Re: [Vala] Vala does not register string[] properties

[Abderrahim Kitouni <a kitouni gmail com>]

Hi,

2010/3/25 Julian Andres Klode <jak jak-linux org>:
> Hi,
>
> string[] properties are not installed via g_object_class_install_property (),
> which makes it impossible for json-glib to deserialize objects with array
> members.
I'm having the exact problem, with the exact use case [1], I was just
too lazy to  post it :-)

> In the json-glib test code, I read the following:
>  g_object_class_install_property (gobject_class,
>                                   PROP_MAH,
>                                   g_param_spec_boxed ("mah", "Mah", "Mah",
>                                                       G_TYPE_STRV,
>                                                       G_PARAM_READWRITE));
> Whereas mah is:
>  gchar **mah;
>
> Would it be possible for Vala to do the same, so I don't have to convert
> arrays manually when working with json-glib?
It should be possible, but needs patching Vala. Making Vala register
the property is just something like :

diff --git a/codegen/valagobjectmodule.vala b/codegen/valagobjectmodule.vala
--- a/codegen/valagobjectmodule.vala
+++ b/codegen/valagobjectmodule.vala
@@ -717,7 +725,7 @@ internal class Vala.GObjectModule : GTypeModule {
                        return false;
                }

-               if (prop.property_type is ArrayType) {
+               if (prop.property_type is ArrayType &&
prop.property_type.get_type_id () == null) {
                        return false;
                }

but the problem is in the *_[sg]et_property function : the property
setter/getter takes an extra "length" argument. Setting the property
should be trivial (I think we can just pass -1 as the array in a
GValue should null-terminated), but the getter may need some work.
(anyone familiar with vala's codegen?)

HTH,
Abderrahim

[1] I'm using json-glib to implement a vala parser for BuilDj
http://live.gnome.org/BuilDj