Alô Lassala,

O problema ocorre em tempo de execução também.
Este código ( ThisForm.l1.Left = ThisForm.T.value ) está num CommandButton.
Estou mandando o código pra vc ver. Veja a confusão de chamadas que o
programa faz.

Até+
Marcus Rio Apa
**************************************************
*-- Class: list_teste (c:\a\a.vcx)
*-- ParentClass: listbox
*-- BaseClass: listbox
*-- Time Stamp: 01/31/02 03:22:12 PM
*
DEFINE CLASS list_teste AS listbox

Height = 170
Width = 100
Name = "l"


PROTECTED PROCEDURE this_access
Lparameters cMemberName
MessageBox("Método Access")
DO case
Case cMemberName = 'caption'
MessageBox("Acessou a propriedade caption")
Case cMemberName = 'listcount'
MessageBox("Acessou a propriedade ListCount")
Case cMemberName = 'left'
MessageBox("Acessou a propriedade Left")
Case cMemberName = 'width'
MessageBox("Acessou a propriedade Width")
OtherWise
MessageBox(Str(cMemberName))
EndCase
Return This
ENDPROC


PROCEDURE left_assign
LPARAMETERS vNewVal
MessageBox("Método Assign")
If vNewVal > 30
MessageBox("Maior que 30. Altera")
THIS.LEFT = m.vNewVal
Else
MessageBox("Menor que 30. Não altera")
return
EndIf
ENDPROC


ENDDEFINE
*
*-- EndDefine: list_teste
**************************************************

E agora, o código do form:
**************************************************
PUBLIC oform1

SET CLASSLIB TO c:\a\a.vcx ADDITIVE

oform1=NEWOBJECT("form1")
oform1.Show
RETURN


**************************************************
*-- Form: form1 (c:\a\form2.scx)
*-- ParentClass: form
*-- BaseClass: form
*-- Time Stamp: 01/31/02 03:24:03 PM
*
DEFINE CLASS form1 AS form


Top = 14
Left = 53
Height = 139
Width = 290
DoCreate = .T.
Caption = "Form1"
Name = "FORM1"


ADD OBJECT command1 AS commandbutton WITH ;
Top = 48, ;
Left = 144, ;
Height = 27, ;
Width = 84, ;
Caption = "Assign", ;
TabIndex = 1, ;
Name = "Command1"


ADD OBJECT t AS textbox WITH ;
Alignment = 3, ;
Value = 10, ;
Height = 23, ;
Left = 144, ;
TabIndex = 3, ;
Top = 12, ;
Width = 100, ;
Name = "t"


ADD OBJECT command2 AS commandbutton WITH ;
Top = 84, ;
Left = 144, ;
Height = 27, ;
Width = 84, ;
Caption = "Access", ;
TabIndex = 2, ;
Name = "Command2"


ADD OBJECT l1 AS list_teste WITH ;
Height = 100, ;
Left = 36, ;
Top = 12, ;
Width = 96, ;
Name = "l1"


PROCEDURE this_access
LPARAMETER cMemberName && Object member name
IF cMemberName = 'caption'
? cMemberName && Display the object member name
ENDIF
RETURN THIS
ENDPROC


PROCEDURE this_assign
LPARAMETERS vNewVal
*To do: Modify this routine for the Assign method
THIS.This = m.vNewVal
ENDPROC


PROCEDURE width_access
*To do: Modify this routine for the Access method
Lparameters a
MessageBox("Acessou o Width",0,"Clientes IV")
If a > 500
MessageBox("> 500",0)
Return
Else
MessageBox("< 500",0)
RETURN THIS.WIDTH
EndIf
ENDPROC


PROCEDURE command1.Click
ThisForm.l1.Left = ThisForm.T.value
ENDPROC


PROCEDURE command2.Click
MessageBox(Str(Thisform.l1.Left))

ENDPROC


ENDDEFINE
*
*-- EndDefine: form1
**************************************************