VB Environment Controls Code Working Environment

1
VB EnvironmentControlsCodeWorking Environment
chapter
ONE/TWO
2
Getting Started with Visual Basic

• Double-click VB icon on Desktop or use
  StartProgramsMicrosoft Visual Basic
  6.0Microsoft Visual Basic 6.0 to bring up New
  Project dialog box

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VB Development Environment

• Start in the Standard EXE environment
• The Project Window should have a white background
• Form should be displayed in Project Window
• Maximize Project Window

4
VB Development Environment
Form Size
Toolbar
Project Explorer
Initial Form Window
Toolbox
Properties Window
Project Window
Form Layout Window
Sizing Handles
5
Project Explorer Window
View code
View Object
Change Folders
Used to select the code or object or to change
folders.
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The Toolbox
Label Control
Textbox control
Used to select a control to place on form.
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Adding a Control

• Double-click to add control to center of form
• Can be moved around from there
• Use sizing handles to change size
• Single Click and draw (drag) on form
• Copy and paste (be sure not to make Control Array
  - until later)

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The Properties Window
Window Name
Object Box
Properties List Tabs
Scrollable list of properties
Description Pane
Used to change the properties of controls at
design time.
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Important Properties

• Name property identifies the control within the
  project (user doesnt see)
• Begins with a three-letter prefix
• lbl for label
• txt for text box
• frm for form
• Can include letters, numbers
• txtTextBoxToEnterInfo
• Caption property what user sees on screen

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Textbox

• Use when you want user input
• prefix txt
• Properties
• Text actual text
• Alignment center, left, right
• Multiline true, false
• Example
• txtMessage.Text This is my story.

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Checkbox

• Two options
• Checked True
• Unchecked False
• prefix chk
• Multiple checkboxes may be checked
• Properties
• .Caption actual text
• .Value (default)
• 0 unchecked
• 1 checked
• 2 grayed (unavailable/disabled)

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Option Button

• Presents list of options to user
• Prefix opt
• Choices are mutually exclusive
• Properties
• .Caption actual text
• .Value true/false

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Frame

• Contains sets of checkboxes and option buttons
• prefix fra
• Properties
• .Caption name of frame
• HINT If you want to associate option buttons,
  then draw and place frame before instantiating
  the buttons. Options within a frame (or form) are
  a group within that object.

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Image

• Places images on your form
• prefix img
• Allowable image formats are
• jpg, gif, bmp, ico, etc..
• Properties
• .Stretch true / false (image sized to image
  box)
• .Visible true / false

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Adding Code to Project

• Code goes in Code Window in event procedure
• Event procedure begins with Private Sub and
  ends with End Sub
• First Visual Basic Statements -
• End
• lblExample.caption some text
• PrintForm

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Design Time and Run Time

• You are in Design Time when you are designing
  the project and adding code
• You are in Run Time when you click the Play/Run
  icon
• You can stop the project and exit Run time by
  clicking the Stop icon
• You can go to Break Mode by clicking the Pause
  icon

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Files in Visual Basic

• All projects in VB have a .vbp (project) file and
  at least one .frm (form file) file.
• To Save
• FileSave Form As
• FileSave Project As
• Use Save (Disk) icon for periodic saves
• Projects with graphics (and some special text)
  also have .frx (binary form) files.
• Saved automatically
• Module files have a .bas extension and are pure
  code files - no controls or form.
• FileSave Module As

18
Review
A B C D E
F G H I J
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Graphical User Interface Issues

• What are some ways or things you/user would
  expect in a program?
• Make things visible
• Minimize required interactions(keystrokes/clicks)
• Anticipate event order
• Good screen design
• What are some issues (technical/human) with
  screen design?

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Graphical User Interface Issues

• Keyboard Access
• programmer defined
• Ampersand () identifies accelerator key
• Exit will underline the x and make it the
  accelerator key - ALT plus accelerator key
• Tooltips
• onscreen, pop-up help
• Property
• .ToolTipText actual text

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Graphical User Interface Issues

• Form Startup Position
• .StartUpPosition 2 (center)
• Tab Order - the order in which the user visits
  the commands on the screen using the tab key
• based upon concept of focus, TabStop, TabIndex
• focus - the object currently active - SetFocus
• TabStop - whether or not the Tab key stops here
• TabIndex - the Tab rank of a particular object

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TabStops and TabIndex
Label TextBox TabStop
NA TabStop True TabIndex 0
TabIndex 1
Name
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Graphical User Interface Issues

• Command Button Properties
• .Default
• true / false
• Assign the command button event that will be
  executed if ENTER is pressed.
• .Cancel
• true / false
• assign the command button event that will be
  executed when ESC is pressed

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Coding Issues

• VB tracks properties associated with Objects and
  provides pull-down menu of available properties
• VB has a short cut for assigning multiple
  properties of the same object
• With ObjectName
• .Property
• .Property
• .Property
• END With
• Shortcuts provide some efficiency in code, mainly
  documentation

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Coding Issues

• Dealing with text
• Adding text together is called concatenation
• VB uses (Ampersand) in code to add (join) two
  sets of text together.
• Example
• txtMyFirstName.text Josh
• txtMyLastName.text Goshen
• txtMyFullName.text txtMyFirstName
  txtMyLastName
• What is result?
• NOTE ignore the discussion on pages 70-71 about
  default properties. In MINS114 you MUST be
  explicit in your naming

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Review

• What are the functions of TabIndex and TabStop?
  How do they work?
• What are three settings of the Font property?
• What are some issues with designing screens for
  users?
• How would you change the focus of the program to
  a command button named cmdStart?
• Given that you want the user to choose which
  class (freshman, sophomore, junior, senior) they
  are in, which type of Object would you use?
• What property would you use to set an option
  button as selected?