Q200296: BUG: ComboBox Display Bleeds Through Pages in a PageFrame

Article: Q200296
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0,5.0a,6.0
Operating System(s): 
Keyword(s): kbContainer kbCtrl kbvfp500 kbvfp500aBUG kbvfp600 kbvfp600bug kbGrpDSFox kbDSupport kbC
Last Modified: 07-JUL-2000

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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 you place a combo box control, which uses the InteractiveChange event to
programmatically activate the first page of the pageframe, on the second page of
a pageframe, when you select an item in that combo box the combo box display
image bleeds through to the first page.

RESOLUTION
==========

Here are two possible workarounds for this problem:

- Use a Timer control to activate the first page.

- Place code in the When event of the combo box to set its Visible property to
  false if the ActivePage of the pageframe is not the second page.

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. Place the following code into a Visual FoxPro program, and then run the
  program:

  DIMENSION laComboVals[2]
  laComboVals[1] = "Choice1"
  laComboVals[2] = "Choice2"

  oForm = CREATEOBJECT('TestForm')
  oForm.VISIBLE = .T.
  READ EVENTS

  **************************************
  DEFINE CLASS TestForm AS FORM
    ADD OBJECT pgfTest AS TestPageFrame

    PROCEDURE DESTROY
      CLEAR EVENTS
    ENDPROC
  ENDDEFINE

  DEFINE CLASS TestPageFrame AS PAGEFRAME
    TOP = 0
    LEFT = 0

    ADD OBJECT Page1 AS TestPage1
    ADD OBJECT Page2 AS TestPage2
  ENDDEFINE

  DEFINE CLASS TestPage1 AS PAGE
    ADD OBJECT Text1 AS TEXTBOX
  ENDDEFINE

  DEFINE CLASS TestPage2 AS PAGE
    ADD OBJECT cboTest1 AS TestCombo1 WITH ;
      TOP = 10
    ADD OBJECT cboTest2 AS TestCombo2 WITH ;
      TOP = 40
    ADD OBJECT cboTest3 AS TestCombo3 WITH ;
      TOP = 70
    ADD OBJECT Timer1 AS Timer1
      
    PROCEDURE CLICK
      THIS.cboTest2.VISIBLE = .T.
    ENDPROC
  ENDDEFINE

  DEFINE CLASS TestCombo1 AS COMBOBOX
    LEFT = 5
    ROWSOURCETYPE = 5
    ROWSOURCE = "laComboVals"

    PROCEDURE INTERACTIVECHANGE
      THIS.PARENT.PARENT.ACTIVEPAGE=1
      THIS.PARENT.PARENT.Page1.Text1.SETFOCUS()
      THISFORM.REFRESH()
    ENDPROC
  ENDDEFINE

  DEFINE CLASS TestCombo2 AS COMBOBOX
    LEFT = 5
    ROWSOURCETYPE = 5
    ROWSOURCE = "laComboVals"
    
    PROCEDURE INTERACTIVECHANGE
      THIS.PARENT.PARENT.ACTIVEPAGE=1
      THIS.PARENT.PARENT.Page1.Text1.SETFOCUS()
      THISFORM.REFRESH()
    ENDPROC
    
    PROCEDURE WHEN
      IF This.Parent.Parent.ACTIVEPAGE <> 2
        THIS.VISIBLE = .F.
      ENDIF
    ENDPROC
  ENDDEFINE

  DEFINE CLASS TestCombo3 AS COMBOBOX
    LEFT = 5
    ROWSOURCETYPE = 5
    ROWSOURCE = "laComboVals"

    PROCEDURE INTERACTIVECHANGE
      THIS.PARENT.Timer1.ENABLED = .T.
    ENDPROC
  ENDDEFINE

  DEFINE CLASS Timer1 AS TIMER
    INTERVAL = 10

    PROCEDURE TIMER
      THIS.PARENT.PARENT.ACTIVEPAGE=1
      THIS.PARENT.PARENT.Page1.Text1.SETFOCUS()
      THISFORM.REFRESH
      THIS.ENABLED = .F.
    ENDPROC
  ENDDEFINE

2. Select an item from each of the combo boxes on page two. The results are:

   - The first (topmost) combo box bleeds through to the first page.

   - The second combo box uses the When event solution so it does not bleed
     through to the first page.

   - The third combo box uses the Timer solution so it also does not bleed
     through to the first page.

Additional query words:

======================================================================
Keywords          : kbContainer kbCtrl kbvfp500 kbvfp500aBUG kbvfp600 kbvfp600bug kbGrpDSFox kbDSupport kbCodeSnippet 
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP600 kbVFP500a
Version           : WINDOWS:5.0,5.0a,6.0
Issue type        : kbbug
Solution Type     : kbnofix

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