VIFRED Exercise

Objectives:

1. To explore the range of facilities provided by the Ingres Visual FoRms Editor(VIFRED).
2. To amend existing default Forms to provide a better User Interface.
3. To explore the data validation facilities provided by VIFRED to ensure that only 'good' data is entered onto the database.
4. To learn how VIFRED allows Forms to control NULL values at the application level.

From the top level Inges/Menu, invoke the Forms utility

Creating Forms

• borrower (table, use simplefields),
• author (table, tablefields),
• borrower_loans (joindef created in joindef exercise),
• borrower_reservations (view created in views exercise).

1. Invoke the Create function.
2. From the VIFRED - Creating a Form window, Select f(8) the Table option.
3. In the VIFRED - Creating a Form Based on a Table window, add the tablename borrower and select the simplefields Display Format option. OK f(8) your entry.
4. This has created a basic form. We will come back to editting it on the next step. For now:
   1. Save your form, selecting Save(f5) twice.
   2. End(f3).
5. Repeat the above steps, using tablefields where appropriate to create all the required forms:
   • for the Author table, create form based on a table using tablefields layout,
   • for the borrower_loans joindef, create form based on a joindef,
   • for the borrower_reservations view, create form based on a table using tablefields layout.

Altering the Screen Design

1. In the VIFRED - Forms Catalog, Edit the form for author, created above.
2. Centre the AUTHOR TABLE: text.
   1. Invoke the Edit option, editting trim.
   2. Type spaces over the current AUTHOR TABLE: text and retype it, using mixed case, over the top of the table.
      Hints:

      • the 'Insert Char' key on the keyboard toggles between insert and overtype modes.
      • the <MENU KEY> is f1.
3. Rename the column headings.
   1. Press the tab key, this move the cursor between the page heading and the actual table, press it a couple of times, watching the cursor move back and forth between the two points.
   2. With the cursor on the top left corner of the table, invoke the Edit option, this will open the VIFRED - Table Field screen.
   3. Change the Title of a Column field to read Book Number for isbnx (Column Internal Name) and Authors Name for author_name (Column Internal Name).
4. (Still in the VIFRED - Table Field screen) Reorder the columns.
   1. Highlight the Authors Name row.
   2. Invoke the Move option.
   3. Move the current row highlight to the top of the table and invoke the Place option.
   4. End(f3) to get back to the main form.
5. Save your form, selecting Save(f5) twice.
6. Repeat similar operations for the other forms you have created.
   For borrower_loans, do the following:

   1. Delete the Bor State, Addr1, Addr2, Town & Post Code fields.
   2. Replace the BOOK, LOAN, COPIES TABLES: text with Books on Loan.
   3. Delete some of the blank lines between the borrower and books information.
   4. Alter the table field to:
      1. Number of Rows to Display: 12
      2. Display only the following columns, with the following titles, in the following order:
         • access_no, titled Number.
         • title, titled Title
         • loan_date, titled Loan Date
         • use the EditAttr option to set the Invisible flag to 'y' for:
           • Isbnx
           • Buy Price
           • Buy Date
           • Pub Code
           • Pub Date
           • Now Price
      Note how the tab key moves you around the various parts of a form when you are editing the form based on the borrower_loans joindef.

      End(f3) the edit attributes screen and use Save(f5) to save the change you have made.

      Now back out of the forms creation utility and invoke the Go(f8) option to run the borrower_loans form and examine how it works.