purpose toolbars by using the View menu Toolbarscommand.


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Windows taskbar This taskbar is located along the bottom of the screen.

You can use the taskbar to switch between Visual Basic forms as your

program runs and to activate other Windows based programs.

2. Properties Window

With the Properties window, you change the characteristics (property

settings) of the user interface elements on a form. A property setting is a

characteristic of a user interface object. For example, you can change thetext displayed by a text box control to a different font, point size, or

alignment. (With Visual Basic, you can display text in any font installed on

your system, just as you can in Microsoft Excel or Microsoft Word.)

Displaying the Properties Window

To display the Properties window, click the Properties Window button on

the toolbar. If the window is currently docked, you can enlarge it by

double-clicking the title bar. To redock the Properties window, double-

click its title bar again.


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Changing Property Settings

You can change property settings by using the Propertieswindow while you design the user interface or by using

program code to make changes while the program runs.

3. Solution Explorer (Project Window) A Visual Basic program consists of several files that are linked

together to make the program run.

The Visual Basic development environment includes a Project

window to help you switch back and forth between thesecomponents as you work on a project.


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4. Toolbox Controls

You use special tools, called controls, to add elements of a program

user interface to a form. You can find these resources in the toolbox,

which is typically located along the left side of the screen. (If the

toolbox is not open, display it by using the Toolbox command on

the View menu.) By using toolbox controls, you can add theseelements to the user interface


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5. Visible and Invisible Controls

When a Visual Basic program runs, most toolbox controls

operate like the standard objects in any Windows -based

applicationand they will be visible to the user. However, the

toolbox also contains controls that can be used to perform special,

behind-the-scenes operations in a Visual Basic program. The

powerful objects you create with these controls do useful workbut can be made invisible to the user when the program runs.

These objects can be used for:

Manipulating database information.

Working with Windows-based applications.

tracking the passage of time in your programs.

Lec1 Visual Programming

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