DOCUMENT:Q249633  05-JAN-2000  [foxpro]
TITLE   :Setting a Filter Allows no Real Time Scrolling in Listbox
PRODUCT :Microsoft FoxPro
PROD/VER:WINDOWS:5.0,5.0a,6.0
OPER/SYS:
KEYWORDS:kbContainer kbCtrl kbvfp500 kbvfp500a kbvfp600 kbGrpDSFox kbDSupport kbCodeSnippet

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The information in this article applies to:

 - Microsoft Visual FoxPro for Windows, versions 5.0, 5.0a, 6.0 
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SYMPTOMS
========

When using the scroll button of a combo or list box to scroll through data that
has a SET FILTER TO expression, the data in the combo or list box will not be
refreshed to show the new data until the mouse button is released. If there is
no SET FILTER used on the data the data moves as the scroll button moves and
immediately displays the new data.

NOTE: Setting DELETED ON in Visual FoxPro 6.0 causes the same behavior to occur.

STATUS
======

This behavior is by design. When any type of filter is used there is no real
time scrolling of data in a combo or list box.

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

1. Copy the following code into a program (.prg) file and then run the program.
   This code uses the customer.dbf sample table that comes with Visual FoxPro.
   Make sure that a path is set to the table:

      PUBLIC oform
           oform = CREATEOBJECT("frmFilterTest")
           oform.Show
       
           DEFINE CLASS frmFilterTest AS form
                 Top = 0
                 Left = 0
                 Height = 255
                 Width = 354
                 DoCreate = .T.
                 Caption = "frmFilterTest"
                 Name = "frmFilterTest"

                 ADD OBJECT cboFilter AS combobox WITH ;
                           RowSourceType = 6, ;
                           RowSource = "customer.cust_id", ;
                           Height = 24, ;
                           Left = 24, ;
                           Top = 36, ;
                           Width = 100, ;
                           Name = "cboFilter"

                 ADD OBJECT lstCustomer AS listbox WITH ;
                           RowSourceType = 6, ;
                           RowSource = "customer.cust_id", ;
                           Height = 170, ;
                           Left = 180, ;
                           Top = 24, ;
                           Width = 100, ;
                           Name = "lstCustomer"

                 ADD OBJECT cmdFilter AS commandbutton WITH ;
                           Top = 156, ;
                           Left = 24, ;
                           Height = 27, ;
                           Width = 84, ;
                           Caption = "Filter On", ;
                           Name = "cmdFilter"

                 PROCEDURE Load
                           SET DELETED OFF
                           SET FILTER to maxordamt > 1000

                 PROCEDURE cmdFilter.Click
                           IF This.caption='Filter On'
                                   SET FILTER TO
                                   This.caption='Filter Off'
                           ELSE
                                   SET FILTER TO maxordamt > 1000
                                   This.caption='Filter On'
                           ENDIF

2. Move the scroll button of the list or combo box and note that the data does
   not refresh until the mouse button is released.

3. Select the Set Filter command button to turn the filter off and note that the
   data moves interactively when the scroll button is moved.

4. Changing the SET DELETED OFF command to ON in the Load event of the code
   causes the same behavior to occur in both the combo and list boxes when you
   use Visual FoxPro 6.0.

Additional query words: KBDSE

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Keywords          : kbContainer kbCtrl kbvfp500 kbvfp500a kbvfp600 kbGrpDSFox kbDSupport kbCodeSnippet 
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP600 kbVFP500a
Version           : WINDOWS:5.0,5.0a,6.0
Issue type        : kbprb

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