<page xmlns="http://projectmallard.org/1.0/" xmlns:its="http://www.w3.org/2005/11/its" xmlns:xi="http://www.w3.org/2001/XInclude" type="guide" style="task" id="spinbutton.c" xml:lang="ca">

  <info>

    <title type="text">SpinButton (C)</title>

    <link type="guide" xref="c#entry"/>

    <link type="seealso" xref="scale.c"/>

    <link type="seealso" xref="label.c"/>

    <link type="seealso" xref="grid.c"/>

    <revision version="0.2" date="2012-07-05" status="draft"/>

    <credit type="author copyright">

      <name>Monica Kochofar</name>

      <email its:translate="no">monicakochofar@gmail.com</email>

      <years>2012</years>

    </credit>

    <desc>Retrieve an integer or floating point number</desc>

  </info>

  <title>SpinButton</title>

   <media type="image" mime="image/png" src="media/spinbutton.png"/>

    
Choose a number, by entering it or by clicking on the -/+ buttons!

#include <gtk/gtk.h>

/* This is the callback function. 

 * It is a handler function which reacts to the signal. 

 * In this case, it will notify the user the value of their spinbutton 

 * as a label.

 */

static void

spin_clicked (GtkSpinButton *spinbutton,

              gpointer       user_data)

{

   GtkWidget *label = user_data;

   gint value = gtk_spin_button_get_value_as_int (spinbutton);

   /* %d - Is used when printing integers.

    * Note: Using g_strdup_printf returns a string that must be freed. 

    * (In which is done below)

    */

   gchar *str = g_strdup_printf ("The number you selected is %d.", value);

   gtk_label_set_text (GTK_LABEL (label), str);

   g_free(str);

}

static void

activate (GtkApplication *app,

          gpointer        user_data)

{

  /* Declare variables */

  GtkWidget *window;

  GtkWidget *label;

  GtkWidget *grid;

  GtkWidget *spin_button;

  GtkAdjustment *adjustment;

  /* Create a window with a title, a border width, and a default size */

  window = gtk_application_window_new (app);

  gtk_window_set_title (GTK_WINDOW (window), "SpinButton Example");

  gtk_window_set_default_size (GTK_WINDOW (window), 210, 70);

  gtk_container_set_border_width (GTK_CONTAINER (window), 5);

  /* Create a label to be shown in the window */

  label = gtk_label_new ("Choose a number");

  /* Create an adjustment representing an adjustable bounded value */

  adjustment = gtk_adjustment_new (0, 0, 100, 1, 0, 0);

  /* Create a spin button that is to be as wide as possible */

  spin_button = gtk_spin_button_new (adjustment, 1, 0);

  gtk_widget_set_hexpand (spin_button, TRUE);

  /* Connecting the "value-changed" signal for the spinbutton 

   * to the appropriate callback function. 

   */

  g_signal_connect (spin_button, 

                    "value-changed", 

                    G_CALLBACK (spin_clicked), 

                    label);

  /* Create a grid and arrange everything accordingly */

  grid = gtk_grid_new ();

  gtk_grid_set_column_spacing (GTK_GRID (grid), 10);

  gtk_grid_set_column_homogeneous (GTK_GRID (grid), TRUE);

  gtk_grid_attach (GTK_GRID (grid), spin_button, 0, 0, 1, 1);

  gtk_grid_attach (GTK_GRID (grid), label, 0, 1, 1, 1);

  gtk_container_add (GTK_CONTAINER (window), grid);

  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;

}

  In this sample we used the following:

<list>

  <item>
<link href="http://developer.gnome.org/gtk3/3.4/GtkApplication.html">GtkApplication</link>
</item>

  <item>
<link href="http://developer.gnome.org/gtk3/3.4/GtkWindow.html">GtkWindow</link>
</item>

  <item>
<link href="http://developer.gnome.org/gtk3/stable/GtkSpinButton.html">GtkSpinButton</link>
</item>

  <item>
<link href="http://developer.gnome.org/gtk3/stable/GtkLabel.html">GtkLabel</link>
</item>

  <item>
<link href="http://developer.gnome.org/gtk3/stable/GtkAdjustment.html">GtkAdjustment</link>
</item>

  <item>
<link href="http://developer.gnome.org/gtk3/stable/GtkGrid.html">GtkGrid</link>
</item>

</list>

</page>