PSLine2000Documentation/Forms/Universal Selection Screen.md

Universal Selection Screen

Analysis generated on: 4/1/2025 4:04:39 PM

Record Source

• None

Controls

Control Name	Reference
None	-

VBA Code

Option Compare Database   'Use database order for string comparisons

Private Sub Button2_Click()
   Call ckPrimaryScreen
   ErrM.Caption = ""
   Mater$ = UnivREQName$ + "=" + Chr$(34) + itsaNull$(Answer) + Chr$(34)

   If itsaNull$(Answer) <> "" Then
      DoCmd.OpenForm PrimaryScreen$, , , Mater$
   Else
      ErrM.Caption = "Invalid " + UnivREQName$ + " Selected"
   End If
End Sub

Private Sub Form_Open(Cancel As Integer)
   If Trim$(UnivREQName$) = "" Then
      UnivREQName$ = "PartNumber"
   End If
   Header.Caption = "Select " + UnivREQName$
   prompt.Caption = UnivREQName$ + ":"

End Sub

What it does

Code Description

Overview

This VBA code snippet is part of an Access database application. It defines two event handlers: Button2_Click and Form_Open.

Button2_Click Event Handler

The Button2_Click event handler is triggered when the button with identifier "Button2" is clicked.

Step-by-Step Explanation

1. Check Primary Screen: The code calls another subroutine, ckPrimaryScreen, which is not shown in this snippet. This suggests that it performs some preliminary checks or validation before proceeding.
2. Clear Error Message: An error message box (ErrM) is cleared by setting its caption to an empty string using the Caption property.
3. Construct Form Parameter: A parameter string (Mater$) is constructed by concatenating three values:
   • UnivREQName$: a field in the database containing the required university or school name.
   • itsaNull$(Answer): an expression that evaluates to a boolean value, likely indicating whether the answer is null. The result is wrapped in single quotes ('') and then enclosed in single quotes again (e.g., 'yes' or ''). This suggests that the database expects the value to be returned as a string.
4. Open Primary Screen Form: If the Answer field is not empty (itsaNull$(Answer) \u003c\u003e ""), the code opens a form with identifier "PrimaryScreen" using DoCmd.OpenForm. The Mater$ parameter is passed to this method, which likely uses it as part of the form's title or header.
5. Invalid Answer Handling: If the Answer field is empty (itsaNull$(Answer) = ""), an error message box with a custom caption ("Invalid " + UnivREQName$ + " Selected") is displayed.

Form_Open Event Handler

The Form_Open event handler is triggered when a form with identifier "Form" (or another identifying name, not shown in this snippet) is opened or loaded.

Step-by-Step Explanation

1. Default Value: If the UnivREQName$ field is empty (Trim$(UnivREQName$) = ""), it defaults to a value of "PartNumber".
2. Form Header and Prompt: The header caption of the form ("Header") is updated to reflect the current university or school name, which is stored in UnivREQName$. The prompt text (prompt`) is also updated to match the current university or school name.

In summary, this code snippet handles button click events and form opening events in an Access database application. It performs validation checks, constructs parameter strings for form operations, and updates form headers and prompts based on user input values.