Re: Glib errors while deleting Gtk::ComboBoxEntryText. help needed


As you should know, the GTKmm-Libraries are only wrappers of the C-Libraries.
These have been in use for about 10 years, and should be stable at all.

The only thing that you can really do wrong in GTKmm, is to use threads
to call GTK-Functions in them as GTKmm is (because of GTK) not thread-save.
This will result in GTK or Glib::Mainloop-Errors, or simply undefined behaviour.

Moreover you should be able to reduce the code to locate the error. Simplest way is to use a debugger, export the variables and rewrite the small active code-part
with use of this exported Variables.

With regards


Well, I'm afraid I cant.
Anyway Its a quite complex system with about 4 libraries involved on this
specific content-change event. I can not reproduce the problem in a reduced
code of similar characteristics.

I thought it could be a Gtkmm issue because, as I said, there where
different Glib errors reported, only changing the connected widget's signal.
I can also say that my program still works as expected, as if the Glib
errors had no effect.

I can say as a clue that I delete the combo box widget, its container and
other widgets that can be related in one or other way with the combo box
while I'm still processing the signal changed event callback. I'm not really
sure if this behavior is supported, but I suppose I can delete a button
widget while processing its button pressed callback function, and this is
the same use case.

I know its pretty difficult to give any help without seeing the code. Tell
me if I can do anything else it can help you. Meanwhile I'll continue
debugging the problem and if finally is a Gtkmm issue I'll make a small
program to illustrate it.

Thanks anyway.

Галымжан Кожаев wrote:
Could you send a piece of your code ?

2010/1/15, siagogam<siagogam terra es>:
Hi to all:

Im just getting this error while deleting the Gtk::ComboBoxEntryText

GLib-GObject-WARNING **: instance with invalid (NULL) class pointer
GLib-GObject-CRITICAL **: g_signal_handlers_unblock_matched: assertion
`G_TYPE_CHECK_INSTANCE (instance)' failed
GLib-GObject-CRITICAL **: g_object_notify: assertion `G_IS_OBJECT

i've been debugging a little bit my program and i've concluded that if I
will get this error if I try to release the widget while gtkcombo ->
get_entry() ->  signal_changed() is still connected

if I connect the gtkcombo ->  signal_changed() instead of connecting
->  get_entry() ->  signal_changed() i get this error:

GLib-GObject-CRITICAL **: g_object_notify: assertion `G_IS_OBJECT

so probably this last one has nothing to do with the other two.

Is there a known bug on this issue?
am i doing something wrong?

any kind of help or idea is appreciated.

thanks in advance

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