[DUG] Compnent creation question

[Paul A Norman]

I Didn't get through all the posts' texts, but don't we need to count
backwards when freeing list type thingies?

        for Counter := 0 to Self.Items.Count - 1 do begin

Something like . ....

for Counter :=  Self.Items.Count - 1down to 0 do begin
Paul
2008/10/16 Robert martin <rob at chreos.co.nz>

> (Resend didn't seem to come through last time)
>
> Hi
>
> Thanks Kyley.
>
> I actually managed to get that somewhat working but picked up a number
> of other issues.  for now I have given up and just overridden the clear
> procedure to free the items.  Not great but for my purposes adequate.
>
>
> Thanks to all for suggestions and comments.
> Rob
>
>
> Kyley Harris wrote:
> > Override:
> >     function GetItemsClass: TCustomComboBoxStringsClass; virtual;
> > abstract;
> > Create your own subclass of TCustomComboBoxStrings and override the
> > Item add and Item delete routines. You need to place a synched copy of
> > your objects into a seperate list so that when the windows handle to
> > the combobox is released or recreated you don't loose your object
> > pointers. you can also add asserts or tests on the combobox.handle
> > rather than letting it crash all the time. then on the destroy of your
> > TCustomCombobox strings free all the objects in the list.. This would
> > be easiest by using a TObjectList with owns objects = true.
> >
> >
> >
> > On Wed, Oct 15, 2008 at 4:22 PM, Robert martin <rob at chreos.co.nz
>  > <mailto:rob at chreos.co.nz>> wrote:
> >
> >     Hi
> >
> >     Just trying to make a TComboBox that automatically frees its items.
> >
> >     I have the following code in the destructor
> >
> >        if (fAutomaticallyFreeObjects = True)
> >                and ((csDesigning in ComponentState) = False) then begin
> >            try
> >                for Counter := 0 to Self.Items.Count - 1 do begin
> >                    O := Items.Objects[Counter];
> >                    if (O <> nil) then begin
> >                       O.Free;
> >                    end;
> >                end;
> >            except
> >                on e: exception do begin
> >                    ShowMessage(IntToStr(i) + ' ' + 'Attempting to
> >     automatically free object memory.  The following error occured...' +
> >     #13#13 + e.message);
> >                end;
> >            end;
> >        end;
> >
> >
> >     I get a 'Control '' has no parent error.  This happens when
> attempting
> >     to access the .Items property.  My custom error handling does not
> >     trigger.
> >
> >     Any suggestions ?
> >
> >     Thanks
> >     Rob
> >     _______________________________________________
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> >
> >
> >
> >
> > --
> > Kyley Harris
> > Harris Software
> > +64-21-671-821
> > ------------------------------------------------------------------------
>  >
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