Re: [ruby-gnome2-devel-en] How-To Interfaces

[Thomas M. <ku...@ro...>]

Am 22.07.2016 um 04:13 schrieb Mario Steele:
> Hello Thomas,
>
> What your looking for to allow your Custom Ruby library to work with 
> libpeas, and various other things, that require the GTYPE, is the 
> ability to register it.  To do this, I utilize this method of creating 
> the class name:
>
> module MyModule
>   class MyCustomClass < GLib::Object
>     unless defined? MYCUSTOMCLASS_TYPE
>       MYCUSTOMCLASS_TYPE = self.name.split(":").collect {|x| x.empty? 
> ? nil : x}.compact.join("_")
> type_register(MYCUSTOMCLASS_TYPE)
>     end
>
>     # Proceed with defining my class, and required methods
>   end
> end
>
> This class is a simple class, that inherits from GLib::Object, but can 
> inherit from anything, as long as somewhere in it's ancestry, 
> GLib::Object is a parent class for it.  What the above does is:
>
> Converts MyModule::MyCustomClass to MyModule_MyCustomClass (Or 
> MYMODULE_MYCUSTOMCLASS in C terms), and then calls 
> GLib::Object#type_register() with the class name, which is defined by 
> MYCUSTOMCLASS_TYPE.  I include a defined? check, incase the file is 
> loaded / required multiple times, or somehow re-loaded, the class 
> doesn't accidentally get re-registered with GLib.  Once you have done 
> this, you should be able to associate the 
> MyModule::MyCustomClass::MYCUSTOMCLASS_TYPE (Or just TYPE for short), 
> with libpeas, and have libpeas utilize this.
>
> Hope this helps you out.


Thanks, this helped a bit. Based on your suggestion I found in the 
examples that I should do:

class Foo < GLib::Object
   type_register # this was missing
   […]
end

I can now successfully create a global $foo = Foo.new and in C:

void *(*rbg2gobj)(VALUE obj);
foo = rb_gv_get("$foo");
rbg2gobj = dlsym(NULL, "rbgobj_instance_from_ruby_object");
foo_gobj = rbg2gobj(foo);
assert(G_IS_OBJECT(foo_gobj));

However, I'm still unable to implement the Peas::Activatable interface, 
due to the error message.

When I remove the specific check that throws this from the ruby-gnome2 
code, then I can use the "include Peas::Activatable" statement. Then, 
$foo.is_a?(Peas::Activatable) even returns true. BUT the following fails 
(in C):

assert(PEAS_IS_ACTIVATABLE(foo_gobj));

Doing the "include Peas::Activatable" before or after the type_register 
call doesn't seem to matter.

Best regards