[BUG] Gtk2::GladeXML using signal_connect_after for everything

[muppet <scott asofyet org>]

in #gtk-perl this evening (times are -0400):
05:16PM <Jodrell> interesting
05:17PM <Jodrell> button_release_event signals don't seem to work on 
glade-generated widgets
05:18PM <Jodrell> anyone care to confirm that for me?
05:20PM <Jodrell> http://jodrell.net/files/button_release_event_test.tgz


i tried it out, and indeed, the signals don't fire.  they do get 
connected, they just never fire.

i loaded that xml file with a trivial C program that does the same 
thing, and the signals fire.

so, dug a little deeper.

the function signal_autoconnect_from_package() is implemented in perl, 
and simply calls signal_autoconnect(), which is implemented in XS, 
passing in _autoconnect_helper as the function to call to connect each 
signal.  this callback is invoked by a private C function in the xs 
file, named connect_func_handler() (which is, in turn, called by 
libglade).  this function passes all the arguments through the standard 
GPerlCallback marshaller gperl_callback_invoke(), which puts something 
on the stack for each item and invokes the perl subroutine.  then we 
wind up in _autoconnect_helper(), which decides whether to call 
signal_connect() or signal_connect_after() based on the $after 
argument.

however, the logic here is broken.  it uses the code

        my $func = defined($after) ? 'signal_connect_after'
                                  : 'signal_connect';

which, since gperl_callback_invoke() always puts a defined value on the 
stack for a G_TYPE_BOOLEAN argument, *always* uses 
'signal_connect_after'.

that means that *every* callback connected by Gtk2::GladeXML runs after 
the default handler.

GtkButton's default handler for button-release-event returns TRUE, 
which stops signal propagation; therefore, your perl-connected handler 
never gets called.


that line should read

        my $func = $after ? 'signal_connect_after' : 'signal_connect';

with that one-line change, the example you posted works great.


there appear to be a couple of unused functions in GladeXML.pm, as 
well, which have the same bug; does anybody use 
Gtk2::GladeXML::handler_connect() ?  i think it (and its helper) should 
be removed.


the attached patch is against Gtk2::GladeXML 1.00 -- please test it out.

Attachment: connect_after_fix.patch
Description: Binary data

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