Hi,
Just to reply to :
"...
- For setting properties on the parent in a constructor what is wrong with
this.property_name = xyz;
..."
It is not wrong, but the behaviour is not exactly the same.
I get stuck on this before I realize the error.
When you use the constructed() method (to initialize ui by exemple), if you
use "this.something = some_arg", something isn't initialized in the
constructed() method, but it is when you use Object(something: some_arg).
Approximative generated C code for a class "Ns.ClassName" without Object()
call in the constructor :
NsClassName* ns_class_name_construct (GType object_type, type some_arg) {
NsClassName * self = NULL;
...
self = (NsClassName*) g_object_new (object_type, NULL);
...
ns_class_name_set_something (self, some_arg);
...
return self;
}
the constructed() method is called at the end of g_object_new(), so
ns_class_name_set_something() isn't called yet.
Same thing with a the use of Object() :
NsClassName* ns_class_name_construct (GType object_type, type some_arg) {
NsClassName * self = NULL;
...
self = (NsClassName*) g_object_new (object_type, "something", some_arg,
NULL);
...
return self;
}
In this case, when the constructed() method is called something has the
value some_arg.
Regards,
Luc.
Le lun. 27 juin 2016 à 17:30, Al Thomas <astav...@yahoo.co.uk> a écrit :
>
> ------------------------------
> *From:* Luc Chante <luc.cha...@gmail.com>
> *Sent:* Monday, 27 June 2016, 11:36
> *Subject:* Re: [Vala] getting started with vala and glade
>
>
> I think it would be a good start to use gtk templates.
> So you can use your ui file and create the ApplicationWindow by it's
> constructor (which takes an Application instance).
>
> Join to this mail a really simple example using ui file and gtk templates.
> Tested with msys 2.
>
> This is a great start for a code sample on the wiki, maybe:
> https://wiki.gnome.org/Projects/Vala/GTKTemplateSample
>
> As a code sample I have a couple of doubts about the current coding style:
>
> - I think the main() method should be on its own, not buried in an object
>
> - For setting properties on the parent in a constructor what is wrong with
> this.property_name = xyz;
> instead of using Vala specific GObject plumbing like Object(
> property_name: value );
> Although these low level GObject features exist they add additional
> complexity when
> initially learning the language and are unnecessary in most cases
>
> So a revised main.vala:
>
> /**
> * Application
> */
> public class MyApplication : Gtk.Application
> {
> public MyApplication(string? app_id = null, ApplicationFlags flags =
> ApplicationFlags.FLAGS_NONE)
> {
> if (app_id != null && Application.id_is_valid (app_id) == false) {
> error( "Application ID is not valid");
> }
> this.application_id = app_id;
> this.flags = flags;
> }
>
> public override void activate () {
> var window = new Template.ApplicationWindow (this);
> window.present ();
> }
> }
>
> /**
> * Application window
> */
> [GtkTemplate(ui = "/template/window.ui")]
> public class Template.ApplicationWindow : Gtk.ApplicationWindow
> {
> [GtkChild]
> Gtk.Button test_button;
>
> public ApplicationWindow(Gtk.Application application)
> {
> this.application = application;
> }
>
> [GtkCallback]
> public void on_test_button_clicked(Gtk.Button button)
> {
> GLib.message("Button clicked !!!");
> }
> }
>
> /** Application entry point */
> public static int main(string[] args)
> {
> var app = new MyApplication ("my.application");
> return app.run (args);
> }
>
> Finally as a more generic way to compile use:
>
> glib-compile-resources --sourcedir ./ --generate-source --target
> resources.c template.gresource.xml
> valac --pkg gtk+-3.0 --target-glib 2.38 --gresources
> template.gresource.xml resources.c main.vala --output myapp
>
> The Makefile is nice though.
>
> Regards,
>
> Al
>
>
_______________________________________________
vala-list mailing list
vala-list@gnome.org
https://mail.gnome.org/mailman/listinfo/vala-list
