Add sample glade and c file

src/ui/glade/main.glade

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!-- Generated with glade 3.22.1 -->
+<interface>
+  <requires lib="gtk+" version="3.10"/>
+  <object class="GtkApplicationWindow" id="appwin">
+    <property name="can_focus">False</property>
+    <property name="title" translatable="yes">Wifi hotspot</property>
+    <child>
+      <placeholder/>
+    </child>
+    <child>
+      <object class="GtkListBox">
+        <property name="visible">True</property>
+        <property name="can_focus">False</property>
+        <property name="selection_mode">multiple</property>
+      </object>
+    </child>
+  </object>
+</interface>

src/ui/main.c

@@ -0,0 +1,46 @@
+#include <gtk/gtk.h>
+
+static void
+print_hello (GtkWidget *widget,
+             gpointer   data)
+{
+  g_print ("Hello World\n");
+}
+
+static void
+activate (GtkApplication *app,
+          gpointer        user_data)
+{
+  GtkWidget *window;
+  GtkWidget *button;
+  GtkWidget *button_box;
+
+  window = gtk_application_window_new (app);
+  gtk_window_set_title (GTK_WINDOW (window), "Window");
+  gtk_window_set_default_size (GTK_WINDOW (window), 200, 200);
+
+  button_box = gtk_button_box_new (GTK_ORIENTATION_HORIZONTAL);
+  gtk_container_add (GTK_CONTAINER (window), button_box);
+
+  button = gtk_button_new_with_label ("Hello World");
+  g_signal_connect (button, "clicked", G_CALLBACK (print_hello), NULL);
+  g_signal_connect_swapped (button, "clicked", G_CALLBACK (gtk_widget_destroy), window);
+  gtk_container_add (GTK_CONTAINER (button_box), button);
+
+  gtk_widget_show_all (window);
+}
+
+int
+main (int    argc,
+      char **argv)
+{
+  GtkApplication *app;
+  int status;
+
+  app = gtk_application_new ("org.gtk.example", G_APPLICATION_FLAGS_NONE);
+  g_signal_connect (app, "activate", G_CALLBACK (activate), NULL);
+  status = g_application_run (G_APPLICATION (app), argc, argv);
+  g_object_unref (app);
+
+  return status;
+}