PageFrame Parameterized View Example

• Microsoft Visual FoxPro for Windows, versions 3.0, 5.0
• Microsoft Visual FoxPro for Macintosh, version 3.0b

SUMMARY

This article provides a complete example showing how to create a PageFrame that has Pages and ListBoxes to display the results of a parameterized view from a single table. The views created may be modified to suit a specific situation.

MORE INFORMATION

It is assumed that you are familiar with the View Designer.

1. Create the following Views in Vpf\Samples\Mainsamp\Data\Tastrade.dbc database:

   NOTE: When you create the local view in the View Designer, set the parameter in the SELECT statement to the List Value property, as in the following SELECT statements. For example in the View Designer for List2, place "city" in the Selected Output field, "country" in the Field Name field, and ?ThisForm.PageFrame1.Page1.List1.Value in the Example field.

   View List2:

         SELECT customer.city FROM tastrade!customer ;
            WHERE customer.country = ?ThisForm.PageFrame1.Page1.List1.Value
   
      View List3:
   
         SELECT customer.company_name FROM tastrade!customer ;
            WHERE customer.city = ?ThisForm.PageFrame1.Page2.List1.Value
   
      View List4:
   
         SELECT customer.customer_id FROM tastrade!customer WHERE ;
            customer.company_name = ?ThisForm.PageFrame1.Page3.List1.Value
   
   

2. On a Form, place a PageFrame with 4 Pages and a ListBox on each Page. Establish the following methods and properties for the Form and PageFrame Pages:

   a. In the Init event of the form:

         This.DataEnvironment.OpenTables
   

         This.PageFrame1.Page2.List1.RowSource='List2'
         This.PageFrame1.Page2.List1.RowSourceType=2
   

         This.PageFrame1.Page3.List1.RowSource='List3'
         This.PageFrame1.Page3.List1.RowSourceType=2
   

         This.PageFrame1.Page4.List1.RowSource='List4'
         This.PageFrame1.Page4.List1.RowSourceType=2
   

   b. On the Property Sheet for Page1.List1:

         Page1.List1.RowSource
   

            SELECT distinct Country from Customer into Cursor abc
   
         Page1.List1.RowSourceType
   
            3 - SQL Statement
   
      c. In the InterActiveChange event for Page 1.List1:
   
         *This is for the List on Page 1
   
         = REQUERY("List2")
   
         ThisForm.PageFrame1.Page2.List1.RowSource='List2'
         ThisForm.PageFrame1.Page2.List1.RowSourceType=2
         ThisForm.PageFrame1.Page2.List1.requery( )
   
      d. In the Page2.List1.LostFocus event:
   
         NOTE: The Help file recommends that the following code be placed in
         the InterActiveChange method but testing has shown that if there is
         only one selection available beyond Page1, the subsequent Lists are
         not updated.
   
         *This is for the ListBox on Page 2
         = REQUERY("List3")
   
         ThisForm.PageFrame1.Page3.List1.RowSource='List3'
         ThisForm.PageFrame1.Page3.List1.RowSourceType=2
         ThisForm.PageFrame1.Page3.List1.requery( )
   
      e. In the Page3.List1.LostFocus event:
   
         *This is for the ListBox on Page 3
   
         = REQUERY("List4")
   
         ThisForm.PageFrame1.Page4.List1.RowSource='List4'
         ThisForm.PageFrame1.Page4.List1.RowSourceType=2
         ThisForm.PageFrame1.Page4.List1.Requery( )
   
   

3. Create a DataEnvironment for the form.

   a. Include the following table and views from the TASTRADE.DBC:

         1. Customer table
         2. View List2
         3. View List 3
         4. View List 4
   

   b. Set the DataEnvironment.AutoOpenTables property to false (.F.).