Re: reference pointer in the custom container (was: Re: preferred way to destroy a window)

[Paul Pogonyshev <pogonyshev gmx net>]

Murray Cumming wrote:

> Glib::RefPtr is not for use with widgets. It is for use with classes that
> do not allow you to use them without RefPtr. See the gtkmm book for more
> detailed documentaiton. If you did use it then you would have to be a lot
> more careful about whether or not it had a starting reference.

In plain GTK+ it is common to reference a widget to make sure it is not
destroyed before the reference keeper.  And widgets are not different from
other objects in this respect.

> If what you actually want is for the child to be deleted automatically
> when the window is deleted, then just use Gtk::manage(). Again, this is in
> gtkmm book.
> http://www.gtkmm.org/docs/gtkmm-2.4/docs/tutorial/html/ch03s02.html
> and
> http://www.gtkmm.org/docs/gtkmm-2.4/docs/tutorial/html/ch20.html
>
> Do make sure you've read that Basics chapter. It will save you lots of time.

I have read the books.  It says nothing about how the manage() works and I
assumed all the way that it destroys C++ object when underlying C object's
reference count drops to zero i.e. when C object is destroyed.  In this case,
an additional RefPtr shouldn't hurt, but apparently it does.  And I consider
it wrong.

Anyway, RefPtr is not very important in _this_ case.

Paul