IFIX-354

Intellut on

Educational Services

354 Student Guide

Using Visual Basic for Applications

with Intellution Dynamics iFIXVersion 2.1 - 7.99

Copyright 1999, Intellution, Inc.All Rights Reserved

Intellut on Student Information SheetName: _________________________________ Date: ____________________________

Title: __________________________________ Course: 354 v2.1-7.99

Phone Number: _________________________ Instructor: ________________________

Fax Number: ___________________________ Class Location: ___________________

E-mail: _______________________________________________________________________

Company Name and Address: _____________________________________________________

_____________________________________________________________________________

_____________________________________________________________________________

Hotel where you are staying: ______________________________________________________

1. Have you used any Intellution, Inc. products? Yes NoIf so, please note how long you have been working with the product(s):

FIX32 Software (FIX, FIX MMI, PlantTV) ________ Intellution Dynamics iFIX ________ Intellution Dynamics iBatch ________ FIX Paradym-31 ________

2. Have you ever attended an Intellution training class before today? Yes No

FIX Fundamentals (FIX 104) iFIX for New Users (154A) Advanced FIX (FIX 204) iFIX for FIX Users (154B) iBatch Basics (114) Advanced iFIX (254) Other

3. How did you learn about this training class?

Intellution Educational Services Course Catalog Intellutions web site Your local Intellution Representative or Distributor Other

4. Briefly describe your application: _______________________________________________

_______________________________________________________________________

_______________________________________________________________________

_______________________________________________________________________

For Office Use Only:

Cust: ______ SI: ______ Rep: ______

Dealer: ______ OEM ______ A&E: ______

Inty Emp: ______ Other (explain): _________________

Student Guide

Copyright 1999, Intellution, Inc. i

Intellution Dynamics iFIX Training _______________________________Version 2.1

Proprietary Notice

The manual and software contain confidential information which represents trade secrets of

Intellution, Inc. and/or its suppliers, and may not be copied or disclosed except as provided in thelicense with Intellution, Inc. The information in this manual is subject to change without noticeand should not be construed as a commitment by Intellution, Inc. Intellution, Inc. assumes noresponsibility for any errors that may be in this document.

1999, Intellution, Inc. All Rights Reserved.

Trademarks

1999 Intellution, Inc. All Rights Reserved. Intellution is a registered trademark. All productnames are trademarks of Intellution, Inc. All other names are property of their respectiveholders.

Microsoft Visual Basic Technology. 1996, Microsoft Corporation. All Rights Reserved.

Printed in the United States of America.

T h e I n t e l l i g e n t S o l u t i o n One Edgewater Drive, Norwood, MA 02062

Intellution Dynamics iFIX

Copyright 1999, Intellution, Inc. ii

Table of Contents _____________________________________________

Intellution Dynamics iFIX Training Student Guide

Days One and Two ................................................................................ x

Days Three and Four............................................................................. xi

Introduction........................................................................................... xii

1. Overview......................................................................................... 1-1

1.1. VBA Scripts........................................................................ 1-41.1.1. Understanding Objects .................................................. 1-61.1.2. Object Properties........................................................... 1-81.1.3. Object Methods............................................................. 1-101.1.4. Object Events ................................................................ 1-11

1.2. Container Objects................................................................ 1-121.2.1. iFIX Container .............................................................. 1-141.2.2. VBA and iFIX Container............................................... 1-16

1.3. VBA Code .......................................................................... 1-18

1.4. VBA Help........................................................................... 1-20

1.5. iFIX Automation Interface Help.......................................... 1-22

1.6. Key Terms .......................................................................... 1-26

1.7. Exercise 1 ........................................................................... 1-27

1.8. Summary Questions ............................................................ 1-38

2. VBA Environment.......................................................................... 2-1

2.1. Review................................................................................ 2-3

2.2. Visual Basic Editor ............................................................. 2-42.2.1. Project Explorer ............................................................ 2-62.2.2. Property Window .......................................................... 2-82.2.3. Immediate Window....................................................... 2-102.2.4. Code Window ............................................................... 2-12

2.3. Message Box....................................................................... 2-22

2.4. Input Box............................................................................ 2-24

2.5. Exercise 2 ........................................................................... 2-26


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Copyright 1999, Intellution, Inc. iii


3. Variables and Constants ................................................................ 3-1

3.1. Naming Rules....................................................................... 3-3

3.2. Variables .............................................................................. 3-43.2.1. Integers ......................................................................... 3-63.2.2. Floating Point................................................................ 3-73.2.3. String Data .................................................................... 3-83.2.4. Variant .......................................................................... 3-10

3.3. Declaring Variables .............................................................. 3-123.3.1. Variable Scope .............................................................. 3-163.3.2. Variable Lifetime .......................................................... 3-173.3.3. User Defined Data Types............................................... 3-18

3.4. Arrays .................................................................................. 3-20

3.5. Constants.............................................................................. 3-24

3.6. Variable Data in Pictures ...................................................... 3-28

3.7. Exercise 3............................................................................. 3-30

3.8. Summary Questions.............................................................. 3-45

4. Procedures and Functions ............................................................. 4-1

4.1. VBA References................................................................... 4-4

4.2. Procedures............................................................................ 4-64.2.1. Understanding Events.................................................... 4-104.2.2. Understanding Scope..................................................... 4-124.2.3. Procedure Arguments .................................................... 4-144.2.4. Expressions ................................................................... 4-18

4.3. Code Locations..................................................................... 4-224.3.1. Class Modules ............................................................ 4-24

4.4. Object Browser..................................................................... 4-28

4.5. The With Statement.............................................................. 4-32

4.6. Hints and Tips ...................................................................... 4-34

4.7. Exercise Example ................................................................. 4-36

4.8. Lab Exercise 4...................................................................... 4-38



Copyright 1999, Intellution, Inc. iv


5. VBA Debugging ............................................................................. 5-1

5.1. Review ................................................................................. 5-3

5.2. Customizing the VBE........................................................... 5-4

5.3. Introduction to Debugging.................................................... 5-6

5.4. Understanding Errors............................................................ 5-8

5.5. Debugging Tools .................................................................. 5-105.5.1. Stepping Through Procedures..................................... 5-125.5.2. Immediate Window .................................................... 5-145.5.3. Watch Window........................................................... 5-165.5.4. Quick Watch .............................................................. 5-185.5.5. Locals Window .......................................................... 5-205.5.6. VBE Calls Stack......................................................... 5-225.5.7. VBE Debug Floating Toolbar ..................................... 5-23

5.6. Style and Technique ............................................................. 5-24

5.7. Hints and Tips ...................................................................... 5-26

5.8. Lab Exercise 5...................................................................... 5-30


6. Introduction to Forms.................................................................... 6-1

6.1. Forms Overview................................................................... 6-3

6.2. Creating a Form.................................................................... 6-66.2.1. Form Controls ............................................................ 6-96.2.1. Adding New Controls................................................. 6-20

6.3. Launching the Form.............................................................. 6-22

6.4. Form Events ......................................................................... 6-23

6.5. Form Hints and Tips ............................................................. 6-24

6.6. Lab Exercise 6...................................................................... 6-25


Student Guide

Copyright 1999, Intellution, Inc. v


7. Controlling VBA Code................................................................... 7-1

7.1. Decision Statements ............................................................ 7-37.1.1. If Then Else................................................................... 7-47.1.2. If Then ElseIf ................................................................ 7-87.1.3. Select Case.................................................................... 7-107.1.4. GoTo............................................................................. 7-12

7.2. Looping .............................................................................. 7-137.2.1. Do Loops ...................................................................... 7-147.2.2. For Next Loop............................................................... 7-16

7.3. DoEvents ............................................................................ 7-18

7.4. Review of Layers ................................................................ 7-20

7.5. Lab Exercise 7 .................................................................... 7-24


8. Collections and Groups.................................................................. 8-1

8.1. Grouped Objects ................................................................. 8-38.1.1. ContainedObjects Property............................................ 8-48.1.2. ContainedSelections Property........................................ 8-68.1.3. Grouped Object Properties ............................................ 8-88.1.4. Group Events ................................................................ 8-10

8.2. Collections.......................................................................... 8-118.2.1. Pre-Defined Collections ................................................ 8-128.2.2. User Defined Collections............................................... 8-148.2.3. For Each Next Loop ...................................................... 8-19

8.3. Lab Exercise 8 .................................................................... 8-20



Copyright 1999, Intellution, Inc. vi


9. Embedded Objects ......................................................................... 9-1

9.1. WorkSpace Variable Objects............................................... 9-4

9.2. Timer Object....................................................................... 9-8

9.3. Event Object ....................................................................... 9-12

9.4. Scheduler ............................................................................ 9-16

9.5. Lab Exercise 9 .................................................................... 9-18


10. iFIX Automation ............................................................................ 10-1

10.1. iFIX Automation Reference ................................................ 10-3

10.2. iFIX Objects ....................................................................... 10-4

10.3. iFIX Subroutines................................................................. 10-6

10.4. Accessing the Process Database .......................................... 10-810.4.1. FindDataSource Subroutine ........................................ 10-10

10.5. Shell Function..................................................................... 10-12

10.6. Database Functions ............................................................. 10-14

10.7. Lab Exercise 10 .................................................................. 10-16


11. Error Handlers............................................................................... 11-1

11.1. Introduction to Error Handling ............................................ 11-3

11.2. Handling Basic Errors ......................................................... 11-6

11.3. Using an Error Handler ....................................................... 11-811.3.1. Procedure Based Error Handler .................................. 11-1211.3.2. Global Based Error Handler........................................ 11-14

11.4. VBA Error Codes................................................................ 11-16

Student Guide

Copyright 1999, Intellution, Inc. vii


12. Automation .................................................................................... 12-1

12.1. Introduction to Automation ................................................. 12-3

12.2. Adding References.............................................................. 12-4

12.3. Making the Connection ....................................................... 12-6

12.4. Creating an Instance of the Application............................... 12-812.4.1. Dim Statement using New Keyword........................... 12-1012.4.2. Set Statement.............................................................. 12-1112.4.3. CreateObject Function................................................ 12-1212.4.4. GetObject Function .................................................... 12-13

12.5. Example 1........................................................................... 12-14

12.6. Example 2........................................................................... 12-16

12.7. Lab Exercise 12 .................................................................. 12-18


13. ActiveX, Linking, and Embedding ................................................ 13-1

13.1. ActiveX .............................................................................. 13-3

13.2. ActiveX Basic Principles..................................................... 13-4

13.3. iFIX ActiveX Controls ........................................................ 13-6

13.4. VBA and ActiveX Controls................................................. 13-8

13.5. Installing ActiveX Controls................................................. 13-14

13.6. OLE.................................................................................... 13-16

13.7. Linking vs. Embedding ....................................................... 13-18



Copyright 1999, Intellution, Inc. viii


14. Accessing Relational Databases ..................................................... 14-1

14.1. Overview ............................................................................ 14-3

14.2. Data Access Objects (DAO)................................................ 14-613.2.1. Joint Engine Technology (JET) .................................. 14-813.2.2. ODBCDirect .............................................................. 14-913.2.3. Example Using DAO.................................................. 14-10

14.3. ActiveX Data Objects (ADO).............................................. 14-12

Course Appraisal Sheet

Appendixes

A. Glossary ........................................................................................... A-1

B. File I/O ............................................................................................. B-1

B.1. Opening a File..................................................................... B-3

B.2. Reading and Writing Data................................................... B-6B.2.1. Put Statement ............................................................. B-7B.2.2. Get Statement............................................................. B-8B.2.3. Input Statement .......................................................... B-9B.2.4. Input # Statement ....................................................... B-10B.2.5. Write # Statement....................................................... B-11B.2.6. Print # Statement ........................................................ B-12

C. Additional Notes .............................................................................. C-1

C.1. iFIX Object Methods .......................................................... C-2

C.2. Mathematical Functions ...................................................... C-5

Student Guide

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Copyright 1999, Intellution, Inc. x

Days One and Two ____________________________________________

Section 1 Section 5

Overview DebuggingIntroduction to VBA Understanding ErrorsiFIX and VBA Debugging ToolsContainer Objects Hints and TipsVBA Code and VBA HelpAutomation Interface Help

Section 6

Introduction to Forms

Section 2 Creating FormsVBA Environment Form Controls

Visual Basic Editor Launching FormsMessage Box and Input Box Form Events

Section 3 Section 7

Variables Controlling VBA CodeData Types Decision StatementsUser Defined Data Types If Then ElseArrays Case StatementConstants Loops

For Next LoopDo Loops

Section 4

Procedures and FunctionsProcedures Section 8Class Modules Collections and GroupsExpressions Grouped ObjectsFunctions Group EventsObject Browser User Defined Collections

Student Guide

Copyright 1999, Intellution, Inc. xi

Days Three and Four __________________________________________

Section 9 Section 12

Embedded Objects AutomationWorkSpace Variable Object Using AutomationTimer Object Adding ReferencesEvent Object Automation ExamplesScheduler

Section 13

Section 10 ActiveX, Linking, and Embedding

iFIX Automation ActiveXAccessing the Process Database iFIX ActiveX ControlsiFIX Subroutines VBA and ActiveX ControlsDatabase Functions Installing ActiveX Controls

OLE

Section 11

Error Handling Section 14Using Error Handlers Accessing a Relational DatabaseError Handle Examples Data Access Objects (DAO)VBA Error Codes ActiveX Data Objects (ADO)


Copyright 1999, Intellution, Inc. xii

Introduction __________________________________________________

Course DescriptionThis course is designed for those who wish to acquire a basic knowledge of Visual Basic forApplications (VBA) within the iFIX container. This knowledge will allow the student togenerate VBA based solutions for their special system requirements. The student should befamiliar with the iFIX workspace and its features. The course begins with an introduction toVBA and why VBA is so important in todays applications. Lectures, coding example, andlabs are included in this course on the important aspects of VBA, as well as reference toVisual Basic syntax. This course will demonstrate to the student how to enhance runtimeoperation to solve special problems. Additionally, the material will present information onadding custom design tools (like ActiveX objects) and adding online maintenance tools suchas operation manuals, part descriptions, and P&ID views.

AudienceThis course is principally designed for system integrators, instrumentation engineers andprocess engineers who want to use the power of VBA to create unique solutions for theirapplications in the process control industry.

Required Prerequisites

Completion of iFIX 154A or 154B is a must!

Familiarity with Microsoft Windows NT (Windows NT Explorer, Text Editor, etc.)

Working knowledge of process control applications.

Suggested Prerequisites

Familiarity with programming (especially Microsoft Visual Basic)

Course DurationFour (4) days.

Continuing Education UnitsThis course is worth 3.2 CEU credits.

Student Guide

Copyright 1999, Intellution, Inc. 1-1

1. Overview __________________________________________________

Chapter 1

Overview



1. Overview _________________________________________________

Section Objectives

This section provides an introduction to the VBA and the iFIX object Hierarchy. The studentwill run through a VBA sample application and discuss how objects are used within VBA. Thisincludes the following:

Introduction to Visual Basic for Applications (VBA)

VBA and iFIX

Understanding VBA Objects

Container Objects

VBA Help

iFIX Automation Interface

In addition, this section will also introduce important terminology used throughout the course.

Student Guide


1. Overview _________________________________________________

A. What is VBA?

VBA Microsoft Visual Basic for Applications

- an object-oriented and event-driven development environment thatsupports Microsoft forms and ActiveX

- usually referred as it is integrated into iFIX

- used throughout Microsoft products for customization

- Microsoft is licensing VBA as separate product

B. Terminology:

VB Visual Basic

- usually refers to Microsoft Visual Basic 6.0

- this is external to iFIX and VBA

VBA Microsoft Visual Basic for Applications

- included as a key component of Office 97

- VBA version number is 5.0 only for synchronization

VBE Visual Basic Editor

- editing environment for VBA

- accessible from Intellution WorkSpace

- exists in the applications included in Office 97

C. Differences between Visual Basic for Applications and Visual Basic

Visual Basic uses Visual Basic for Applications as its central code engine

VB allows the creation of executables and ActiveX controls

VBA allows you to customize and extend product capabilities

VBA creates script code and does not create executables or .DLLs



1.1. VBA Scripts _____________________________________________

A. Uses for VBA

Customize and extend an application, for example:

- add new dialog boxes and forms, add toolbar buttons

- automate tasks, control an application

- control e-mail and an Internet browser

Typical users of VBA could be OEMs, system integrators and end users

B. Using VBA scripts to manipulate objects

VBA allows the extending or customizing of applications by creating VBAscripts

VBA scripts will perform functions like calculations or other minor tasks but themain power of VBA will be to manipulate application objects

VBA scripts typically access an objects properties, methods, and/or events

VBA code created will be contained in an application as part of a project

Scripting in iFIX allows access to:

- standard VBA components

- all exposed iFIX objects and their properties, methods, and events

C. Within iFIX, use VBA to:

Animate objects in pictures

Create custom prompts and messages for operators

Read from, write to, and create database blocks

Incorporate custom security features

Automatically run other applications

Access other applications and manipulate their objects

Automatically generate pictures or objects

Incorporate and communicate with third-party custom ActiveX controls

Access ODBC data sources

Write custom wizards for frequently performed tasks

Student Guide


1.1. VBA Scripts _____________________________________________

VBA Terminology

Objects Comprised of data and procedures that are treated as a unit

Each object has its own properties, methods, and events that canbe used to write scripts

Examples: Rectangle, Timer, Schedule Event

Properties Characteristics of an object

Examples: color, size, location in the picture

Methods Subroutines that effect the behavior of object

Examples: such as scale or refresh

Events Actions that the object recognizes, such as when a user clicks themouse on the object or changes its size

If a script is associated with an event, the script executes whenthe event triggers or occurs

Events can occur as a result of user action, program code, or otheroccurrences in iFIX

Examples: mouse click, value reaches a threshold

Figure 1-1: VBA Terminology



1.1.1. Understanding Objects _________________________________

A. Notes

A VBA object is anything in the application that can be referenced andmanipulated

An object represents an element of an application, such as a worksheet, a cell, achart, a form, or a report

B. Examples

Common iFIX objects are:

- Rectangle, Oval, Text, Bitmaps, Pictures

- Figure 1-2 contains the iFIX objects that are available within VBA

Objects used frequently within VBA include:

- Forms, Collections, Applications

C. Additional Notes

The properties, methods, and events available for an individual object are basedon the object class

- Example:

rectangle objects have their own class

rectangle objects do not have the same font properties as text objects

Objects respond to events based on scripts that are written for each event

- scripts can be written for one event, some events, or all events, dependingon what needs to be accomplished

Student Guide


1.1.1. Understanding Objects _________________________________

Alarm Summary Application

Arc Bitmap

Chart Chord

Color Button ControlContainer

DataItem DataItems

DataLink DataServer

DataServers Document

Documents DynamoSet

Event ExpressionEditor

FindReplace FixDataSystem

FixFloatPoint Format

Group Group (DataSystem)

Groups Legend

Line Linear

Lines Lookup

Oval Pen

Picture Pie

Polygon Polyline

Procedures Rectangle

RoundRectangle Scheduler

ScriptLine ScriptProcedure

ScriptSource Sources

System Text

TimeAxis Timer

UserGlobals ValueAxis

Variable Window

Figure 1-2: iFIX Objects



1.1.2. Object Properties ______________________________________

A. VBA Object properties

Properties are the set of characteristics that define an object

- characteristics such as size, color, or screen location, or an aspect of itsbehavior, such as whether it is enabled or visible

To change the characteristics of an object, change the values of its properties

Examples: Properties can control the appearance and position of object

B. Viewing Object Properties

Use the Property Window within the WorkSpace to view the properties of anobject

- there is also a Property Window in the Visual Basic Editor to viewproperties of an object

Figure 1-3 shows some of the properties of a picture object using the PropertyWindow

C. Changing the property of an object

To set the value of a property, follow the reference to an object with a period, theproperty name, an equal sign (=), and the new property value

See Figure 1-4 for an example of changing an objects property

D. Additional Notes

Not all property values can be set by the user

The Help topic for each property indicates whether that property is:

- read-write

- read-only

- write-only

Student Guide


1.1.2. Object Properties ______________________________________

Figure 1-3: Properties Window Example

Private Sub Rect1_Click()

FermTank.BackgroundColor = vbBlue

End Sub

Figure 1-4: Property Scripting Example



1.1.3. Object Methods ________________________________________

A. VBA Object Methods

VBA can make the object perform a task by activating a method

A method is an action that an object can perform

See Figure 1-5 for an example of activating an objects method

Figure 1-6 shows examples of iFIX methods

Private Sub CFIXPicture_Initialize()

FermTank.FullView

End Sub

Figure 1-5: Method Scripting Example

Add BringToFront

Copy Connect

Enable FullView

GetCurrentValue InsertPoint

IsConnected Open

Refresh Rotate

ScrollForward SetWindowLocation

StopTimer Zoom

Figure 1-6: Sample iFIX Methods

Student Guide


1.1.4. Object Events _________________________________________

A. VBA Object Events

VBA allows you to define a procedure to be run when an event happens

Examples:

- the script in Figure 1-4 runs a procedure when a rectangle objects clickevent occurs

- the script in Figure 1-5 run a procedure when the picture initialize eventoccurs

Figure 1-7 lists the events available in iFIX

- note that not all events are available to all objects

Activated AfterKillFocus

AlarmAck Click

Close ColorChanged

DataChange DblClick

DeActivated Edit

EditChange Initialize

KeyDown KeyUp

LmouseClick MouseDown

MouseMove MouseUp

OnChange OnChartFull

OnChartRefresh OnFalse

OnPenSelect OnTimeOut

OnTrue RMouseClick

SelectionChanged UIDeactivate

WhileFalse WhileTrue

Figure 1-7: iFIX Events



1.2. Container Objects ________________________________________

A. Application Object

The object that is common to all applications and is at the top of the applicationmodel is the Application Object

The application object is the container for all other objects even other containerobjects like the Window object container

Application object has properties, methods and events of its own

- Properties like StatusBar, Caption, WindowState, and ActiveWindow

- Methods like CheckSpelling, Help, Quit, and EnableCancelKey

The iFIX application object is the WorkSpace

All iFIX objects like picture documents, shape objects and more will reside inWorkSpace

B. Window Object

Window object is also common in many applications

Window object is a container for the open document

Window objects has its own properties, methods and events

- Properties like Caption, Height, Width, and WindowState

- Methods like Activate, Close, LargeScroll and SmallScroll

iFIX Window object is part of the Picture document

C. Other Containers

VBA projects are also container objects

Each project can contain WorkSpace application objects, references, forms,modules and class modules

Student Guide


1.2. Container Objects ________________________________________

Figure 1-8: iFIX Object Hierarchy



1.2.1. iFIX Container _________________________________________

A. Intellution WorkSpace

The Intellution WorkSpace is the iFIX Container

- it is made up of objects and collections of objects

- this collection of objects is what makes up the iFIX application

The iFIX picture document is an object containing other objects

- User interface objects l like rectangles, polygons, chords, etc.

The iFIX picture document will also contain the VBA script code

B. Objects that are visible at runtime in the iFIX container:

Picture documents (.grf files that compose the screen view)

iFIX Scheduler documents

Fix2D objects (rectangles, text, lines, and such that make up a picture item)

Groups (named collection of shapes that form valves, pumps, tanks, etc.)

Objects that belong to a Collection

Data Link (datasource reference)

- this is actually a special type of the Text Objects

Animations (an embedded object attached to visible object)

ActiveX objects inserted to do a runtime function

- iFIX Alarm Summary object

- 3rd party controls

C. Intellution WorkSpace allows user interface objects to be manipulated

Object properties can be set at design time or with VBA script

Wizards and Experts are available to add VB scripts to the objects

iFIX Scheduler object creates script when it is configured

D. Intellution WorkSpace allows objects to connect to various datasources

iFIX process database , Historical files, Global variables, OPC servers and otherobjects

Student Guide


1.2.1. iFIX Container__________________________________________

Windows NT

NIC

Text

Modem

Serial Port

Hard Drive

Mouse

KeyboardiFIX Container

Picture Object

LineObject

RectObject

TextObject

Object Event VBA Code

Container Support Code

Excel Container

Workbook Object

Sheet1 Object

Sheet2 Object

XYZ Container

Form Object

Figure 1-9: iFIX Container



1.2.2. VBA and iFIX Container _________________________________

A. VBA within the container has access to different types of objects

iFIX objects

- Special features via scripting

- Custom database additions and deletions

- Objects that can be reusable across projects

Forms

- Allows for custom dialog boxes

- Allows for customizing design tools

ActiveX Objects

- Query special devices via ActiveX

- Perform a proprietary calculation

- View an AutoCAD DWG file

- Send a number to a pager or e-mail for technical support

OLE objects to provide seamless access to other applications

- Access/Excel for custom reports

- AutoCAD or Visio for special drawing

- Vendor supplied OPC driver for their device

Student Guide


1.2.2. VBA and iFIX Container__________________________________

B. VBA uses several items to perform its actions

Variables to keep track of values

- Can be many different data types

- Boolean, Integer, Real, and String are typical

Conditionals to determine if something is required or not

- Test for conditions

- Determine the state of an object

- Part of a calculation for which item next (sequencing)

Assignment statements to save results and set properties and values

- sets an object property to a value

- copies the result of a calculation into a variable

- copies an object property to a variable

System functions to provide for specified action to be done

- Predefined in the environment library

- One of an objects methods

- Examples (ClosePicture, CloseDigitalPoint, and MsgBox)

Decision statements to control which items are performed

- If statement - executes statements when it evaluates to True

- Otherwise, executes statements when the If evaluates to False

Looping statements to operate on sets of objects

- While loop executes statements when the conditional is True

- Do loop, same as While loop, but executes statements at least once

- For loop, same as While loop, but auto increments a variable each loop

User defined functions and subroutines to execute repetitive tasks

- Module of code (Visual Basic or Visual C)

- One of an object's methods

- Values can be passed into the subroutine to allow generalized operation

- Function is a subroutine that returns a value



1.3. VBA Code _______________________________________________

A. Where does VBA Code live?

In iFIX, each picture (*.GRF) is a VBA project

- creating a new picture in the Intellution WorkSpace (untitled1) will createa new project called Project_untitled1

- the picture document named untiled1 is included as part of that project

- the items that can be a part of the project are user forms, modules, andreferences

The VBA code within a project is contained within a module

- Modules, and all other supporting VBA components, make up a VBAproject

- in the VBE clicking on the Project_untitled will bring the module intoview in the code window of the VBE

Within a module, code is divided into procedures

- procedures are individual sections of code to perform a specific task

B. What else makes up VBA?

Already mentioned was the concept of modules, procedures and projects

Here is a partial list of topics and concepts that are a part of VBA and will bediscussed in the next chapters:

- Variables

- Constants

- Functions

- User forms

- Looping

- Decisions

- Debugging

- Expressions

- Automation

- Error Handling

Student Guide


1.3. VBA Code _______________________________________________

Figure 1-10: Visual Basic Editor



1.4. VBA Help _______________________________________________

A. Using the VBA help with routines

Source for what the functions do

Example of Points to code

Use table of contents, index, or find

B. Accessing the Help

Select from the Help menu

F1

C. Content Tab provides a table of contents for:

System functions and subroutines that provide access to predefined actions

Language Reference

MsForms Reference

Other Visual Basic Applications

D. Find Tab

Provides a matching list to every word in the Help file

Good for general information searches

E. Index Tab

Provide a match to keywords that the Help File developer decides was important

Index works like a book index for Help Topics

Student Guide


1.4. VBA Help _______________________________________________

Figure 1-11: VBA Help (Contents tab shown)



1.5. iFIX Automation Interface Help _____________________________

A. Tabs

Content - Table of Contents

Index & Find - search for topics by keyword

B. Contents

Objects, Properties, Methods, Events

Subroutines

Database Functions

Figure 1-12: iFIX Automation Help

Student Guide



Figure 1-13: iFIX Automation Help Alphabetical List




Figure 1-14: Automation Help Example (Rectangle Object)

Figure 1-15: Automation Help Example (Click Event)

Student Guide



Figure 1-16: Automation Help Example (ForegroundColor Property)

Figure 1-17: Automation Help Example (Rotate Method)



1.6. Key Terms ______________________________________________

VBA Terminology

Project Stores all VBA code and any added components: includesdocuments, code modules, class modules and form modules

Module Container in the VBE project that used to store VBA code

Procedure Unit of VBA code that performs a task or returns a value

Sub Procedure VBA Procedure that performs a task but does not return a value

Function VBA Procedure that returns a value

Container Container objects store other objects within. IntellutionWorkSpace contains Picture objects which contain shape objects

Constant Represents a numeric or string value that does not change

Variable Named memory space to store any type of data

Objects Comprised of data and procedures that are treated as a unit

Each object has its own properties, methods, and events that canbe used to write scripts

Examples: Rectangle, Timer, Schedule Event

Properties Characteristics of an object

Examples: color, size, location in the picture

Methods Subroutines that effect the behavior of object

Examples: such as scale or refresh

Events Actions that the object recognizes, such as when a user clicks themouse on the object or changes its size

If a script is associated with an event, the script executes whenthe event triggers or occurs

Events can occur as a result of user action, program code, orother occurrences in iFIX

Examples: mouse click, value reaches a threshold

Figure 1-18: VBA Terminology

Student Guide


1.7. ___________________________________________Lab Exercise 1

Introduction to VBA

Lab Exercise 1



_______________________________________________Lab Exercise 1

Lab Information

Upon successful completion of this lab exercise, you will be familiar with many terms relatedto VBA in iFIX. You will also be familiar with locating and manipulating various features inthe VBE, the Visual Basic Editor.

As you progress through this lab, you will:

Work with the help built into the WorkSpace and the VBE

Navigate through various dialog boxes in the VBE

Become familiar with VBE functionality and locations of options

When you are finished with this lab, turn to page 1-38 and answer the Summary Questions.

Resources:

The iFIX On-line Help and E-BooksThe iFIX Visual Basic Editor Help and iFIX Automation Help

Lab Information

During this section, you were introduced to VBA terminology, how to manipulate objects,how to create code, and how to use online help. Now you will get an opportunity to create apoint of reference for the future when youre confronted with VBA and iFIX terminology.

To give you some hands on experience with the Visual Basic Editor, we will guide youthrough various dialog boxes and windows. You will discover how to open various windowsand get details about the objects you are working with.

If you are looking for help remember that help can be found in the Electronic Books and theRelease Notes. There is also Automation Interfaces Help and Database Manager Help. Allof these can be found in the Help & Information folder of the WorkSpace System Tree. Andof course, if you go to the help menu you can get WorkSpace Help and Picture Help. Whenyou are working with the Visual Basic Editor, you have access to Microsoft Visual BasicHelp and iFIX Automation Help.

Student Guide


_______________________________________________Lab Exercise 1

A. A quick introduction to VBA.

Please be familiar with the answers to the following questions before continuing.

1. The VBA (Visual Basic for Applications) language is the same in all VBAapplications, from iFIX to AutoCAD to Visio to Microsoft Excel. So, for example,the VBA Editor in iFIX is the same as the VBA Editor in Excel. However, eachVBA implementation seems to vary. Why?

2. Can you use iFIX VBA to build a stand-alone application that can be complied downto an EXE, DLL, or OCX?

3. Since VBA is the same across all applications, you could take the VBA code and theUserForms you developed in iFIX VBA and drop them into Excel. Can you also takethe VBA code and UserForms you developed in iFIX VBA and drop them intoMicrosoft Access? How about Visual Basic itself?

4. In your own words, explain the following terms: properties, methods, and events.

5. Next to each term below, write down if it is a property, method, or event.

Color AddItem Layer VerticalPosition

FindObject Click KeyUp OnTimeOut

Name Edit BuildObject VerticalFillDirection

AddPen ClassName CurrentImage MouseMove



_______________________________________________Lab Exercise 1

B. Getting familiar with the Visual Basic Editor (VBE).

1. Create a new picture in the WorkSpace and add the following objects:

3 rectangles 1 oval

1 polyline 2 polygons

1 arc 1 pie1 chord 1 pushbutton

Your screen could look similar to this:

2. Save the new picture by clicking the File menu then Save.

Use the following file name:

VBAObjects

Student Guide


_______________________________________________Lab Exercise 1

3. You see all your new objects in the System Tree on the left-hand side of the

WorkSpace. You can see that all the objects have unique, though uninterestingnames.

4. Go to the View menu and select the Property Window.

The Property Window appears.

5. Note that when you select an object in the WorkSpace work area, the correspondingobject also is selected in the System Tree and in the Properties Window. You canalso select an object in the System Tree, or by using the drop-down menu in theProperties Window.

Regardless where you select the object (WorkSpace work area, System Tree, or

Properties Window) the corresponding information about the object is highlighted inthe other two locations.



_______________________________________________Lab Exercise 1

C. Edit the new picture

Now, we will go to the Properties window and make some changes so that you can seehow that affects your object in the work area.

1. Select one of the rectangles, Rect1 perhaps. Now, in the properties page, modify thefollowing properties:

Name: TankFillBarGraph

BackgroundColor: Yellow

Description: Ingredient Tank #1 Fill Bar Graph

EdgeColor: Dark Red

EdgeWidth: 4

FillStyle: Diagonal Crosshatch

ForegroundColor: Red

Layer: 1

RotationAngle: -10

The picture should now resemble the following:

The properties that you just modified in the Properties window can also be modifiedwith VBA code both at run-time (Run mode) and design-time (Configure mode).These same properties can have animations assigned to them.

Student Guide


_______________________________________________Lab Exercise 1

2. Take note of the Properties window. Select the pull-down menu and choose

VBAObjects. There are two things to note:

(a) You are looking at the properties page for the picture where you can leave adescription, comment, information about the author, etc.

(b) The picture object belongs to a class called CFIXPicture

3. Right click on the TankFillBarGraph object and select the Edit Script.

4. Now that you are in the VBE, go to the View menu and select Immediate Windowand Properties Window. Your display should look something like this:

5. The VBE should be displaying the Project Explorer in the upper left-hand corner.Below it should be the Properties Window. The lower right-hand corner should bethe Immediate Window and above it the Code Window. Above the Code Windowon the left-hand side is the VBE Object drop-down list. This is a list of objects thatare registered with the VBE. To the right of it is the Event drop-down list.



_______________________________________________Lab Exercise 1

D. Viewing the VBE Configuration

1. Go to the Project Explorer in the VBE, and highlight the Project_VBAObjectsproject.

2. Right click it and select Project_VBAObjects Properties from the menu. Youshould see the following dialog box. In the figure below we display both tabs.

3. Go to the Project Description field and enter the following:

This lab is hands-on VBE using Shape Objects

4. Now click the Protection tab. Do not change anything here, but be aware that youcan password protect your VBA code so other people can not access it. If someonewere looking at your picture in the WorkSpace and decided to look at your code bylaunching the Visual Basic Editor, they would get a prompt that forces them to type ina user and password.

5. Now, close the Project Properties dialog box by clicking the OK button.

Student Guide


_______________________________________________Lab Exercise 1

E. Additional VBE Functionality

1. Go to the Project Explorer and highlight the Project_VBAObjects project. Rightmouse click on it and select Insert from the menu, then choose Module.

The screen should now resemble the following:

You have just inserted a module called Module1. You can change the name in theProperties window.

2. When you look at your Project Explorer you will see VBAObjects located in the

WorkSpace Application Objects. This is where all your picture event code goes(this will be explained in more detail in the next chapter). In Modules, you will seethe module you just inserted, Module1. You can change the name to something moremeaningful. Also, you can have many modules.

In general, modules contain functions and subroutines called by the picture eventcode or by other functions and subroutines.



_______________________________________________Lab Exercise 1

3. Next we shift our attention to the Immediate Window. This window is great for

trying out functions and small bits of code. For example, if you want to know howmany days between today and the first day of the century, enter the following:

print DateDiff("d", Now, #January 1 2000#)

4. Finally, we bring our attention to the code window. Double-click on Module1 in theProject Explorer, and type the following code in the code window:

Public Sub Rotate10degrees()

With VBAObjects.TankFillBarGraph

.RotationAngle = .RotationAngle - 10

End With

End Sub

The screen should now resemble the following:

Student Guide


_______________________________________________Lab Exercise 1

5. Put your cursor on the word Rotate10degrees and press the key. If you madeany typos, you may have gotten an error message after hitting . If not, you justran your code.

6. Use to go back to the WorkSpace to see what changed. You should seethat the rectangle rotated 10 degrees.

The screen should resemble the following:

You were able to modify the properties of an object in the WorkSpace and theWorkSpace was not even in Run mode!

End of Lab Exercise



1.8. Summary Questions ______________________________________

1. What are all the different locations you can look to find help with iFIX objects?

2. Can you make changes to your Visual Basic Code while the WorkSpace is in run mode?Explain.

3. Is the property window in the VBE the same as the one in the WorkSpace?

4. iFIX is built upon Component Architecture. iCore is the glue in the Intellution Dynamicsfamily of software products. What are the main ingredients that make up our iCore glue?

5. In addition to shape objects, what other things are stored in the picture file (the GRFfile)?

Student Guide


2. VBA Environment___________________________________________

Chapter 2

VBA Environment



2. VBA Environment _________________________________________

Section Objectives

This section provides an introduction to the VBA environment. The discussion will includeVBA projects. The student will also use the Visual Basic Editor to create VBA script. Thisincludes the following:

Visual Basic Editor

Working in the VBE

Creating Procedures

Creating Modules

MsgBox and InputBox

Student Guide


2.1. Review__________________________________________________

A. Notes

Projects

- Open projects are a reflection of what is open in the WorkSpace

- In iFIX, each open picture (*.GRF) is a VBA project

- Creating a new picture in the Workspace (untitled1) will create a newproject called Project_untitled1

- Included in the project will be the picture document

- VBA code can reside as part of the picture document or in other areas suchas Modules, Class modules, and User Forms

- Picture documents, Modules, User Forms, and Class modules and all othersupporting VBA components, make up a VBA project

Code Modules

- Within the Visual Basic Editor the code displayed is the code module

- The code displayed can reside in a user defined Module, the PictureDocument, User Forms or a Class Modules

- Within a code module, code is divided into procedures

Procedures

- A self contained block of VBA code that performs a specific task orreturns a value

- To perform any VBA task a procedure must be written

- Every procedure has a name which must be unique within a module



2.2. Visual Basic Editor _______________________________________

A. There are multiple ways to access the VBE

From the Workspace menu, select Visual Basic Editor

From the WorkSpace, choose VBE button on toolbar

Right click an object that will contain script and select Edit Script

Use the Taskbar in the VBE to switch back and forth

B. Overview of the VBE Components

Project Explorer

- displays all the VBA projects currently opened in the WorkSpace

Properties Window

- displays the properties of the selected object

Code Window

- displays the code of the selected picture, module, or class module

Immediate Window

- used to test code functions without running an entire procedure

Student Guide


2.2. Visual Basic Editor _______________________________________

Project Explorer Code Window

Property Window Immediate Window

Figure 2-1: Visual Basic Editor (VBE)



2.2.1. Project Explorer _______________________________________

A. Project Explorer

Displays a list of open VBA projects

Open projects list reflects what is open in the application, for example,WorkSpace

- Each document in the WorkSpace is a project in the VBE

- Examples:

Pictures

Schedules

Toolbars

Globals

- this is important when communicating between pictures and otherdocuments

Projects contain open application objects (such as a picture), modules (if you havecreated them), and user forms you have built

Saving a project

- Projects can be saved by highlighting the project and selecting SaveProject from the File menu

- Also, when the application is saved, such as saving a picture inWorkSpace, the project will be automatically saved

Student Guide


2.2.1. Project Explorer _______________________________________

Figure 2-2: VBE Project Explorer



2.2.2. Property Window ______________________________________

A. The Property Window

Displays properties for highlighted object in Project Explorer

Includes the name of the property and the current property value

Properties can be shown alphabetically or by category

If property window is not shown, press F4 or select from View menu

New values can be typed in, selected from a drop down list, or double-clicked

Student Guide


2.2.2. Property Window ______________________________________

Figure 2-3: VBE Property Window



2.2.3. Immediate Window _____________________________________

A. Immediate Window

Used to test some code without having to run the entire project

Allows the developer to test expressions, execute code, change values, and debugan application

See Figure 2-4 for an example

- the ? is equivalent to the keyword print

From the View menu, select Immediate Window

- or press CTRL-G

Student Guide


2.2.3. Immediate Window _____________________________________

Figure 2-4: VBE Immediate Window



2.2.4. Code Window _________________________________________

A. Work (Code) Window

Displays the code modules and other objects such as user forms

To display the module code, highlight the project in the Project Explorer andperform one of the following:

- Double-click the highlighted project

- Select View Code from the Project Explorer menu bar

- Select Code from View menu

- Press F7

To display object-specific code in your project, highlight the object contained inthe project and perform one of the following:

- Double-click the object, such as a form

- Select View Object from the Project Explorer menu bar

- Select Object from View menu

- Press SHIFT-F7

B. Code Window Components

The code window is comprised of various pieces:

- Object list

- Procedure list

- Declarations section

- Procedure separator(s)

- Procedure(s)

Note: In some VBA books, the Object List and Procedure List are called theWizard Bar

C. Procedures

A self contained block of code is called a procedure

Two types of procedures:

- Sub Procedure

- Function Procedure

Student Guide


2.2.4. Code Window _________________________________________

Figure 2-5: VBE Code Window



2.2.4. Code Window _________________________________________

D. Object List

Pull down list that shows what objects exist for the highlighted project

Lists all objects associated with the module

Change code view mode from all procedures in module to only selectedobject procedure

- At the bottom left of window, select Full Module View or ProcedureView

A Group of objects is also an object

Includes (General) which refers to any procedures that are not associated with aparticular object

Example Objects

- Rect1

- Oval1

- Polygon1

- Group1

- CFixPicture

- Calendar1

Additional Notes

- If objects do not exist in the object list but are part of the picture

Right Click the object and select Edit Script

OR

From the Edit menu, select Select All and then right click EnableScripts

Student Guide


2.2.4. Code Window _________________________________________

Figure 2-6: VBE Object List



2.2.4. Code Window _________________________________________

E. Procedure List

Lists all procedures and functions in the module

- Pull down list to show available procedures for selected object

- Includes the event procedures

- List is different depending on Object type

- Event selection will position file to associated VBA code or create it

Object Event Examples

- Push Button Event

Click

- Mouse Events

Click, DblClick

MouseDown, MouseUp

MouseMove

- Key Events

KeyDown, KeyUp

KeyPress

- Initialize Event

- Enter Event

- Exit Event

- Activated Event

- De-Activated Event

Additional Notes

- Remember, the events that are available are object dependent

- Example:

Initialize event is available for an iFIX picture object but does notexist as an event for a rectangle object

Student Guide


2.2.4. Code Window _________________________________________

Figure 2-7: VBE Procedure (Event) List



2.2.4. Code Window _________________________________________

F. Function Procedure

Needs to be defined (needs a name) before it can be used

Definition ends with End Function

Definition can include parameters that may be passed to the subroutine

Function procedure typically does not modify its environment but does return avalue

G. Sub Procedure

Needs to be defined (needs a name) before it can be used

Definition ends with End Sub

Definition can include parameters that may be passed to the subroutine

Sub procedure is allowed to modify its environment but it can not return a value

Student Guide


2.2.4. Code Window _________________________________________

Function Celsius(fDegrees)

Celsius = (fDegrees - 32) * 5 / 9

End Function

Figure 2-8: Function Procedure Example

Private Sub CommandButton1_Click()

entry = InputBox ("Enter Temperature in Degrees F")

If entry = "" Then

MsgBox "No Value Entered"

Else

MsgBox "Temperature is " & Celsius(entry) & " Degrees C"

End If

End Sub

Figure 2-9: Sub Procedure Example



2.2.4. Code Window _________________________________________

H. Creating a new Procedure

From the Insert menu, select Procedure

- see Figure 2-10

Use this dialog to add a new procedure or function

Also, select the appropriate scope for the procedure

- defines the visibility of a procedure (or an object or variable)

- For example, a procedure declared as Public is visible to all otherprocedures in all modules within a project

- However, this is not true if Option Private Module is in effect

see the Help for more information on this

I. Creating a new Module

From the Insert menu, select Module

- the new module is added to the project

- the new module can be seen in the Project List window

New modules can also be imported

- from the File menu, select Import File

- the module to be imported should be a *.BAS file

- when a new module is imported, all the procedures of that module areimported

this may not be the desired result

to only add a particular procedure, open the *.BAS file in a texteditor and copy/paste the procedure into the VBA code window

use this same technique to copy sample code from the Help system

- existing VBA code can likewise be exported

Student Guide


2.2.4. Code Window _________________________________________

Figure 2-10: Add Procedure Dialog Box

Figure 2-11: Import File Dialog Box



2.3. Message Box ____________________________________________

A. Notes

Allows for message to be sent to the operator and waits for a reply

Displays a message in a dialog box, waits for the user to click a button, andreturns an Integer indicating which button the user clicked

Requires at least the string message as a literal

To specify more than the first named argument, use MsgBox in an expression

- to omit some positional arguments, include the corresponding commadelimiter

B. Syntax

MsgBox (prompt[, buttons] [, title] [, helpfile, context])

- prompt Required

string expression displayed as the message in the dialog box

- buttons Optional

numeric expression that is the sum of values specifying the numberand type of buttons to display, the icon style to use, the identity ofthe default button, and the modality of the message box

- title Optional

string expression displayed in the title bar of the dialog box

if the title is omitted, the application name is placed in the title bar

- helpfile Optional

string expression that identifies the Help file to use to providecontext-sensitive Help for the dialog box

- context Optional

numeric expression that is the Help context number assigned to theappropriate Help topic by the Help author

Student Guide


2.3. Message Box ____________________________________________

Figure 2-12: VBA - Help MsgBox Topic



2.4. Input Box _______________________________________________

A. Notes

Displays a prompt in a dialog box, waits for the user to input text or click abutton, and returns a String containing the contents of the text box

If the user clicks OK or presses Enter, the InputBox function returns whatever isin the text box

If the user clicks Cancel, the function returns a zero-length string ("")

To specify more than the first named argument, use InputBox in an expression

- to omit some positional arguments, include the corresponding commadelimiter

B. Syntax

InputBox (prompt[, title] [, default] [, xpos] [, ypos] [, helpfile, context])

- prompt Required

string expression displayed as the message in the dialog box

- title Optional

string expression displayed in the title bar of the dialog box

- default Optional

string expression displayed in the text box as the default responseif no other input is provided

if you omit default, the text box is displayed empty

- xpos Optional

numeric expression that specifies, the horizontal distance of the leftedge of the dialog box from the left edge of the screen

if xpos is omitted, the dialog box is horizontally centered

- ypos Optional

numeric expression that specifies, the vertical distance of the upperedge of the dialog box from the top of the screen

If ypos is omitted, the dialog box is vertically positionedapproximately one-third of the way down the screen

- helpfile same as MsgBox

- context same as MsgBox

Student Guide


2.4. Input Box _______________________________________________

Private Sub CommandButton1_Click()

response = MsgBox("Convert a Temperature?", vbYesNo, "Question")

If response = vbYes Then

entry = InputBox("Enter Temperature in Degrees F")

If entry = "" Then

MsgBox "No Value Entered"

Else

MsgBox "Temperature is " & Celsius(entry) & " Degrees C"

End If

Else

MsgBox "No Conversion"

End If

End Sub

Figure 2-13: MsgBox and InputBox Example



2.5. ___________________________________________Lab Exercise 2

Objects, Events, and VBA Code

Lab Exercise 2

Student Guide


_______________________________________________Lab Exercise 2

Learning Objectives:

Upon successful completion of this lab exercise, you will be more familiar with locating andmanipulating various features in the VBE, the Visual Basic Editor.

As you progress through this lab, you will:

Continue to work with the on-line help built into the WorkSpace and the VBE

Create new modules and new procedures

When you are finished with this lab, turn to page 2-35 and answer the Summary Questions.

Resources:

The iFIX On-line Help and E-BooksThe iFIX Automation On-line HelpMicrosoft Visual Basic On-line Help

Lab Information

During lecture you covered the VBA Editor and many of its settings and windows. This labwill give you some hands-on with the VBA Editor.

Note: Throughout the exercise, the following object naming conventions are used:

Prefix: What the object represents such as Pipe, Valve, Tank, PumpRoot: Properties of the object such as Color, Position, NumberSuffix: What type of shape was used such as Rectangle, Polyline, Bitmap

Common prefixes used: Valve Vlv, Pump Pmp, Header Hdr, Level Lvl,Mixer Mix, Temperature Tmp, Label Lbl, Pipe Pipe, Tank Tank or Tk,Reactor Rea, Conveyor Cnv, Packaging Station Pkg, Palletizer Plt

Common suffixes used: Group Grp, Polygon Pgn, Polyline Pln, Oval Ovl,Rectangle Rct, Rounded Rectangle Rrt, Bitmap Bmp, Text Txt, Line LinDatalink Lnk, Command Button Cmd, Chord Crd, Arc Arc, Pie Pie



_______________________________________________Lab Exercise 2

A. Creating a new picture with some simple objects

In the previous lab, you created many shape objects. You could see how they correlatedto the objects and properties in the Properties dialog box both in the WorkSpace and inthe Visual Basic Editor. With this lab you will see how the Event code in the VisualBasic Editor correlates to the objects in the WorkSpace.

1. Create a new picture in the WorkSpace and draw a rectangle, line, oval, polygon, andpolyline.

The picture should resemble the following:

2. Save this picture with the following name:

IngredientTank

Student Guide


_______________________________________________Lab Exercise 2

3. Using the Property Window, modify the properties of the objects as follows:

Rect1: Name: Tank1Rct

Description: Ingredient Tank#1

EdgeWidth: 4

ForegroundColor: Blue (16711680)

Line1: Name: PipeTk1ToVlv1Lin

Description: Tank #1 Pipe to Transfer Valve

EdgeColor: Black (0)

EdgeWidth: 9

Oval1: Name: Vlv1XoutOvl

Description: Valve #1 background

EdgeWidth: 4

ForegroundColor: Light Gray (12632256)

Polygon1: Name: Vlv1XoutPgn

Description: Valve #1 rotary-valve

EdgeWidth: 4

ForegroundColor: Dark Gray (8421504)

PolyLine1: Name: PipeXoutPln

Description: Transfer Out Pipe

EdgeColor: Black (0)

EdgeWidth: 9



_______________________________________________Lab Exercise 2

4. Next, make sure the center of rotation for your polygon is the actual center of the

polygon. To do this, click on the polygon to select it. Then, click the Object menufollowed by Rotate.

You will see the center of rotation and rotation handles appear.

5. If the center is not in the middle of the polygon, click on the center of rotation, and

while holding down the mouse button, drag the center of rotation to the center of thepolygon.

Center ofRotation

Student Guide


_______________________________________________Lab Exercise 2

B. Adding scripts to the picture

Add some scripts to change properties of the objects in the picture.

1. Right mouse click on Tank1Rct and from the menu, choose Edit Script.

You will now find yourself in the VB Editor.

2. Instead of working with the Click event, we want the MouseMove event, so from theevent drop-down menu, select MouseMove.



_______________________________________________Lab Exercise 2

3. You will now type the MouseMove event code as in the figure below. It is also goodprogramming practice to use comments, so you will be typing those in also, as yousee fit.

' Mouse-move event for the rectangle that represents our' tank. Any time you move the mouse over the rectangle, the' vertical fill value of the rectangle is decreased. The' tank is immediately refilled when it goes empty.

Private Sub Tank1Rct_MouseMove(ByVal Button As Integer, _

ByVal Shift As Long, ByVal X As Double, ByVal Y As Double)

With Tank1Rct

.VerticalFillPercentage = .VerticalFillPercentage - 1

If .VerticalFillPercentage < 1 Then .VerticalFillPercentage = 100

End With

End Sub

When finished, the code window should look something like the following:

Student Guide


_______________________________________________Lab Exercise 2

4. Next, use to go back to the WorkSpace.

5. Right mouse click on Vlv1XoutPgn and from the menu, choose Edit Script.

You will now be back in the VB Editor.

6. Again we do not want to put code behind the Click event, we want the MouseMoveevent, so from the event drop-down menu, select MouseMove. You will now typethe MouseMove event code as in the figure below adding comments as you see fit.

' Mouse-move event for the Polygon that represents our' Transfer out Valve. Any time you move the mouse over the' polygon, the rotation angle value of the polygon is' increased. The valve is immediately flipped back to its' original position when it goes upside down.

Private Sub Vlv1XoutPgn_MouseMove(ByVal Button As Integer, _

ByVal Shift As Long, ByVal X As Double, ByVal Y As Double)

With Vlv1XoutPgn

.RotationAngle = .RotationAngle + 5

If .RotationAngle > 180 Then .RotationAngle = 0

End With

End Sub



_______________________________________________Lab Exercise 2

C. Viewing the picture in Run Mode

1. Use to get back to the WorkSpace.

2. Save your work.

3. Go to Run mode to see what happens.

The picture should resemble the following:

End of Lab Exercise

Student Guide



1. In the iFIX object hierarchy, what object serves as the container for all shape objects andActiveX controls?

2. As you work with iFIX, you will see that each picture has its own VBA programmingproject. Is the VBA programming project a container object? What does it contain?

3. Explain the advantages of cutting and pasting code into a module versus importing anentire code module.

4. Suppose you create an object in a picture and then task-switch to the VBE. The objectdoes not appear in the Object List. What can you do to get the object to appear in theObject List?

5. Explain IntelliSense. What is it and how can it be used?




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Student Guide


3. Variables and Constants____________________________________

Chapter 3

Variables and Constants



3. Variables and Constants____________________________________

Section Objectives

This section provides an introduction to the concept of variables and constants in VBA. Thisincludes a look at variable data types, variable arrays, and constants. This includes thefollowing:

Variables

Variable Data Types

User Defined Data Types

Arrays

Constants

Student Guide


3.1. Naming Rules____________________________________________

A. Use the following rules when naming procedures, constants, variables, and arguments ina code module

The first character must be a letter as

Do not use a space, period (.), exclamation mark (!), or the characters @, &, $, #in the name

Names can't exceed 255 characters in length

Generally, dont use any names that are the same as the functions, statements, andmethods in VBA

- this will cause the keyword to be shadowed

- if the keyword is to be called in code, it will need to be referenced asfollows:

VBA.keyword

B. Notes

VBA is not case-sensitive, but it preserves the capitalization in the statementwhere the name is declared

Names within the same level of scope can not be repeated

- For example, two variables named tank within the same procedure can notbe declared

- However, a private variable named tank and a procedure-level variablenamed tank can be declared within the same module.



3.2. Variables________________________________________________

A. Used to store temporary values for use in later statements or calculations

Variables are declared using the Dim (dimension) statement

If you use a variable that has not been declared VBA will create it

- Not recommended practice

Typically a variable type and scope is included when declared

B. Scope of variable can be one of three types

Procedure level

- Only statements in the same procedure can access variable

Module level

- Statements in multiple procedures have access to variable

Public Scope

- Statements in different modules or projects have access to variable

C. The following is a list of variable data types and recommended characters usage

Boolean bool

Byte byte

Currency cur

Date dat

Decimal dec

Double dbl

Integer int

Long lng

Object obj

Single sng

String str

Variant var

Student Guide


3.2. Variables________________________________________________

Figure 3-1: Data Type Help Screen



3.2.1. Integers ______________________________________________

A. Use to represent whole numbers

Property values, like an objects border style

Modes like None, Slow, and Fast

B. Integer Data Types

Byte- 0 to 255, 8 bits/1 byte of memory

Integer (Short)

- -32768 to 32767, 16 bits/2 bytes of memory

Long- -2,147,483,648 to 2,147,483,647, needs 32 bits/4 bytes of memory

C. Defining

Dim ival as Integer for short or end with %

Dim lval as Long for long or end with &

Dim bval as Byte for byte

Use as constants, like 1, 10000, or -32

Student Guide


3.2.2. Floating Point _________________________________________

A. Use to represent numbers with fractional parts

Property values like screen position

Scaling factors

Two precision, single and double

B. Floating Point Data Types

Single- +/- sign (plus is assumed)

- 7 digit mantissa, with optional decimal point

- 2 digit exponential, optional 0 assumed

- 4 bytes of memory

from +/1.401298E-45 to +/-3.402823E38

Dim sval as Single for explicit declaration

sval! = 23.4 for implicit declaration

Use as constants like 1.45, 2.3E1, or 100!

Double

- +/- sign (plus is assumed)

- 15 digit mantissa, with optional decimal point

- 3 digit exponential, optional 0 assumed

- 8 bytes of memory

from +/-4.94065645841247E-324 to +/-1.79769313486232E308

Dim dval as Double for explicit declaration

dval# = 23.4 for implicit declaration

Use as constants like 1.45#, 23E1#, or -2.3E-1#



3.2.3. String Data____________________________________________

A. Notes

There are two kinds of strings: variable-length and fixed-length strings.

- variable-length string can contain up to approximately 2 billion (231)characters

- fixed-length string can contain 1 to approximately 64K (216) characters

B. String Concatenation

Use the & operator to build up a single string from several short ones

Example

- mystring = "initial text"

- mystring = mystring & " and more text"

- Displayed string would be "initial text and more text"

C. String Conversions

For string operations VBA does numeric to string conversions

Example

- mystring = object.name

- mystring = mystring & ":" & object.foregroundcolor

- Displayed string would be "object:255"

Student Guide


3.2.3. String Data _____________________________________________

Figure 3-2: Help - String Concatenation

Figure 3-3: Help - & Operator Example



3.2.4. Variant _______________________________________________

A. Variant type can hold all types of variables

If variable type is not declared it is considered a variant

Variants take more memory and must be converted to real type

- Good practice would be to provide variables with a type

Variant is only variable type that can contain a Null

- Null indicates that the Variant variable intentionally contains no valid data

Variant has its own unique default string value Empty

- The value Empty denotes a Variant variable that hasn't been initialized

- A Variant containing Empty is 0 if it is used in a numeric context and azero-length string ("") if it is used in a string context

- Don't confuse Empty with Null

B. Note

To determine the data type of a Variant value, use the VarType function

- See the Help for more information

C. Using the Variant Error value

In a Variant, Error is a special value used to indicate that an error condition hasoccurred in a procedure

- Unlike for other kinds of errors, normal application-level error handlingdoes not occur

- This allows the devel

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