Q248226: BUG: ListIndex Value Not Updated Correctly In Loop with AddItem

Article: Q248226
Product(s): Microsoft FoxPro
Version(s): WINDOWS:6.0
Operating System(s): 
Keyword(s): kbContainer kbCtrl kbvfp600 kbvfp600bug kbGrpDSFox kbDSupport kbCodeSnippet
Last Modified: 30-DEC-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 6.0 
-------------------------------------------------------------------------------

SYMPTOMS
========

Adding items in a list box using the AddItem method and including the ListIndex
property in a loop gives unordered entries in the list box.

CAUSE
=====

The problem is due to the fact that the value of ListIndex, which is being used
to increment ListIndex property, does not return the correct value.

RESOLUTION
==========

Use a memory variable to store the incrementing value instead of the ListIndex
property.

Replace the Click event of the Command1 with the following:

  PROCEDURE command1.Click
  	local lnI, nCn
  	with thisform
  		nCn=.list1.ListIndex
  		FOR lnI = 1 TO 50
  			.list1.AddItem(" "+STR(lnCounter), nCn+1, 1)
  			nCn = nCn + 1
  			lnCounter = lnCounter + 1
  			.list1.ListIndex=ncn
  		NEXT
  	Endwith
  ENDPROC 

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article.

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

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

1. Create a program and include the following code in it. Save and run the
  program.

  ******* Start of the Code
  PUBLIC oform1

  	oform1=NEWOBJECT("form1")
  	oform1.Show

  RETURN

  DEFINE CLASS form1 AS form
  	Top = 0
  	Left = 0
  	Height = 452
  	Width = 633
  	DoCreate = .T.
  	Caption = "Form1"
  	WindowState = 2
  	Name = "Form1"

  	ADD OBJECT command1 AS commandbutton WITH ;
  		Top = 180, ;
  		Left = 144, ;
  		Height = 48, ;
  		Width = 216, ;
  		FontBold = .T., ;
  		FontSize = 15, ;
  		Caption = "Add Item", ;
  		Name = "Command1"

  	ADD OBJECT list1 AS listbox WITH ;
  		ColumnCount = 1, ;
  		ColumnWidths = "60", ;
  		RowSourceType = 1, ;
  		Height = 120, ;
  		Left = 144, ;
  		Top = 24, ;
  		Width = 204, ;
  		Name = "List1"

  	ADD OBJECT command2 AS commandbutton WITH ;
  		Top = 240, ;
  		Left = 144, ;
  		Height = 48, ;
  		Width = 216, ;
  		FontBold = .T., ;
  		FontSize = 15, ;
  		Caption = "Quit", ;
  		Name = "Command2"

  	PROCEDURE Load
  		PUBLIC lnCounter
  		lnCounter = 0
  	ENDPROC

  	PROCEDURE command1.Click
  		local lnI
  		with thisform
  			FOR lnI = 1 TO 50
  				.list1.AddItem(" "+STR(lnCounter), .list1.ListiNDEX+1, 1)
  				.list1.ListIndex = .list1.ListIndex + 1
  				lnCounter = lnCounter + 1
  			NEXT
  		Endwith
  	ENDPROC

  	PROCEDURE command2.Click
  		thisform.release
  	ENDPROC

  ENDDEFINE

  ******* End of the Code

2. Click the command button Add Item.

3. Notice the contents of the list box are not ordered correctly.

Additional query words: KBDSE

======================================================================
Keywords          : kbContainer kbCtrl kbvfp600 kbvfp600bug kbGrpDSFox kbDSupport kbCodeSnippet 
Technology        : kbVFPsearch kbAudDeveloper kbVFP600
Version           : WINDOWS:6.0
Issue type        : kbbug
Solution Type     : kbpending

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