The Internet Encyclopedia (Volume 3)

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THEVISUALBASICUSERINTERFACE 611

Figure 1: The Visual Basic IDE.

into an executable form, again without leaving the devel-

opment environment.

The Visual Basic development environment opens

by displaying a dialog box containing three tabs: New,

Existing, and Recent. The New tab offers a wide variety of

templates that can be used to create different types of ap-

plications. These application types include the following:

Standard.EXE files: normal Visual Basic programs.

ActiveX.EXE files: programs that allow other programs to

access their data.

ActiveX.DLL files (Dynamic Link Libraries): collections

of functions and procedures which can be accessed by

other programs.

ActiveX Controls: controls that can be incorporated into

other programs.

Active Document.DLL and.EXE files: programs that can

work within a browser and can be distributed over the

Internet or an intranet.

Add-In files: files that can be added to the Visual Basic

programming environment to automate common and

repetitive tasks.

The Visual Basic Application Interface assists in con-

structing the user interface.

The Existing tab presents a standard Windows dialog

box for browsing through local and network folders. An

existing Visual Basic program can be selected for mod-

ification. The Recent tab lists programs that have been

recently created or modified (Harrington et al., 1997).

After a new or existing program has been selected,

the Visual Basic IDE appears. The IDE consists of sev-

eral panes that provide general information about the

program being developed. A workspace to enter and edit

code is also included. See Figure 1.

Form Layout Window

The Form Layout window is used to design the user inter-

face. Think of a form as a blank window ready to be filled

with controls. Visual Basic programs can contain more

than one window. Each window is created in a separate

form (Harrington et al., 1997). Controls from the Toolbox

are placed on the form by clicking the control, moving

onto the form, and dragging a box open. Releasing the

mouse button places the selected control on the form in-

side the drag box. The control is automatically sized to

fill the box. SeeCreating a Program in the Visual Basic

Integrated Development Environmentsection later in this

document for specific examples of placing controls on a

form.

Code Window

Placing the controls on the form merely creates the inter-

face. Blocks of Visual Basic statements, called code, must

be added to the appropriate event handling procedures to

make the program respond to the event properly. Visual

Basic code is entered in the Code window.

Toolbox

The Toolbox displays icons that represent the various con-

trols that can be placed on a form. The Toolbox does

not automatically display all possible controls. Additional

controls are available from within the Visual Basic envi-

ronment and can also be obtained from third-party ven-

dors. These additional controls provide greater function-

ality, which can decrease development time (McKeown,

1999).