[gnome-2048/app-menu: 1/3] Move HeaderBar to ui file

[Jan Tojnar <jtojnar src gnome org>]

commit 3e5ed9caf9564eee90e6e74753fddb11a4945202
Author: Jan Tojnar <jtojnar gmail com>
Date:   Thu Oct 4 18:48:47 2018 +0200

    Move HeaderBar to ui file

 data/mainwindow.ui   | 68 +++++++++++++++++++++++++++++++++++++++-------------
 src/application.vala | 20 +++++-----------
 2 files changed, 57 insertions(+), 31 deletions(-)
---
diff --git a/data/mainwindow.ui b/data/mainwindow.ui
index dc6aacb..8baae33 100644
--- a/data/mainwindow.ui
+++ b/data/mainwindow.ui
@@ -1,15 +1,64 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!-- Generated with glade 3.18.1 -->
+<!-- Generated with glade 3.22.1 -->
 <interface>
   <requires lib="gtk+" version="3.12"/>
   <object class="GtkApplicationWindow" id="applicationwindow">
     <property name="can_focus">False</property>
-    <property name="title" translatable="yes">GNOME 2048</property>
     <property name="window_position">center</property>
     <property name="default_width">600</property>
     <property name="default_height">600</property>
     <property name="icon_name">gnome-2048</property>
     <property name="show_menubar">False</property>
+    <child type="titlebar">
+      <object class="GtkHeaderBar" id="headerbar">
+        <property name="visible">True</property>
+        <property name="can_focus">False</property>
+        <property name="title" translatable="yes">New Game</property>
+        <property name="show_close_button">True</property>
+        <child>
+          <object class="GtkButton" id="undo-button">
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="receives_default">True</property>
+            <property name="action_name">app.undo</property>
+            <property name="always_show_image">True</property>
+            <child>
+              <object class="GtkImage">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="icon_name">edit-undo-symbolic</property>
+              </object>
+            </child>
+          </object>
+          <packing>
+            <property name="position">1</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkButton" id="new-game-button">
+            <property name="label" translatable="yes">_New Game</property>
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="receives_default">True</property>
+            <property name="action_name">app.new-game</property>
+            <property name="use_underline">True</property>
+          </object>
+          <packing>
+            <property name="position">2</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel" id="score">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="label" translatable="yes">0</property>
+          </object>
+          <packing>
+            <property name="pack_type">end</property>
+          </packing>
+        </child>
+      </object>
+    </child>
     <child>
       <object class="GtkGrid" id="grid">
         <property name="visible">True</property>
@@ -38,21 +87,6 @@
         <child>
           <placeholder/>
         </child>
-        <child>
-          <placeholder/>
-        </child>
-        <child>
-          <placeholder/>
-        </child>
-        <child>
-          <placeholder/>
-        </child>
-        <child>
-          <placeholder/>
-        </child>
-        <child>
-          <placeholder/>
-        </child>
       </object>
     </child>
   </object>
diff --git a/src/application.vala b/src/application.vala
index 44ca557..b365f6f 100644
--- a/src/application.vala
+++ b/src/application.vala
@@ -214,7 +214,7 @@ public class Application : Gtk.Application
 
         add_window (_window);
 
-        _create_header_bar ();
+        _create_header_bar (builder);
         _create_game_view (builder);
 
         _window.set_events (_window.get_events () | Gdk.EventMask.STRUCTURE_MASK | 
Gdk.EventMask.KEY_PRESS_MASK | Gdk.EventMask.KEY_RELEASE_MASK);
@@ -228,24 +228,16 @@ public class Application : Gtk.Application
         _window.set_geometry_hints (_window, geom, Gdk.WindowHints.MIN_SIZE);
     }
 
-    private void _create_header_bar ()
+    private void _create_header_bar (Builder builder)
     {
-        _header_bar = new HeaderBar ();
-        _header_bar.show_close_button = true;
-        _header_bar.title = "2048";
-        _window.set_titlebar (_header_bar);
+        _header_bar = (HeaderBar) builder.get_object ("headerbar");
 
-        _score = new Label ("0");
-        _header_bar.pack_end (_score);
+        _score = (Label) builder.get_object ("score");
 
-        _undo_button = new Button.from_icon_name ("edit-undo-symbolic");
-        _undo_button.set_action_name ("app.undo");
-        _header_bar.pack_start (_undo_button);
+        _undo_button = (Button) builder.get_object ("undo-button");
         ((SimpleAction) lookup_action ("undo")).set_enabled (false);
 
-        _new_game_button = new Button.with_label (_("New Game"));
-        _new_game_button.set_action_name ("app.new-game");
-        _header_bar.pack_start (_new_game_button);
+        _new_game_button = (Button) builder.get_object ("new-game-button");
     }
 
     private void _create_game_view (Builder builder)