#include <gtk/gtk.h>

/*Callback function in which reacts to the "response" signal. Be sure to place 

it before the function it is called in*/

static void

on_response (GtkDialog *dialog,

             gint       response_id,

             gpointer   user_data)

{

  /*For demonstration purposes, this will show the int value 

  of the response type*/

  g_print ("response is %d\n", response_id);

  /*This will cause the dialog to be destroyed*/

  gtk_widget_destroy (GTK_WIDGET (dialog));

}

/*Callback function in which reacts to the "clicked" signal*/

static void

show_dialog (GtkButton *button,

             gpointer   user_data)

{

  GtkWindow *window = user_data;

  GtkWidget *dialog;

  GtkWidget *content_area;

  GtkWidget *label;

  gint response_id;

  /*Create the dialog window. Modal windows prevent interaction with other 

  windows in the same application*/

  dialog = gtk_dialog_new_with_buttons ("A Gtk+ Dialog", 

                                        window, 

                                        GTK_DIALOG_MODAL, 

                                        GTK_STOCK_OK, 

                                        GTK_RESPONSE_OK, 

                                        NULL);

  /*Create a label and attach it to the content area of the dialog*/

  content_area = gtk_dialog_get_content_area (GTK_DIALOG (dialog));

  label = gtk_label_new ("This demonstrates a dialog with a label");

  gtk_container_add (GTK_CONTAINER (content_area), label);

  /*The main purpose of this is to show dialog's child widget, label*/

  gtk_widget_show_all (dialog);

  /*Connecting the "response" signal from the user to the associated

  callback function*/

  g_signal_connect (GTK_DIALOG (dialog), 

                    "response", 

                    G_CALLBACK (on_response), 

                    NULL);

}

static void

activate (GtkApplication *app,

          gpointer        user_data)

{

  GtkWidget *window;

  GtkWidget *button;

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

  window = gtk_application_window_new (app);

  gtk_window_set_title (GTK_WINDOW (window), "GNOME Button");

  gtk_window_set_default_size (GTK_WINDOW (window), 250, 50);

  /*Create a button with a label, and add it to the window*/

  button = gtk_button_new_with_label ("Click Me");

  gtk_container_add (GTK_CONTAINER (window), button);

  /*Connecting the clicked signal to the callback*/

  g_signal_connect (GTK_BUTTON (button), 

                    "clicked", 

                    G_CALLBACK (show_dialog), 

                    GTK_WINDOW (window));

  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;

}