Gio::Action and radio buttons

[Yann Leydier <yann leydier info>]

Hi,

as far as I understand, the replacement of Gtk::RadioAction is a 
Gio::Action with an integer or string state.

I create RadioToolButtons with descriptions like this:
<object class='GtkRadioToolButton' id='show-other'>
    <property name='visible'>True</property>
    <property name='can_focus'>False</property>
    <property name='tooltip_text' translatable='yes'>Show result 
image</property>
    <property name='action_name'>app.show-image</property>
    <property name='action_target'>3</property>
</object>"
where app.show-image is a Gio::SimpleAction with an integer state.

However, all the radio buttons are always active, where I was expecting 
only the one with a target that matches the action's state to be active. 
Nothing changes when I call change_state on the action.

Did I do something wrong?

Thanks,
yann