Re: [Vala] Access the "klass" parameter of a class_init() function in vala with "static construct"

[Sébastien Wilmet <sebastien wilmet gmail com>]

2010/8/1 Evan Nemerson <evan coeus-group com>

> On Sat, 2010-07-31 at 22:08 +0200, Sébastien Wilmet wrote:
> > 2010/7/31 Evan Nemerson <evan coeus-group com>
> >         On Sat, 2010-07-31 at 17:59 +0200, Sébastien Wilmet wrote:
> >         > Hello!
> >         >
> >         > What I want to do is to implement a GtkAction derived class
> >         which sets
> >         > GtkActionClass:toolbar_item_type to
> >         GTK_TYPE_MENU_TOOL_BUTTON in its
> >         > class_init function.
> >
> >
> >         Vala doesn't currently expose *Class structs in the bindings,
> >         so AFAIK
> >         what you're talking about can't be done easily. I'm not
> >         exactly an
> >         expert on GObject, but I think you should be able to hack
> >         something
> >         together by going creating bindings for GtkActionClass then
> >         getting
> >         access to it with GLib.Object.get_class. This is untested, but
> >         you
> >         should get the idea:
> >
> >
> >         /* In a vapi */
> >         [Compact, CCode (cname = "GtkActionClass")]
> >         public class GtkActionClass {
> >          public GLib.Type menu_item_type;
> >          public GLib.Type toolbar_item_type;
> >         }
> >
> >         /* Your code */
> >         unowned GtkActionClass ac = (GtkActionClass) this.get_class
> >         ();
> >         ac.toolbar_item_type = typeof (MenuToolButton);
> >
> >
> > I have this error:
> > error: Access to instance member `GLib.Object.get_class' denied
>
> You aren't going to be able to access it from a static construct block.
> Try it from within a regular construct block.
Yeah it works! Thanks. I thought it was an obligation to put the code in the
static construct block since in C it is in *class_init().

So here is my code (with the vapi you wrote):

using Gtk;

public class MenuToolAction : Action
{
    public MenuToolAction (string name, string? label, string? tooltip,
string? stock_id)
    {
        GLib.Object (name: name, label: label, tooltip: tooltip, stock_id:
stock_id);
        unowned GtkActionClass ac = (GtkActionClass) get_class ();
        ac.toolbar_item_type = typeof (MenuToolButton);
    }
}