#include <gtk/gtk.h>GtkWidget *hscale, *vscale;static void cb_pos_menu_select( GtkWidget       *item,                                GtkPositionType  pos ){    /* Set the value position on both scale widgets */    gtk_scale_set_value_pos (GTK_SCALE (hscale), pos);    gtk_scale_set_value_pos (GTK_SCALE (vscale), pos);}static void cb_update_menu_select( GtkWidget     *item,                                   GtkUpdateType  policy ){    /* Set the update policy for both scale widgets */    gtk_range_set_update_policy (GTK_RANGE (hscale), policy);    gtk_range_set_update_policy (GTK_RANGE (vscale), policy);}static void cb_digits_scale( GtkAdjustment *adj ){    /* Set the number of decimal places to which adj->value is rounded */    gtk_scale_set_digits (GTK_SCALE (hscale), (gint) adj->value);    gtk_scale_set_digits (GTK_SCALE (vscale), (gint) adj->value);}static void cb_page_size( GtkAdjustment *get,                          GtkAdjustment *set ){    /* Set the page size and page increment size of the sample     * adjustment to the value specified by the "Page Size" scale */    set->page_size = get->value;    set->page_increment = get->value;    /* This sets the adjustment and makes it emit the "changed" signal to        reconfigure all the widgets that are attached to this signal.  */    gtk_adjustment_set_value (set, CLAMP (set->value,					  set->lower,					  (set->upper - set->page_size)));    g_signal_emit_by_name(G_OBJECT(set), "changed");}static void cb_draw_value( GtkToggleButton *button ){    /* Turn the value display on the scale widgets off or on depending     *  on the state of the checkbutton */    gtk_scale_set_draw_value (GTK_SCALE (hscale), button->active);    gtk_scale_set_draw_value (GTK_SCALE (vscale), button->active);  }/* Convenience functions */static GtkWidget *make_menu_item ( gchar     *name,                                   GCallback  callback,                                   gpointer   data ){    GtkWidget *item;      item = gtk_menu_item_new_with_label (name);    g_signal_connect (G_OBJECT (item), "activate",	              callback, (gpointer) data);    gtk_widget_show (item);    return item;}static void scale_set_default_values( GtkScale *scale ){    gtk_range_set_update_policy (GTK_RANGE (scale),                                 GTK_UPDATE_CONTINUOUS);    gtk_scale_set_digits (scale, 1);    gtk_scale_set_value_pos (scale, GTK_POS_TOP);    gtk_scale_set_draw_value (scale, TRUE);}/* makes the sample window */static void create_range_controls( void ){    GtkWidget *window;    GtkWidget *box1, *box2, *box3;    GtkWidget *button;    GtkWidget *scrollbar;    GtkWidget *separator;    GtkWidget *opt, *menu, *item;    GtkWidget *label;    GtkWidget *scale;    GtkObject *adj1, *adj2;    /* Standard window-creating stuff */    window = gtk_window_new (GTK_WINDOW_TOPLEVEL);    g_signal_connect (G_OBJECT (window), "destroy",                      G_CALLBACK (gtk_main_quit),                      NULL);    gtk_window_set_title (GTK_WINDOW (window), "range controls");    box1 = gtk_vbox_new (FALSE, 0);    gtk_container_add (GTK_CONTAINER (window), box1);    gtk_widget_show (box1);    box2 = gtk_hbox_new (FALSE, 10);    gtk_container_set_border_width (GTK_CONTAINER (box2), 10);    gtk_box_pack_start (GTK_BOX (box1), box2, TRUE, TRUE, 0);    gtk_widget_show (box2);    /* value, lower, upper, step_increment, page_increment, page_size */    /* Note that the page_size value only makes a difference for     * scrollbar widgets, and the highest value you'll get is actually     * (upper - page_size). */    adj1 = gtk_adjustment_new (0.0, 0.0, 101.0, 0.1, 1.0, 1.0);      vscale = gtk_vscale_new (GTK_ADJUSTMENT (adj1));    scale_set_default_values (GTK_SCALE (vscale));    gtk_box_pack_start (GTK_BOX (box2), vscale, TRUE, TRUE, 0);    gtk_widget_show (vscale);    box3 = gtk_vbox_new (FALSE, 10);    gtk_box_pack_start (GTK_BOX (box2), box3, TRUE, TRUE, 0);    gtk_widget_show (box3);    /* Reuse the same adjustment */    hscale = gtk_hscale_new (GTK_ADJUSTMENT (adj1));    gtk_widget_set_size_request (GTK_WIDGET (hscale), 200, -1);    scale_set_default_values (GTK_SCALE (hscale));    gtk_box_pack_start (GTK_BOX (box3), hscale, TRUE, TRUE, 0);    gtk_widget_show (hscale);    /* Reuse the same adjustment again */    scrollbar = gtk_hscrollbar_new (GTK_ADJUSTMENT (adj1));    /* Notice how this causes the scales to always be updated     * continuously when the scrollbar is moved */    gtk_range_set_update_policy (GTK_RANGE (scrollbar),                                  GTK_UPDATE_CONTINUOUS);    gtk_box_pack_start (GTK_BOX (box3), scrollbar, TRUE, TRUE, 0);    gtk_widget_show (scrollbar);    box2 = gtk_hbox_new (FALSE, 10);    gtk_container_set_border_width (GTK_CONTAINER (box2), 10);    gtk_box_pack_start (GTK_BOX (box1), box2, TRUE, TRUE, 0);    gtk_widget_show (box2);    /* A checkbutton to control whether the value is displayed or not */    button = gtk_check_button_new_with_label("Display value on scale widgets");    gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (button), TRUE);    g_signal_connect (G_OBJECT (button), "toggled",                      G_CALLBACK (cb_draw_value), NULL);    gtk_box_pack_start (GTK_BOX (box2), button, TRUE, TRUE, 0);    gtk_widget_show (button);      box2 = gtk_hbox_new (FALSE, 10);    gtk_container_set_border_width (GTK_CONTAINER (box2), 10);    /* An option menu to change the position of the value */    label = gtk_label_new ("Scale Value Position:");    gtk_box_pack_start (GTK_BOX (box2), label, FALSE, FALSE, 0);    gtk_widget_show (label);      opt = gtk_option_menu_new ();    menu = gtk_menu_new ();    item = make_menu_item ("Top",                           G_CALLBACK (cb_pos_menu_select),                           GINT_TO_POINTER (GTK_POS_TOP));    gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);      item = make_menu_item ("Bottom", G_CALLBACK (cb_pos_menu_select),                            GINT_TO_POINTER (GTK_POS_BOTTOM));    gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);      item = make_menu_item ("Left", G_CALLBACK (cb_pos_menu_select),                           GINT_TO_POINTER (GTK_POS_LEFT));    gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);      item = make_menu_item ("Right", G_CALLBACK (cb_pos_menu_select),                           GINT_TO_POINTER (GTK_POS_RIGHT));    gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);      gtk_option_menu_set_menu (GTK_OPTION_MENU (opt), menu);    gtk_box_pack_start (GTK_BOX (box2), opt, TRUE, TRUE, 0);    gtk_widget_show (opt);    gtk_box_pack_start (GTK_BOX (box1), box2, TRUE, TRUE, 0);    gtk_widget_show (box2);    box2 = gtk_hbox_new (FALSE, 10);    gtk_container_set_border_width (GTK_CONTAINER (box2), 10);    /* Yet another option menu, this time for the update policy of the     * scale widgets */    label = gtk_label_new ("Scale Update Policy:");    gtk_box_pack_start (GTK_BOX (box2), label, FALSE, FALSE, 0);    gtk_widget_show (label);      opt = gtk_option_menu_new ();    menu = gtk_menu_new ();      item = make_menu_item ("Continuous",                           G_CALLBACK (cb_update_menu_select),                           GINT_TO_POINTER (GTK_UPDATE_CONTINUOUS));    gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);      item = make_menu_item ("Discontinuous",                           G_CALLBACK (cb_update_menu_select),                           GINT_TO_POINTER (GTK_UPDATE_DISCONTINUOUS));    gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);      item = make_menu_item ("Delayed",                           G_CALLBACK (cb_update_menu_select),                           GINT_TO_POINTER (GTK_UPDATE_DELAYED));    gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);      gtk_option_menu_set_menu (GTK_OPTION_MENU (opt), menu);    gtk_box_pack_start (GTK_BOX (box2), opt, TRUE, TRUE, 0);    gtk_widget_show (opt);      gtk_box_pack_start (GTK_BOX (box1), box2, TRUE, TRUE, 0);    gtk_widget_show (box2);    box2 = gtk_hbox_new (FALSE, 10);    gtk_container_set_border_width (GTK_CONTAINER (box2), 10);      /* An HScale widget for adjusting the number of digits on the     * sample scales. */    label = gtk_label_new ("Scale Digits:");    gtk_box_pack_start (GTK_BOX (box2), label, FALSE, FALSE, 0);    gtk_widget_show (label);    adj2 = gtk_adjustment_new (1.0, 0.0, 5.0, 1.0, 1.0, 0.0);    g_signal_connect (G_OBJECT (adj2), "value_changed",                      G_CALLBACK (cb_digits_scale), NULL);    scale = gtk_hscale_new (GTK_ADJUSTMENT (adj2));    gtk_scale_set_digits (GTK_SCALE (scale), 0);    gtk_box_pack_start (GTK_BOX (box2), scale, TRUE, TRUE, 0);    gtk_widget_show (scale);    gtk_box_pack_start (GTK_BOX (box1), box2, TRUE, TRUE, 0);    gtk_widget_show (box2);      box2 = gtk_hbox_new (FALSE, 10);    gtk_container_set_border_width (GTK_CONTAINER (box2), 10);      /* And, one last HScale widget for adjusting the page size of the     * scrollbar. */    label = gtk_label_new ("Scrollbar Page Size:");    gtk_box_pack_start (GTK_BOX (box2), label, FALSE, FALSE, 0);    gtk_widget_show (label);    adj2 = gtk_adjustment_new (1.0, 1.0, 101.0, 1.0, 1.0, 0.0);    g_signal_connect (G_OBJECT (adj2), "value_changed",                      G_CALLBACK (cb_page_size), (gpointer) adj1);    scale = gtk_hscale_new (GTK_ADJUSTMENT (adj2));    gtk_scale_set_digits (GTK_SCALE (scale), 0);    gtk_box_pack_start (GTK_BOX (box2), scale, TRUE, TRUE, 0);    gtk_widget_show (scale);    gtk_box_pack_start (GTK_BOX (box1), box2, TRUE, TRUE, 0);    gtk_widget_show (box2);    separator = gtk_hseparator_new ();    gtk_box_pack_start (GTK_BOX (box1), separator, FALSE, TRUE, 0);    gtk_widget_show (separator);    box2 = gtk_vbox_new (FALSE, 10);    gtk_container_set_border_width (GTK_CONTAINER (box2), 10);    gtk_box_pack_start (GTK_BOX (box1), box2, FALSE, TRUE, 0);    gtk_widget_show (box2);    button = gtk_button_new_with_label ("Quit");    g_signal_connect_swapped (G_OBJECT (button), "clicked",                              G_CALLBACK (gtk_main_quit),                              NULL);    gtk_box_pack_start (GTK_BOX (box2), button, TRUE, TRUE, 0);    GTK_WIDGET_SET_FLAGS (button, GTK_CAN_DEFAULT);    gtk_widget_grab_default (button);    gtk_widget_show (button);    gtk_widget_show (window);}int main( int   argc,          char *argv[] ){    gtk_init (&argc, &argv);    create_range_controls ();    gtk_main ();    return 0;}