Q190567: BUG: GotFocus() Sets Commandbutton Default to Initial Setting
Article: Q190567
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0,5.0a
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
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SYMPTOMS
========
If you create a form which programmatically sets a command button Default
property to .T., when you navigate through controls on your form, the Default
status of any of the command buttons on your forms reverts to the initial
setting. For example, if your form had no default command button, there will be
no default command button. If your form had a different default command button,
that button will once again become the default.
CAUSE
=====
The intrinsic Visual FoxPro Gotfocus() event behavior resets the command button
default properties to their initial values.
RESOLUTION
==========
See the MORE INFORMATION section below for a possible workaround.
STATUS
======
Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This problem has been corrected in Visual FoxPro 6.0.
MORE INFORMATION
================
A command button with a Default property set to .T., appears with a darkened
border. It also responds as if clicked when you press the ENTER key when focus
is on another control, such as a text box.
Steps to Reproduce Behavior
---------------------------
1. Run the following code from a program (.prg) file:
PUBLIC oForm1
oForm1=CREATEOBJECT("form1")
oForm1.Show
DEFINE CLASS Form1 AS form
AutoCenter = .T.
Height = 252
Width = 326
Name = "Form1"
ADD OBJECT Text1 AS textbox WITH ;
Height = 23, ;
Left = 36, ;
Top = 24, ;
Width = 100, ;
Name = "Text1"
ADD OBJECT Command1 AS commandbutton WITH ;
Top = 24, ;
Left = 204, ;
Height = 27, ;
Width = 84, ;
TabStop = .F., ;
Name = "Command1", ;
Default = .T.
ADD OBJECT Command2 AS commandbutton WITH ;
Top = 72, ;
Left = 204, ;
Height = 27, ;
Width = 84, ;
TabStop = .F., ;
Name = "Command2"
ADD OBJECT Edit1 AS editbox WITH ;
Height = 49, ;
Left = 48, ;
Top = 192, ;
Width = 216, ;
Name = "Edit1"
PROCEDURE Text1.LostFocus
ThisForm.Command1.default = .T.
ENDPROC
PROCEDURE Edit1.LostFocus
ThisForm.Command2.default = .T.
ENDPROC
ENDDEFINE
2. Tab through the text box and edit box.
Command1 remains the default command button. The property is actually set, but a
reset to the original default occurs in the intrinsic GotFocus behavior for all
Visual FoxPro controls.
This following program demonstrates this behavior. You issue a GotFocus() in the
GotFocus() event for the text box and edit box, to cause the intrinsic behavior
to occur, then you set the default button. In this case, the default button
actually changes.
Sample Code
-----------
PUBLIC oForm1
oForm1=CREATEOBJECT("form1")
oForm1.Show
DEFINE CLASS Form1 AS form
AutoCenter = .T.
Height = 252
Width = 326
Name = "Form1"
ADD OBJECT Text1 AS textbox WITH ;
Height = 23, ;
Left = 36, ;
Top = 24, ;
Width = 100, ;
Name = "Text1"
ADD OBJECT Command1 AS commandbutton WITH ;
Top = 24, ;
Left = 204, ;
Height = 27, ;
Width = 84, ;
TabStop = .F., ;
Name = "Command1", ;
Default = .T.
ADD OBJECT Command2 AS commandbutton WITH ;
Top = 72, ;
Left = 204, ;
Height = 27, ;
Width = 84, ;
TabStop = .F., ;
Name = "Command2"
ADD OBJECT Edit1 AS editbox WITH ;
Height = 49, ;
Left = 48, ;
Top = 192, ;
Width = 216, ;
Name = "Edit1"
PROCEDURE text1.GotFocus
DoDefault()
ThisForm.Command1.default = .T.
ENDPROC
PROCEDURE edit1.GotFocus
DoDefault()
ThisForm.Command2.default = .T.
ENDPROC
ENDDEFINE
A potential workaround, which is likely to be difficult to implement, would be to
use code like the preceding code to manage your default command buttons. Keep in
mind that the intrinsic GotFocus behavior does the reset, so the GotFocus()
event for all controls, even those which do not set a command button to default,
causes the reset to occur. A workaround would involve adding code to all
control's GotFocus() method to find and store the current default button, issue
a DoDefault(), and restore the correct default button. However, the DoDefault()
function only works in Visual FoxPro 5.0 and later versions.
Code similar to the following could be added to the GotFocus() method for all
controls on a form for a workaround:
Sample Code
-----------
LOCAL loDefaultButton, lni
WITH thisform
FOR lni = 1 to .Controlcount
IF .Controls(lni).Baseclass = 'Commandbutton' ;
and .Controls(lni).Default = .t.
loDefaultButton = .Controls(lni)
ENDIF
ENDFOR
ENDWITH
DoDefault()
IF type('loDefaultButton') = "O"
loDefaultButton.Default = .t.
ENDIF
Note that this assumes that any default command buttons are directly on the form,
and not in a non-form container such as a container or page. It fails to find a
command button not directly on the form.
REFERENCES
==========
(c) Microsoft Corporation 1998, All Rights Reserved.
Contributions by Jim Saunders, Microsoft Corporation
Additional query words: kbVFp500abug kbOOP
======================================================================
Keywords :
Technology : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP500a
Version : WINDOWS:5.0,5.0a
Issue type : kbbug
Solution Type : kbpending
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