10.2. Arrows

The Arrow widget draws an arrowhead, facing in a number of possible directions and having a number of possible styles. It can be very useful when placed on a button in many applications. Like the Label widget, it emits no signals.

There are only two functions for manipulating an Arrow widget:

GtkWidget *gtk_arrow_new( GtkArrowType   arrow_type,
                          GtkShadowType  shadow_type );

void gtk_arrow_set( GtkArrow      *arrow,
                    GtkArrowType   arrow_type,
                    GtkShadowType  shadow_type );

The first creates a new arrow widget with the indicated type and appearance. The second allows these values to be altered retrospectively. The arrow_type argument may take one of the following values:

  GTK_ARROW_UP
  GTK_ARROW_DOWN
  GTK_ARROW_LEFT
  GTK_ARROW_RIGHT

These values obviously indicate the direction in which the arrow will point. The shadow_type argument may take one of these values:

  GTK_SHADOW_IN
  GTK_SHADOW_OUT (the default)
  GTK_SHADOW_ETCHED_IN
  GTK_SHADOW_ETCHED_OUT

Here's a brief example to illustrate their use.

#include <gtk/gtk.h>

/* Create an Arrow widget with the specified parameters
 * and pack it into a button */
static GtkWidget *create_arrow_button( GtkArrowType  arrow_type,
                                       GtkShadowType shadow_type )
{
  GtkWidget *button;
  GtkWidget *arrow;

  button = gtk_button_new ();
  arrow = gtk_arrow_new (arrow_type, shadow_type);

  gtk_container_add (GTK_CONTAINER (button), arrow);
  
  gtk_widget_show (button);
  gtk_widget_show (arrow);

  return button;
}

int main( int   argc,
          char *argv[] )
{
  /* GtkWidget is the storage type for widgets */
  GtkWidget *window;
  GtkWidget *button;
  GtkWidget *box;

  /* Initialize the toolkit */
  gtk_init (&argc, &argv);

  /* Create a new window */
  window = gtk_window_new (GTK_WINDOW_TOPLEVEL);

  gtk_window_set_title (GTK_WINDOW (window), "Arrow Buttons");

  /* It's a good idea to do this for all windows. */
  g_signal_connect (G_OBJECT (window), "destroy",
                    G_CALLBACK (gtk_main_quit), NULL);

  /* Sets the border width of the window. */
  gtk_container_set_border_width (GTK_CONTAINER (window), 10);

  /* Create a box to hold the arrows/buttons */
  box = gtk_hbox_new (FALSE, 0);
  gtk_container_set_border_width (GTK_CONTAINER (box), 2);
  gtk_container_add (GTK_CONTAINER (window), box);

  /* Pack and show all our widgets */
  gtk_widget_show (box);

  button = create_arrow_button (GTK_ARROW_UP, GTK_SHADOW_IN);
  gtk_box_pack_start (GTK_BOX (box), button, FALSE, FALSE, 3);

  button = create_arrow_button (GTK_ARROW_DOWN, GTK_SHADOW_OUT);
  gtk_box_pack_start (GTK_BOX (box), button, FALSE, FALSE, 3);
  
  button = create_arrow_button (GTK_ARROW_LEFT, GTK_SHADOW_ETCHED_IN);
  gtk_box_pack_start (GTK_BOX (box), button, FALSE, FALSE, 3);
  
  button = create_arrow_button (GTK_ARROW_RIGHT, GTK_SHADOW_ETCHED_OUT);
  gtk_box_pack_start (GTK_BOX (box), button, FALSE, FALSE, 3);
  
  gtk_widget_show (window);
  
  /* Rest in gtk_main and wait for the fun to begin! */
  gtk_main ();
  
  return 0;
}