[gnome-builder] Add Vala template with GTK 4

[Günther Wagner <gwagner src gnome org>]

commit 98d341ee2c923f77f134b002e8278c67578879a5
Author: Yotam Nachum <me yotam net>
Date:   Fri Nov 5 17:52:45 2021 +0200

    Add Vala template with GTK 4

 .../meson-templates/meson-templates.gresource.xml  |  3 ++
 src/plugins/meson-templates/meson_templates.py     |  7 ++--
 .../resources/src/application-gtk4.vala            | 40 ++++++++++++++++++++++
 .../meson-templates/resources/src/main-gtk4.vala   |  6 ++++
 .../resources/src/meson-c-vala.build               |  3 ++
 .../meson-templates/resources/src/window-gtk4.vala | 13 +++++++
 6 files changed, 69 insertions(+), 3 deletions(-)
---
diff --git a/src/plugins/meson-templates/meson-templates.gresource.xml 
b/src/plugins/meson-templates/meson-templates.gresource.xml
index 328c6699f..adac6ef63 100644
--- a/src/plugins/meson-templates/meson-templates.gresource.xml
+++ b/src/plugins/meson-templates/meson-templates.gresource.xml
@@ -18,6 +18,7 @@
     <file compressed="true">resources/src/hello.c</file>
     <file compressed="true">resources/src/hello.h</file>
     <file compressed="true">resources/src/application.c</file>
+    <file compressed="true">resources/src/application-gtk4.vala</file>
     <file compressed="true">resources/src/application.h</file>
     <file compressed="true">resources/src/application.rs</file>
     <file compressed="true">resources/src/__init__.py</file>
@@ -36,11 +37,13 @@
     <file compressed="true">resources/src/window.py</file>
     <file compressed="true">resources/src/window-gtk4.py</file>
     <file compressed="true">resources/src/window.vala</file>
+    <file compressed="true">resources/src/window-gtk4.vala</file>
     <file compressed="true">resources/src/config.rs.in</file>
     <file compressed="true">resources/src/config-gtk4.rs.in</file>
     <file compressed="true">resources/src/window.rs</file>
     <file compressed="true">resources/src/window-gtk4.rs</file>
     <file compressed="true">resources/src/main.vala</file>
+    <file compressed="true">resources/src/main-gtk4.vala</file>
     <file compressed="true">resources/src/main-cli.vala</file>
     <file compressed="true">resources/src/hello.py.in</file>
     <file compressed="true">resources/src/main.py</file>
diff --git a/src/plugins/meson-templates/meson_templates.py b/src/plugins/meson-templates/meson_templates.py
index 8ce88d509..4d5483578 100644
--- a/src/plugins/meson-templates/meson_templates.py
+++ b/src/plugins/meson-templates/meson_templates.py
@@ -330,7 +330,7 @@ class GnomeGTK4ProjectTemplate(MesonTemplate):
             _('GNOME Application'),
             'pattern-gnome',
             _('Create a GNOME application with GTK 4'),
-            ['C', 'Rust', 'Python'],
+            ['C', 'Rust', 'Python', 'Vala'],
             0
          )
 
@@ -373,8 +373,9 @@ class GnomeGTK4ProjectTemplate(MesonTemplate):
             resource_name = None
             window_ui_name = None
         elif self.language == 'vala':
-            files['resources/src/main.vala'] = 'src/main.vala'
-            files['resources/src/window.vala'] = 'src/window.vala'
+            files['resources/src/main-gtk4.vala'] = 'src/main.vala'
+            files['resources/src/window-gtk4.vala'] = 'src/window.vala'
+            files['resources/src/application-gtk4.vala'] = 'src/application.vala'
         elif self.language == 'javascript':
             files['resources/src/main.js.tmpl'] = 'src/main.js'
             files['resources/src/hello.js.in'] = 'src/%(appid)s.in'
diff --git a/src/plugins/meson-templates/resources/src/application-gtk4.vala 
b/src/plugins/meson-templates/resources/src/application-gtk4.vala
new file mode 100644
index 000000000..d77d62b7e
--- /dev/null
+++ b/src/plugins/meson-templates/resources/src/application-gtk4.vala
@@ -0,0 +1,40 @@
+{{include "license.vala"}}
+
+namespace {{PreFix}} {
+       public class Application : Gtk.Application {
+               private ActionEntry[] APP_ACTIONS = {
+                       { "about", on_about_action },
+                       { "preferences", on_preferences_action },
+                       { "quit", quit }
+               };
+
+
+               public Application () {
+                       Object (application_id: "{{appid}}", flags: ApplicationFlags.FLAGS_NONE);
+
+                       this.add_action_entries(this.APP_ACTIONS, this);
+                       this.set_accels_for_action("app.quit", {"<primary>q"});
+               }
+
+               public override void activate () {
+                       base.activate();
+                       var win = this.active_window;
+                       if (win == null) {
+                               win = new {{PreFix}}.Window (this);
+                       }
+                       win.present ();
+               }
+
+               private void on_about_action () {
+                       string[] authors = {"{{author}}"};
+                       Gtk.show_about_dialog(this.active_window,
+                                                 "program-name", "{{name}}",
+                                                 "authors", authors,
+                                                 "version", "{{project_version}}");
+               }
+
+               private void on_preferences_action () {
+                       message("app.preferences action activated");
+               }
+       }
+}
diff --git a/src/plugins/meson-templates/resources/src/main-gtk4.vala 
b/src/plugins/meson-templates/resources/src/main-gtk4.vala
new file mode 100644
index 000000000..e8a05c989
--- /dev/null
+++ b/src/plugins/meson-templates/resources/src/main-gtk4.vala
@@ -0,0 +1,6 @@
+{{include "license.vala"}}
+
+int main (string[] args) {
+       var app = new {{PreFix}}.Application ();
+       return app.run (args);
+}
diff --git a/src/plugins/meson-templates/resources/src/meson-c-vala.build 
b/src/plugins/meson-templates/resources/src/meson-c-vala.build
index a9abe1061..013896751 100644
--- a/src/plugins/meson-templates/resources/src/meson-c-vala.build
+++ b/src/plugins/meson-templates/resources/src/meson-c-vala.build
@@ -11,6 +11,9 @@
 {{else if language == "vala"}}
   'main.vala',
   'window.vala',
+  {{if template == "gnome-app-gtk4"}}
+  'application.vala',
+  {{end}}
 {{end}}
 ]
 
diff --git a/src/plugins/meson-templates/resources/src/window-gtk4.vala 
b/src/plugins/meson-templates/resources/src/window-gtk4.vala
new file mode 100644
index 000000000..7ef3be410
--- /dev/null
+++ b/src/plugins/meson-templates/resources/src/window-gtk4.vala
@@ -0,0 +1,13 @@
+{{include "license.vala"}}
+
+namespace {{PreFix}} {
+       [GtkTemplate (ui = "{{appid_path}}/{{ui_file}}")]
+       public class Window : Gtk.ApplicationWindow {
+               [GtkChild]
+               unowned Gtk.Label label;
+
+               public Window (Gtk.Application app) {
+                       Object (application: app);
+               }
+       }
+}