Warning: .close(.F.) and CanExit event

[Raymond Lyons]

Not long ago I discovered something that worked years ago had stopped working at some point. Namely, the .F. check flag on a parentform.close(.F.) button no longer triggers the CanExit event like it used to. This is true at least back to V10.5. My CanExit event was important, and that it stopped working went unnoticed by me and my client for a very long time.

Yes, I submitted this as V12 bug but was told that instead of a fix they would just �deprecate� use the .F. check flag, meaning it was being marked as obsolete and warning against its use in the future so that it might eventually be phased out. This means either I have to not use a button with parentform.close(.F.) to close the form (the X still triggers CanExit) or I have to put my CanExit code above parentform.close() on my button. Not a big deal as long as one is aware of the situation, which I suppose is why it doesn't warrant fixing as a bug--if any desktop bugs warrant fixing in these web/mobile days. Also, the Wiki was updated with the deprecation notice, but unless they have recently changed it for new buyers of V12, the V12 Help file will still falsely say (.F.) will trigger the CanExit event.

I'll probably put a link to this in forums for older A5 versions.

Raymond Lyons

form.close.jpg

[martinwcole]

Re: Warning: .close(.F.) and CanExit event

several years ago, this was all changed. If you put cancel() in the canexit event for a form, to close it you need to say
parentform.code.canexit=""
parentform.close()

[Raymond Lyons]

Re: Warning: .close(.F.) and CanExit event

several years ago, this was all changed. If you put cancel() in the canexit event for a form, to close it you need to say
parentform.code.canexit=""
parentform.close()

Martin,

I am not sure I get the point. Since they made the change I was griping about, if you put cancel() in the CanExit event, yes the Windows system X will not close the form, just as it should not, since that is what cancel() is all about. However, your close script does NOT need perentform.code.canexit="" to blank out the CanExit event and close the form. All it needs is parentform.close(). Why? Because a check flag of any value no longer has any effect in the .close() method, so the cancel() [and all else] in the CanExit event will not fire at all, no matter what (unless, of course, you rely only on the Windows system X to close). Anything you had in CanExit would have to go in your parentform.close() button if you want it to be effective. To my mind that is not how it should work, and at some point in the past (v5, v6, v7, v8 or v9) it did work the way I think it should.

If I am wrong, please correct me.

Raymond Lyons

[martinwcole]

Re: Warning: .close(.F.) and CanExit event

Just did some checking in V12.

If you have cancel() in the canexit event of the form, and on a button say a5.close() - it will not close (unless you first say parentform.code.canexit="")

[Raymond Lyons]

Re: Warning: .close(.F.) and CanExit event

Just did some checking in V12.

If you have cancel() in the canexit event of the form, and on a button say a5.close() - it will not close (unless you first say parentform.code.canexit="")

Yes, that's exactly as it should be for a simple A5.close(), i.e. it's what cancel() is all about in a CanExit event. The same should be true for parentform.close() or at least explicitly parentform.close(.F.), but it is not. That is, whereas a simple A5.close() will fire the CanExit event, no simple (by itself) parentform.close() will fire it. I say it used to and still should, and if not then we all need to be aware that parentform.close() will not fire the CanExit no matter what else you do. Thus the code in the CanExit event has to be in the button with parentform.close(). The only reason (I think!) to have anything in a form's CanExit event is so it will fire if the user uses the Windows system X to close the form--or as you point out, so it will fire if you have a button with a simple A5.close(). Or just turn off the Windows system X if you are going to use parentform.close() with whatever was going to be in the CanExit event.

Also, I suppose one could have something, including cancel(), in the CanExit event that will fire with the Windows system X, and then if you want a button with A5.close() to exit A5 entirely, you would need, as you point out, parentform.code.canexit="" to entirely bypass what is in the CanExit event.

Raymond Lyons

[martinwcole]

Re: Warning: .close(.F.) and CanExit event

yes
My approach with all my apps has been to have one form that never ever closes - Master Menu
if that form has cancel() in the canexit event, then one cannot close alpha from other forms with the X - so the only place to put it is in the Master Menu.

If I want to close alpha from some form other than the Master Menu, I say

if is_object(":master menu")
:master menu.code.canexit=""
a5.close()
end if