gtk/demos/gtk-demo/colorsel.c

/* Color Selector
 *
 * GtkColorSelection lets the user choose a color. GtkColorSelectionDialog is
 * a prebuilt dialog containing a GtkColorSelection.
 *
 */

#include <gtk/gtk.h>

static GtkWidget *window = NULL;
static GtkWidget *da;
static GdkColor color;
static GtkWidget *frame;

static void
change_color_callback (GtkWidget *button,
                       gpointer   data)
{
  GtkWidget *dialog;
  GtkColorSelection *colorsel;
  gint response;
  
  dialog = gtk_color_selection_dialog_new ("Changing color");

  gtk_window_set_transient_for (GTK_WINDOW (dialog), GTK_WINDOW (window));
  
  colorsel = GTK_COLOR_SELECTION (GTK_COLOR_SELECTION_DIALOG (dialog)->colorsel);

  gtk_color_selection_set_previous_color (colorsel, &color);
  gtk_color_selection_set_current_color (colorsel, &color);
  gtk_color_selection_set_has_palette (colorsel, TRUE);
  
  response = gtk_dialog_run (GTK_DIALOG (dialog));

  if (response == GTK_RESPONSE_OK)
    {
      gtk_color_selection_get_current_color (colorsel,
                                             &color);
      
      gtk_widget_modify_bg (da, GTK_STATE_NORMAL, &color);
    }
  
  gtk_widget_destroy (dialog);
}

GtkWidget *
do_colorsel (void)
{
  GtkWidget *vbox;
  GtkWidget *button;
  GtkWidget *alignment;
  
  if (!window)
    {
      color.red = 0;
      color.blue = 65535;
      color.green = 0;
      
      window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
      gtk_window_set_title (GTK_WINDOW (window), "Color Selection");

      gtk_signal_connect (GTK_OBJECT (window), "destroy", GTK_SIGNAL_FUNC (gtk_widget_destroyed), &window);

      gtk_container_set_border_width (GTK_CONTAINER (window), 8);

      vbox = gtk_vbox_new (FALSE, 8);
      gtk_container_set_border_width (GTK_CONTAINER (vbox), 8);
      gtk_container_add (GTK_CONTAINER (window), vbox);

      /*
       * Create the color swatch area
       */
      
      
      frame = gtk_frame_new (NULL);
      gtk_frame_set_shadow_type (GTK_FRAME (frame), GTK_SHADOW_IN);
      gtk_box_pack_start (GTK_BOX (vbox), frame, TRUE, TRUE, 0);
      
      da = gtk_drawing_area_new ();
      /* set a minimum size */
      gtk_widget_set_usize (da, 200, 200);
      /* set the color */
      gtk_widget_modify_bg (da, GTK_STATE_NORMAL, &color);
      
      gtk_container_add (GTK_CONTAINER (frame), da);

      alignment = gtk_alignment_new (1.0, 0.5, 0.0, 0.0);
      
      button = gtk_button_new_with_mnemonic ("_Change the above color");
      gtk_container_add (GTK_CONTAINER (alignment), button);
      
      gtk_box_pack_start (GTK_BOX (vbox), alignment, FALSE, FALSE, 0);
      
      gtk_signal_connect (GTK_OBJECT (button), "clicked",
                          GTK_SIGNAL_FUNC (change_color_callback),
                          NULL);
    }

  if (!GTK_WIDGET_VISIBLE (window))
    {
      gtk_widget_show_all (window);
    }
  else
    {
      gtk_widget_destroy (window);
      window = NULL;
    }

  return window;
}