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Q189620: PRB: Form Scrollbar Property Read-Only at Run-Time

Article: Q189620
Product(s): Microsoft FoxPro
Version(s): WINDOWS:6.0
Operating System(s): 
Keyword(s): 
Last Modified: 11-DEC-1999

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The information in this article applies to:

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

The ScrollBar property of a form is read-only during run-time if the initial
value of the property is set to "0 - None". However, if you set the ScrollBar
property to any non-zero value, then the property can be changed during
run-time.

RESOLUTION
==========

To change the Scrollbar property during run-time, set the property to something
other than "0 - None" at design time and set the ScrollBar property to "0 -
None" in the Init event of the form. This causes the form to initially run
without scrollbars but with the ability to add scrollbars.

STATUS
======

This behavior is by design.

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

When the Scrollbar property is set to something other than "0 - None",
additional system resources are used to show the scrollbars. When the ScrollBar
property is set to "0 - None", these system resources are not reserved
unnecessarily.

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

1. The following code illustrates how to change the ScrollBar during run-time
  when the form initially runs with the ScrollBar property equal to "0 -
  None".

        frmScrollbar = CREATE("scrollbar")
        frmScrollbar.SHOW(1)
        *
        DEFINE CLASS SCROLLBAR AS FORM
            TOP = 13
            LEFT = 13
            HEIGHT = 176
            WIDTH = 352
            SCROLLBARS = 1 &&Any non-zero value
            DOCREATE = .T.
            CAPTION = "ScrollBar Example"
            NAME = "Form1"

            ADD OBJECT command1 AS COMMANDBUTTON WITH ;
                TOP = 72, ;
                LEFT = 180, ;
                HEIGHT = 27, ;
                WIDTH = 144, ;
                CAPTION = "Change Scrollbar Prop", ;
                NAME = "Command1"

            ADD OBJECT spinner1 AS SPINNER WITH ;
                HEIGHT = 24, ;
                LEFT = 70, ;
                SPINNERHIGHVALUE =   3.00, ;
                SPINNERLOWVALUE =   0.00, ;
                TOP = 72, ;
                WIDTH = 50, ;
                NAME = "Spinner1"

            ADD OBJECT label1 AS LABEL WITH ;
                HEIGHT = 48, ;
                LEFT = 70, ;
                TOP = 20, ;
                WIDTH = 250, ;
                WORDWRAP = .T., ;
                CAPTION = ;
                "Adjust the form size and then change the ;
                 ScrollBar property."

            PROCEDURE INIT
                THIS.SCROLLBARS = 0
            ENDPROC

            PROCEDURE command1.CLICK
                THISFORM.SCROLLBARS = THISFORM.spinner1.VALUE
            ENDPROC

        ENDDEFINE

        *-- Code ends here.

Additional query words: kbVFp600 kbOOP

======================================================================
Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP600
Version           : WINDOWS:6.0
Issue type        : kbprb

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