outline

Modules

• Description of a module:
     - they are like separate files on a disk
     - they are like the code part of a form - no objects are attached
     - are saved on the disk with a .BAS extension

What do they contain?

• Modules contain record definitions
• GLOBAL variable declarations
• Global procedures

How are they used?

• Modules are used to declare GLOBAL variables
     - use the keyword GLOBAL in place of DIM
     - can only be used in the general area of a module
     - otherwise used just like DIM

Creation of global procedures

• Because they are global, they can be called from any form, any procedure in the project
• It is just like creating a new command
• Can be used to store a library of useful subprograms (e.g., printing related)
• Are created by choosing New Module from the File menu or hitting New Module button

Scope map

Global procedures

• Are created in the general area of forms or modules
• In forms, makes a form-level procedure
• In modules, makes a global procedure
• Can be called from within code - New command

Syntax

• Sub ProcedureName (Parameters)
• Creates a new section of the general area
• Code can be written in this area

Parameters

• "Instant" local variable(s)
• They don't have to be declared
• To call a procedure -simply use its name in code

Multiple forms

• To create use New Form on the File menu or New Form button
• Useful methods -
     -Show
     - Hide

Show

• Syntax: FormName.Show 1
• This action is modal
• The FormName is the name of the form you have created in the project

Example

• Second.Show 1
• This loads Second into memory if it's not there and shows it to the user

Modal switch

• If you end the show method with a 1, the form will be modal
• The new form gets focus
• The next code that is activated is in the form_load procedure of the second form
• The control reverts to the original form after the second is closed
• If you do not put a 1 at the end, the form shows up, but does not get the focus
• The control of the program moves on to the next line of code in the first form

Hide

• Syntax: FormName.Hide
• Example: Second.Hide
• This hides the named form and the control reverts back to the procedure that showed the form
• Warning! Don't hide ALL the forms in a project!

Startup form

• One form must be designated as the startup form
• By default this will be the first form created
• To change this, use the Project dialog under the Options Menu