date-chooser-day: Use a template

This makes the widget easier to maintain.

src/gui/event-editor/event-editor.gresource.xml

@@ -3,6 +3,7 @@
   <gresource prefix="/org/gnome/calendar/ui/event-editor">
     <file compressed="true">gcal-alarm-row.ui</file>
     <file compressed="true">gcal-date-chooser.ui</file>
+    <file compressed="true">gcal-date-chooser-day.ui</file>
     <file compressed="true">gcal-date-selector.ui</file>
     <file compressed="true">gcal-event-editor-dialog.ui</file>
     <file compressed="true">gcal-multi-choice.ui</file>

src/gui/event-editor/gcal-date-chooser-day.c

@@ -50,30 +50,19 @@ static void
 gcal_date_chooser_day_class_init (GcalDateChooserDayClass *class)
 {
   GObjectClass *object_class = G_OBJECT_CLASS (class);
+  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class);
 
   object_class->dispose = gcal_date_chooser_day_dispose;
+
+  gtk_widget_class_set_template_from_resource (widget_class, "/org/gnome/calendar/ui/event-editor/gcal-date-chooser-day.ui");
+
+  gtk_widget_class_bind_template_child (widget_class, GcalDateChooserDay, label);
 }
 
 static void
 gcal_date_chooser_day_init (GcalDateChooserDay *self)
 {
-  GtkWidget *widget = GTK_WIDGET (self);
+  gtk_widget_init_template (GTK_WIDGET (self));
-
-  gtk_widget_set_halign (widget, GTK_ALIGN_CENTER);
-  gtk_widget_set_valign (widget, GTK_ALIGN_CENTER);
-
-  gtk_widget_set_can_focus (widget, TRUE);
-  gtk_widget_add_css_class (widget, "circular");
-  gtk_widget_add_css_class (widget, "day");
-  gtk_widget_add_css_class (widget, "flat");
-
-  self->label = gtk_label_new ("");
-  gtk_widget_set_halign (self->label, GTK_ALIGN_CENTER);
-  gtk_widget_set_valign (self->label, GTK_ALIGN_CENTER);
-  gtk_widget_set_hexpand (self->label, TRUE);
-  gtk_widget_set_vexpand (self->label, TRUE);
-
-  gtk_button_set_child (GTK_BUTTON (self), self->label);
 }
 
 GtkWidget*

src/gui/event-editor/gcal-date-chooser-day.ui

@@ -0,0 +1,20 @@
+<?xml version="1.0"?>
+<interface>
+  <template class="GcalDateChooserDay" parent="GtkButton">
+    <property name="halign">center</property>
+    <property name="valign">center</property>
+    <style>
+      <class name="circular"/>
+      <class name="day"/>
+      <class name="flat"/>
+    </style>
+    <child>
+      <object class="GtkLabel" id="label">
+        <property name="halign">center</property>
+        <property name="hexpand">True</property>
+        <property name="valign">center</property>
+        <property name="vexpand">True</property>
+      </object>
+    </child>
+  </template>
+</interface>