BUG: SHOW GET Does Not Refresh Number of Elements

ID: Q134638

The information in this article applies to:

Microsoft Visual FoxPro for Windows, versions 3.0, 3.0b, 5.0, 5.0a, 6.0

SYMPTOMS

A screen converted from a previous version of FoxPro to a Visual FoxPro form doesn't display added items when both of the following conditions are met:

The original screen has a list box that is populated from an array.
The original screen has an event procedure (such as a command button click procedure) that adds items to the array, and then refreshes the contents of the list with a SHOW GETS command.

CAUSE

The converter defines the list box with a "number of elements" property. That definition is exercised in the LOAD event of the form or formset. Visual FoxPro's converter does not insert the appropriate command to refresh the list box's "number of elements" property when the array size changes.

WORKAROUND

The VALID code of the converted command button adds an element to the array, and executes a SHOW GETS command. Immediately before the SHOW GETS command, insert a command to update the number of elements as in this example:

   ThisForm.Pageframe1.Page1.<listbox>.NumberOfElements=ALEN(<arrayname>)

STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Steps to Reproduce Problem

In FoxPro version 2.6a for Windows, create a screen that has a list box and two command buttons, as follows, using the Screen Builder:

1. On the File menu, click New. Then select the Screen option, and click

   the New button.

2. On the Screen menu of the Screen Builder, click Layout. Enter the name

   as Addu for the screen in the lower-left area of the dialog box.

   In the lower-right area, click Code. Then click Screen Setup Code, and
   then click OK twice to expose the edit window for the Setup code. In
   the setup code, enter the following three lines, and save the code by
   pressing CTRL+W:

      DIMENSION users(2)
      users(1)="One"
      users(2)="Two"

3. On the Screen Design toolbar, select the Command (push) button tool, and

   place a button on the screen design surface. In the Push Button dialog
   box, enter the prompt "\<Move=>" (without the quotation marks). In the
   bottom-left area, enter the variable name as m.mover.

4. Click the VALID button. In the Code Snippet dialog box, choose the

   Procedure option button, enter the following procedure in the edit area,
   and click OK twice to return to the Screen Builder:

      DIMENSION users(3)
      users(3)="Three"
      SHOW GET m.user

5. Select the List tool, and place a list box on the screen. In the List

   dialog box, select the List Items From Array option, and enter the word
   "Users" (without the quotation marks) in the edit box to the right. In
   the lower-left area, enter the name of the variable as m.user. In the
   edit region to the right of the First Element button enter the numeral
   1. For the # of Elements, enter ALEN(Users). Click OK to return to the
   Screen Builder.

6. Place another command button on the screen. In its push button dialog

   box, enter a prompt value of "\!\<OK " (without the quotation marks) and
   a variable name value of xyz. Click the Terminate Read on Selection
   check box. Click OK to return to the Screen Builder.

7. On the File menu, click Save As, and save the file as Addu.scx.

8. On the Program menu, click Generate to build a source code program

   named Addu.spr.

9. In the Command window, enter the following command to run the program:

      DO ADDU.SPR

10. Click the Move=> button, and observe the addition of the word "Three"

    to the list of words in the list box. Click OK to terminate the
    program.

Close FoxPro for Windows, start Visual FoxPro for Windows, and follow these steps:

1. In the Command window, enter the following commands, modifying them to

   reflect the appropriate path information:

   COPY FILE C:\FPW26\Addu.scx to Addu.scx
   COPY FILE C:\FPW26\Addu.scx to Addu.sct
   MODIFY FORM Addu.scx

2. In the Converter dialog box, click the Continue button to do a

   Functional Conversion.

3. Enter the following command in the command window to run the new form:

      DO FORM addu

   NOTE: The cleanup and procedures of an earlier screen are placed in a
   file with the same name as the form, with the extension .SPR.

4. Click the Move=> button, and observe that the word "Three" does not

   appear in the list box. Click OK to terminate the program.

5. Enter the following command in the command window:

      MODIFY FORM Addu.scx

6. Click the body of the form. Then click the right mouse button and

   select Edit from the context menu.

7. Click the Move button to select it, then click the right mouse button

   and select Properties from the context menu.

8. In the Property sheet for the command button, locate the Valid method

   entry, double-click it to open the edit window for that method. Enter
   the following command just above the SHOW GET m.user command:

      ThisForm.Pageframe1.Page1.lstUser2.NumberOfElements = ALEN(Users)

   Save the code by pressing CTRL+W. Then on the File menu, click Close,
   and answer Yes to Save changes.

9. Enter the following command in the Command window "do form addu," and

   then click the Move=> button to see the word "Three" now appears in the
   list.

Additional query words: kbvfp300 kbvfp500 kbvfp600

Keywords          : kbVFp kbVFp300bbug kbVFp500abug kbVFp500bug buglist3.00 FxotherGeneral kbbuglist
Version           : WINDOWS: 3.0,3.0b,5.0,5.0a,6.0
Platform          : WINDOWS
Issue type        : kbbug