[gtkada] attribute must be discrete type

[Matthias Teege]

Moin,

I use glade to create a treeview and add a signal on row_activated.
Glade create the following callback:

procedure On_Treeview1_Row_Activated
	    (Object : access Gtk_Tree_View_Record'Class;
             Params : Gtk.Arguments.Gtk_Args)
is
      Arg1 : Gtk_Tree_Path := Gtk_Tree_Path'Val (To_Gint (Params, 1));
      Arg2 : Gtk_Tree_View_Column := Gtk_Tree_View_Column'Val (To_Gint (Params, 2));
begin
      null;
end On_Treeview1_Row_Activated;

This code doesnt compile because of:

gnatgcc -c -g -I/usr/lib/ada/adainclude/gtkada -gnatq -gnatQ window1_pkg-callbacks.adb
window1_pkg-callbacks.adb:69:31: prefix of "Val" attribute must be discrete type
window1_pkg-callbacks.adb:70:38: prefix of "Val" attribute must be discrete type
gnatmake: "window1_pkg-callbacks.adb" compilation error

What is the problem here?
Matthias

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