#include <gtk/gtk.h>

/*This is the callback function. It is a handler function 

which reacts to the signal. In this case, it will grab the 

text input from the entry box and print out a line to the user.*/

static void

on_activate (GtkEntry *entry,

             gpointer  user_data)

{

  const char *name;

  name = gtk_entry_get_text (entry);

  g_print ("\nHello %s!\n\n", name);

}

static void

activate (GtkApplication *app,

          gpointer        user_data)

{

  GtkWidget *window;

  GtkWidget *entry_box;

  /*Create a window with a title, a default size, 

  and a set border width*/

  window = gtk_application_window_new (app);

  gtk_window_set_title (GTK_WINDOW (window), "What is your name?");

  gtk_window_set_default_size (GTK_WINDOW (window), 300, 100);

  gtk_container_set_border_width (GTK_CONTAINER (window), 10);

  /*Create a new entry box, and add it to the window*/

  entry_box = gtk_entry_new ();

  gtk_container_add (GTK_CONTAINER (window), entry_box);

  /*Connecting the activate signal to the callback*/

  g_signal_connect (GTK_ENTRY (entry_box), "activate", 

                    G_CALLBACK (on_activate), NULL);

  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;

}