Q191316: PRB: SET DATASESSION TO Fails From a Method of _Screen

Article: Q191316
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0,5.0a,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, versions 5.0, 5.0a, 6.0 
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SYMPTOMS
========

Attempting to set the data session of a form by calling the SET DATASESSION TO
command from a method of _SCREEN fails.

STATUS
======

This behavior is by design.

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

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

1. Create a program that contains the following code:

        CLEAR ALL
        PUBLIC yy,Y,zz

        * The target session we are trying to SET TO:
        Y = CREATEOBJECT("zform")

        * A separate custom object, which can set to that session:
        zz = CREATEOBJECT("myobj")

        * A form in another session, which can set to that session:
        yy = CREATEOBJECT("zform2")

        * A member of screen, which will show the problem:
        _SCREEN.ADDOBJECT("z","myobj")

        Y.SHOW()
        yy.SHOW()

        RETURN

        DEFINE CLASS myobj AS CUSTOM

           PROCEDURE SetToActiveSession
              WAIT WINDOW TIMEOUT 1 ;
              "current ;
              session: "+STR(SET("datasession"))
              SET DATASESSION TO ;
              (_SCREEN.ACTIVEFORM.DATASESSIONID)
              WAIT WINDOW "session we want: "+;
              ALLTR(STR(_SCREEN.ACTIVEFORM.DATASESSIONID))+ ;
              ", "+ CHR(13)+ ;
              "session we got: "+ ;
              ALLTR(STR(SET("DATASESSION"))) TIMEOUT 3
           ENDPROC

        ENDDEFINE

        DEFINE CLASS zform AS FORM
           DATASESSION = 2
        ENDDEFINE

        DEFINE CLASS zform2 AS zform
           AUTOCENTER = .T.
           ADD OBJECT z AS COMMANDBUTTON WITH ;
           CAPTION="Push Me"
           PROCEDURE  z.CLICK
           WAIT WINDOW TIMEOUT 1 "current session: "+STR(SET("datasession"))
           SET DATASESSION TO (Y.DATASESSIONID)
           WAIT WINDOW "session we want: "+ ;
           ALLTR(STR(Y.DATASESSIONID))+ ;
           ", "+CHR(13)+ ;
           "session we got: "+ ;
           ALLTR(STR(SET("DATASESSION"))) TIMEOUT 1
           ENDPROC
        ENDDEFINE

2. Run the program and press the command button. Notice the data session starts
  out with a value of three (3) and changes to a value of two (2).

3. Change the data session from the Command window by typing the following
  command:

  " zz.SetToActiveSession()" (without the quotation marks)

  Notice the data session starts with a value of one (1) and successfully
  changes to two (2).

4. Attempt to change the data session from the Command window using a method of
  the _SCREEN object by typing the following:

  " _Screen.z.SetToActiveSession()" (without the quotation marks)

  Calling the _SCREEN object does not allow you to change the data session to a
  value of two (2). It remains a value of one (1).

Additional query words: kbVFp500a kbVFp600 kbOOP

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP600 kbVFP500a
Version           : WINDOWS:5.0,5.0a,6.0
Issue type        : kbprb

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