Kurt
I assume you are basing this on the fact that any app written for Win32 gets
'shut down' at least a few times a day? <g>
Also dynamically created comps may (create/free) for the life of the app so
you would be coding and memory 'leak'
Neven
----- Original Message -----
From: Kurt <[EMAIL PROTECTED]>
To: Multiple recipients of list delphi <[EMAIL PROTECTED]>
Sent: Thursday, 30 November 2000 09:30
Subject: Re: [DUG]: Component Creation 101
> Regarding 4
> doesn't the application free _all_ its assigned memory when it is
> closed? Or would some component that was constructed with a nil owner
> keep using that memory until some other event - if so, when would that
> be - reboot/shutdown/next Delphi app started ? I'm aware this is not a
> nice way of doing things, but just wondered the official reason.
>
> Cheers,
> Kurt.
>
> Neven MacEwan wrote:
> >
> > Chrissy
> >
> > Just a few basics
> >
> > 1/ In Delphi you almost never have to use pointers and new() is really
for
> > non-object use
> > 2/ A TComponent derived class can own other TComponents (which may own
> > other...) See TComponent.Components array & TComponent.ComponentCount
> > (simarly TWinControl implement Controls array and ControlCount)
> > 3/ By default a 'Form' (a TComponent Derivative) owns all the components
on
> > it
> > 4/ The 'owner' is passed to the constuctor if the 'owner' is nil then
> > something has to destroy it
> > This is because the TComponent constructor 'registers' itself with the
owner
> > (who maintains a list of it components)
> > so that it knows who to destroy (in its destructor).
> > 5/ It is imperitive to understand the difference between Parent and
Owner
> > 6/ It is imperitive to understand the difference between
> > TObject/TPersistent/TComponent
> >
> > I think in various versions of Delphi the overhead of components
traversing
> > lists and registering a list of components (and the
> > sequencing of destuction) was annoying so it became fashionable to
> > programmatically create components with a nil Owner
> > and Destroy them yourself however in my experience it is better to go
throuh
> > the pain of passing an owner and working though
> > the consequences (esp with visible components because there is
invariably a
> > link between ownership and parenthood) than
> > continue the 'trick'
> >
> > Simple Aint it
> > HTH
> >
> > Regards Neven
> > N.K. MacEwan B.E. E&E
> > Ph 649 574 0027
> > Fax 649 570 2706
> >
> > "A truth denied the light of action will wither to a promise, propaganda
and
> > then a lie"
> >
>
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