53 Form: Ghost object created for table bound fields when a form is run

VERSIONS: Paradox 9 and later
SUBJECT: Ghost object created for table bound fields
BY: IVICA KOLAR
Note: This text was earlier found in DocIssues, Wadid 222

When creating a form based on a table, Paradox will during execution create temporary text objects for some (maybe all) of the tablebound fields. The text object has the same name for every container. During the tests, it was always named #Text28. Maybe it is one object being moved when tabbing between fields.

This behaviour is first verifed in Paradox 9 SP4. It does not happen in P7 SP4 and P8 SP1. It could be part of the new solution for required fields introduced by Corel in P9.

Object has been identified in forms with a tableFrame object or a Mro object. It has not been tested in a form with no record container.

When using enumUiobjectNames(), you should be aware of the existence of this object.

SETUP:

1. Create a new form. Put tableFrame on it. Bind tableFrame to a table
2. 2. Add the code below to action method at tableFrame level
3. 3. Save/Close/Run
4. 4. Move between tableFrame fields using keyboard
   Result:Unexpected ui encountered.

proc uGhostHunting(id smallint)
var
   ui UIObject
   stFullName, stContainer String
   arstObjects Array[] String
   liCounter Longint
   darstProperties DynArray[] string
endvar

;target field in current record
stFullName = active.FullName
stContainer = active.ContainerName
ui.attach( stContainer )
ui.enumObjectNames( arstObjects )
liCounter = arstObjects.indexOf( stFullName ) +1
if liCounter < arstObjects.size() then
   if ui.attach(arstObjects[ liCounter ]) then
      if ui.Class = "Text" then
         ;P10: Ghost Text ui is here
         ui.enumUIObjectProperties(darstProperties)
         darstProperties.view("Ghost attack! Id= "+string(id))
         ;BTW: Do you know that we can move to Text ui? 
         ; ui.moveTo() does that.
      endif
   endif
endif
endproc

method action(var eventInfo ActionEvent)
var
   siId SmallInt
endvar
siId  = eventInfo.id()
switch
   case siId  = FieldForward :
   case siId  = MoveRight :
   case siId  = FieldRight :
   case siId  = FieldBackward :
   case siId  = MoveLeft :
   case siId  = FieldLeft : 
   otherwise: 
      return
endswitch
uGhostHunting(siId)
endMethod
endMethod

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