Chapter 6' Multiple Forms

1
Chapter 6. Multiple Forms

• Form is window
• Startup form is the first form to be executed
• The form created in the first time
• From the Sub Main
• In the Project Properties
• Creating New Form
• Add Form from the Project menu
• Add Form button on the toolbar

2

• Adding the existing forms
• From the Project menu
• Click the Existing tab and Open the file
• Deleting the existing forms
• Choose Remove File form the Project menu
• Right-click on the filename and choose Remove
  Filename
• The Show Method
• FormName.Show Style
• frmSummary.Show 1 modal style
• frmSummary.Show vbModal
• frmSummary.Show vbModeless
• frmSummary.Show modeless style

3

• The Hide Method
• FormName.Hide
• frmSummary.Hide
• The Load Statement
• Load FormName
• Load frmSummary
• The Unload Statement
• Unload FormName
• Unload frmSummary
• Show and Load
• Show method loads and displays the form
• Load method only loads but doesnt display

4

• Hide and Unload
• Hide method hides the form from the screen, but
  the form still resides on the memory
• Unload method unloads the form from the memory
• The Me Keyword
• Unload Me Unload the form that is currently
  executing code
• Me.Hide
• Referring to Objects on a Different Form
• FormName.ObjectName.Property
• frmSummary.lblTotalAmount.Caption mcurTotal
• frmSummary.Show vbModal

5
Standard Code Modules

• To use the procedure in multiple forms
• .bas
• Add Module command on the Project menu
• Same as Form module
• Any Dimmed variables or constants in the General
  Declarations section of a standard code module
  are visible to all the procedures in that module,
  but not to the procedures in the form module(s).

6
Variables and Constants in Multiple-Form Projects

• Scope of variables and constants
• Local level
• Global level
• Module level
• Static (procedure level)
• Retain the value for the life of the project
• Static Identifier As DataType
• Static intPersonCount As Integer

7

• Guidelines for Declaring Variables and Constants
• Place all local declarations at the top of a
  procedure
• Use named constants for any value that doesnt
  change during program execution
• Keep the scope of variables and constants as
  narrow as possible
• Consider making variables and constants local if
  possible
• If you need to keep the value of a variable for
  multiple executions of a procedure, but dont
  need the variable in any other procedure, make it
  Static
• If you need to use a variable both in a procedure
  and also in a second procedure called by the
  first procedure, declare the variable as local
  and pass it as an argument
• If you need to use a variable in multiple
  procedures, such as to add to the variable in one
  procedure and to display it in another, use
  module-level variable
• Finally, if you really need the value of a
  variable in more than one form, make it global.
  Keep your Public declarations in a standard code
  module.

8
An About Box

• Help/About
• The name and version of the project
• Information about the programmer or company
• Create your own About box by creating a new form
• Use VBs About Dialog template to create a new
  About box
• Figure 6.7, Figure 6.8, and Figure 6.9

9
A Splash Screen

• A screen displayed while a program is loading
• Create your own Splash screen by creating a new
  Splash screen form
• Use VBs Splash screen template to create a new
  Splash screen form
• It can make a large application appear to load
  and run faster, since something appears on the
  screen while the rest of the application loads
• Figure 6.10 and Figure 6.11

10
Creating of Startup Form

• Coding the Standard Code Module
• Sub Main()
• frmSplash.Show vbModeless
• Load frmMain
• End Sub
• Coding the Splash Screen Event Procedure
• Private Sub cmdClose_Click()
• Unload Me
• frmMain.Show vbModal
• End Sub
• Setting the Startup Form or Procedure
• The default is the first form created in a
  project
• Choose one of the projects forms or Sub Main
  from the project properties