gtk2/gtk/gtkcombo.c

/* gtkcombo - combo widget for gtk+
 * Copyright 1997 Paolo Molaro
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/*
 * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
 * file for a list of people on the GTK+ Team.  See the ChangeLog
 * files for a list of changes.  These files are distributed with
 * GTK+ at ftp://ftp.gtk.org/pub/gtk/. 
 */

/* Do NOT, I repeat, NOT, copy any of the code in this file.
 * The code here relies on all sorts of internal details of GTK+
 */

#include <string.h>

#include "gtkarrow.h"
#include "gtklabel.h"
#include "gtklist.h"
#include "gtkentry.h"
#include "gtkeventbox.h"
#include "gtkbutton.h"
#include "gtklistitem.h"
#include "gtkscrolledwindow.h"
#include "gtkmain.h"
#include "gtksignal.h"
#include "gtkwindow.h"
#include "gdk/gdkkeysyms.h"
#include "gtkcombo.h"
#include "gtkframe.h"
#include "gtkintl.h"

const gchar *gtk_combo_string_key = "gtk-combo-string-value";

#define COMBO_LIST_MAX_HEIGHT	(400)
#define	EMPTY_LIST_HEIGHT	(15)

enum {
  PROP_0,
  PROP_ENABLE_ARROW_KEYS,
  PROP_ENABLE_ARROWS_ALWAYS,
  PROP_CASE_SENSITIVE,
  PROP_ALLOW_EMPTY,
  PROP_VALUE_IN_LIST
};

static void         gtk_combo_class_init         (GtkComboClass    *klass);
static void         gtk_combo_init               (GtkCombo         *combo);
static void         gtk_combo_destroy            (GtkObject        *combo);
static GtkListItem *gtk_combo_find               (GtkCombo         *combo);
static gchar *      gtk_combo_func               (GtkListItem      *li);
static gint         gtk_combo_focus_idle         (GtkCombo         *combo);
static gint         gtk_combo_entry_focus_out    (GtkEntry         *entry,
						  GdkEventFocus    *event,
						  GtkCombo         *combo);
static void         gtk_combo_get_pos            (GtkCombo         *combo,
						  gint             *x,
						  gint             *y,
						  gint             *height,
						  gint             *width);
static void         gtk_combo_popup_list         (GtkCombo         *combo);
static void         gtk_combo_activate           (GtkWidget        *widget,
						  GtkCombo         *combo);
static gboolean     gtk_combo_popup_button_press (GtkWidget        *button,
						  GdkEventButton   *event,
						  GtkCombo         *combo);
static gboolean     gtk_combo_popup_button_leave (GtkWidget        *button,
						  GdkEventCrossing *event,
						  GtkCombo         *combo);
static void         gtk_combo_update_entry       (GtkList          *list,
						  GtkCombo         *combo);
static void         gtk_combo_update_list        (GtkEntry         *entry,
						  GtkCombo         *combo);
static gint         gtk_combo_button_press       (GtkWidget        *widget,
						  GdkEvent         *event,
						  GtkCombo         *combo);
static void         gtk_combo_button_event_after (GtkWidget        *widget,
						  GdkEvent         *event,
						  GtkCombo         *combo);
static gint         gtk_combo_list_enter         (GtkWidget        *widget,
						  GdkEventCrossing *event,
						  GtkCombo         *combo);
static gint         gtk_combo_list_key_press     (GtkWidget        *widget,
						  GdkEventKey      *event,
						  GtkCombo         *combo);
static gint         gtk_combo_entry_key_press    (GtkEntry         *widget,
						  GdkEventKey      *event,
						  GtkCombo         *combo);
static gint         gtk_combo_window_key_press   (GtkWidget        *window,
						  GdkEventKey      *event,
						  GtkCombo         *combo);
static void         gtk_combo_item_destroy       (GtkObject        *object);
static void         gtk_combo_size_allocate      (GtkWidget        *widget,
						  GtkAllocation   *allocation);
static void         gtk_combo_set_property       (GObject         *object,
						  guint            prop_id,
						  const GValue    *value,
						  GParamSpec      *pspec);
static void         gtk_combo_get_property       (GObject         *object,
						  guint            prop_id,
						  GValue          *value,
						  GParamSpec      *pspec);
static GtkHBoxClass *parent_class = NULL;

static void
gtk_combo_class_init (GtkComboClass * klass)
{
  GObjectClass *gobject_class;
  GtkObjectClass *oclass;
  GtkWidgetClass *widget_class;

  gobject_class = (GObjectClass *) klass;
  parent_class = gtk_type_class (GTK_TYPE_HBOX);
  oclass = (GtkObjectClass *) klass;
  widget_class = (GtkWidgetClass *) klass;

  gobject_class->set_property = gtk_combo_set_property; 
  gobject_class->get_property = gtk_combo_get_property; 

  g_object_class_install_property (gobject_class,
                                   PROP_ENABLE_ARROW_KEYS,
                                   g_param_spec_boolean ("enable_arrow_keys",
                                                         _("Enable arrow keys"),
                                                         _("Whether the arrow keys move through the list of items"),
                                                         TRUE,
                                                         G_PARAM_READABLE | G_PARAM_WRITABLE));
  g_object_class_install_property (gobject_class,
                                   PROP_ENABLE_ARROWS_ALWAYS,
                                   g_param_spec_boolean ("enable_arrows_always",
                                                         _("Always enable arrows"),
                                                         _("Whether the arrow keys work, even if the entry contents are not in the list"),
                                                         TRUE,
                                                         G_PARAM_READABLE | G_PARAM_WRITABLE));
  g_object_class_install_property (gobject_class,
                                   PROP_CASE_SENSITIVE,
                                   g_param_spec_boolean ("case_sensitive",
                                                         _("Case sensitive"),
                                                         _("Whether list item matching is case sensitive"),
                                                         FALSE,
                                                         G_PARAM_READABLE | G_PARAM_WRITABLE));

  g_object_class_install_property (gobject_class,
                                   PROP_ALLOW_EMPTY,
                                   g_param_spec_boolean ("allow_empty",
                                                         _("Allow empty"),
							 _("Whether an empty value may be entered in this field"),
                                                         TRUE,
                                                         G_PARAM_READABLE | G_PARAM_WRITABLE));

  g_object_class_install_property (gobject_class,
                                   PROP_VALUE_IN_LIST,
                                   g_param_spec_boolean ("value_in_list",
                                                         _("Value in list"),
                                                         _("Whether entered values must already be present in the list"),
                                                         FALSE,
                                                         G_PARAM_READABLE | G_PARAM_WRITABLE));
  
   
  oclass->destroy = gtk_combo_destroy;
  
  widget_class->size_allocate = gtk_combo_size_allocate;
}

static void
gtk_combo_destroy (GtkObject *object)
{
  GtkCombo *combo = GTK_COMBO (object);

  if (combo->popwin)
    {
      gtk_widget_destroy (combo->popwin);
      gtk_widget_unref (combo->popwin);
      combo->popwin = NULL;
    }

  GTK_OBJECT_CLASS (parent_class)->destroy (object);
}

static int
gtk_combo_entry_key_press (GtkEntry * entry, GdkEventKey * event, GtkCombo * combo)
{
  GList *li;

  /* completion */
  if ((event->keyval == GDK_Tab ||
       event->keyval == GDK_ISO_Left_Tab ||
       event->keyval == GDK_KP_Tab) &&
      (event->state & GDK_MOD1_MASK)) 
    {
      GtkEditable *editable = GTK_EDITABLE (entry);
    GCompletion * cmpl;
    gchar* prefix;
    gchar* nprefix = NULL;
    gint pos;

    if ( !GTK_LIST (combo->list)->children )
      return FALSE;
    
    gtk_signal_emit_stop_by_name (GTK_OBJECT (entry), "key_press_event");

    cmpl = g_completion_new ((GCompletionFunc)gtk_combo_func);
    g_completion_add_items (cmpl, GTK_LIST (combo->list)->children);

    pos = gtk_editable_get_position (editable);
    prefix = gtk_editable_get_chars (editable, 0, pos);

    g_completion_complete (cmpl, prefix, &nprefix);

    if (nprefix && strlen (nprefix) > strlen (prefix)) 
      {
    	gtk_editable_insert_text (editable, nprefix + pos, 
				  strlen (nprefix) - strlen (prefix), &pos);
	gtk_editable_set_position (editable, pos);
    }

    if (nprefix)
      g_free (nprefix);
    g_free (prefix);
    g_completion_free (cmpl);

    return TRUE;
  }

  if (!combo->use_arrows || !GTK_LIST (combo->list)->children)
    return FALSE;

  li = g_list_find (GTK_LIST (combo->list)->children, gtk_combo_find (combo));

  if ((event->keyval == GDK_Up)
      || (event->keyval == GDK_KP_Up)
      || ((event->state & GDK_MOD1_MASK) && ((event->keyval == 'p') || (event->keyval == 'P'))))
    {
      if (li)
	li = li->prev;
      if (!li && combo->use_arrows_always)
	{
	  li = g_list_last (GTK_LIST (combo->list)->children);
	}
      if (li)
	{
	  gtk_list_select_child (GTK_LIST (combo->list), GTK_WIDGET (li->data));
	  gtk_signal_emit_stop_by_name (GTK_OBJECT (entry), "key_press_event");
	  return TRUE;
	}
    }
  else if ((event->keyval == GDK_Down)
	   || (event->keyval == GDK_KP_Down)
	   || ((event->state & GDK_MOD1_MASK) && ((event->keyval == 'n') || (event->keyval == 'N'))))
    {
      if (li)
	li = li->next;
      if (!li && combo->use_arrows_always)
	{
	  li = GTK_LIST (combo->list)->children;
	}
      if (li)
	{
	  gtk_list_select_child (GTK_LIST (combo->list), GTK_WIDGET (li->data));
	  gtk_signal_emit_stop_by_name (GTK_OBJECT (entry), "key_press_event");
	  return TRUE;
	}
    }
  return FALSE;
}

static int
gtk_combo_window_key_press (GtkWidget   *window,
			    GdkEventKey *event,
			    GtkCombo    *combo)
{
  if (event->keyval == GDK_Return || event->keyval == GDK_KP_Enter)
    {
      if (GTK_WIDGET_VISIBLE (combo->popwin))
	{
	  gtk_widget_hide (combo->popwin);
	  
	  if (GTK_WIDGET_HAS_GRAB (combo->popwin))
	    {
	      gtk_grab_remove (combo->popwin);
	      gdk_pointer_ungrab (event->time);
	    }
	}

      gtk_signal_emit_stop_by_name (GTK_OBJECT (window), "key_press_event");

      return TRUE;
    }

  return FALSE;
}

static GtkListItem *
gtk_combo_find (GtkCombo * combo)
{
  const gchar *text;
  gchar *ltext;
  GList *clist;
  int (*string_compare) (const char *, const char *);

  if (combo->case_sensitive)
    string_compare = strcmp;
  else
    string_compare = g_strcasecmp;

  text = gtk_entry_get_text (GTK_ENTRY (combo->entry));
  clist = GTK_LIST (combo->list)->children;

  while (clist && clist->data)
    {
      ltext = gtk_combo_func (GTK_LIST_ITEM (clist->data));
      if (!ltext)
	continue;
      if (!(*string_compare) (ltext, text))
	return (GtkListItem *) clist->data;
      clist = clist->next;
    }

  return NULL;
}

static gchar *
gtk_combo_func (GtkListItem * li)
{
  GtkWidget *label;
  gchar *ltext = NULL;

  ltext = (gchar *) gtk_object_get_data (GTK_OBJECT (li), gtk_combo_string_key);
  if (!ltext)
    {
      label = GTK_BIN (li)->child;
      if (!label || !GTK_IS_LABEL (label))
	return NULL;
      gtk_label_get (GTK_LABEL (label), &ltext);
    }
  return ltext;
}

static gint
gtk_combo_focus_idle (GtkCombo * combo)
{
  if (combo)
    {
      GDK_THREADS_ENTER ();
      gtk_widget_grab_focus (combo->entry);
      GDK_THREADS_LEAVE ();
    }
  return FALSE;
}

static gint
gtk_combo_entry_focus_out (GtkEntry * entry, GdkEventFocus * event, GtkCombo * combo)
{

  if (combo->value_in_list && !gtk_combo_find (combo))
    {
      /* gdk_beep(); *//* this can be annoying */
      if (combo->ok_if_empty && !strcmp (gtk_entry_get_text (entry), ""))
	return FALSE;
#ifdef TEST
      printf ("INVALID ENTRY: `%s'\n", gtk_entry_get_text (entry));
#endif
      gtk_grab_add (GTK_WIDGET (combo));
      /* this is needed because if we call gtk_widget_grab_focus() 
         it isn't guaranteed it's the *last* call before the main-loop,
         so the focus can be lost anyway...
         the signal_emit_stop doesn't seem to work either...
       */
      gtk_idle_add ((GtkFunction) gtk_combo_focus_idle, combo);
      /*gtk_signal_emit_stop_by_name (GTK_OBJECT (entry), "focus_out_event"); */
      return TRUE;
    }
  return FALSE;
}

static void
gtk_combo_get_pos (GtkCombo * combo, gint * x, gint * y, gint * height, gint * width)
{
  GtkBin *popwin;
  GtkWidget *widget;
  GtkScrolledWindow *popup;
  
  gint real_height;
  GtkRequisition list_requisition;
  gboolean show_hscroll = FALSE;
  gboolean show_vscroll = FALSE;
  gint avail_height;
  gint min_height;
  gint alloc_width;
  gint work_height;
  gint old_height;
  gint old_width;
  
  widget = GTK_WIDGET (combo);
  popup  = GTK_SCROLLED_WINDOW (combo->popup);
  popwin = GTK_BIN (combo->popwin);
  
  gdk_window_get_origin (combo->entry->window, x, y);
  real_height = MIN (combo->entry->requisition.height, 
		     combo->entry->allocation.height);
  *y += real_height;
  avail_height = gdk_screen_height () - *y;
  
  gtk_widget_size_request (combo->list, &list_requisition);
  min_height = MIN (list_requisition.height, 
		    popup->vscrollbar->requisition.height);
  if (!GTK_LIST (combo->list)->children)
    list_requisition.height += EMPTY_LIST_HEIGHT;
  
  alloc_width = (widget->allocation.width -
		 2 * popwin->child->style->xthickness -
		 2 * GTK_CONTAINER (popwin->child)->border_width -
		 2 * GTK_CONTAINER (combo->popup)->border_width -
		 2 * GTK_CONTAINER (GTK_BIN (popup)->child)->border_width - 
		 2 * GTK_BIN (popup)->child->style->xthickness);
  
  work_height = (2 * popwin->child->style->ythickness +
		 2 * GTK_CONTAINER (popwin->child)->border_width +
		 2 * GTK_CONTAINER (combo->popup)->border_width +
		 2 * GTK_CONTAINER (GTK_BIN (popup)->child)->border_width +
		 2 * GTK_BIN (popup)->child->style->xthickness);
  
  do 
    {
      old_width = alloc_width;
      old_height = work_height;
      
      if (!show_hscroll &&
	  alloc_width < list_requisition.width)
	{
	  work_height += (popup->hscrollbar->requisition.height +
			  GTK_SCROLLED_WINDOW_GET_CLASS (combo->popup)->scrollbar_spacing);
	  show_hscroll = TRUE;
	}
      if (!show_vscroll && 
	  work_height + list_requisition.height > avail_height)
	{
	  if (work_height + min_height > avail_height && 
	      *y - real_height > avail_height)
	    {
	      *y -= (work_height + list_requisition.height + real_height);
	      break;
	    }
	  alloc_width -= (popup->vscrollbar->requisition.width +
			  GTK_SCROLLED_WINDOW_GET_CLASS (combo->popup)->scrollbar_spacing);
	  show_vscroll = TRUE;
	}
    } while (old_width != alloc_width || old_height != work_height);
  
  *width = widget->allocation.width;
  if (show_vscroll)
    *height = avail_height;
  else
    *height = work_height + list_requisition.height;
  
  if (*x < 0)
    *x = 0;
}

static void
gtk_combo_popup_list (GtkCombo * combo)
{
  gint height, width, x, y;
  gint old_width, old_height;

  old_width = combo->popwin->allocation.width;
  old_height  = combo->popwin->allocation.height;

  gtk_combo_get_pos (combo, &x, &y, &height, &width);

  /* workaround for gtk_scrolled_window_size_allocate bug */
  if (old_width != width || old_height != height)
    {
      gtk_widget_hide (GTK_SCROLLED_WINDOW (combo->popup)->hscrollbar);
      gtk_widget_hide (GTK_SCROLLED_WINDOW (combo->popup)->vscrollbar);
    }

  gtk_window_move (GTK_WINDOW (combo->popwin), x, y);
  gtk_widget_set_usize (combo->popwin, width, height);
  gtk_widget_show (combo->popwin);

  gtk_widget_grab_focus (combo->popwin);
}

static void
gtk_combo_popdown_list (GtkCombo *combo)
{
  combo->current_button = 0;
      
  if (GTK_BUTTON (combo->button)->in_button)
    {
      GTK_BUTTON (combo->button)->in_button = FALSE;
      gtk_button_released (GTK_BUTTON (combo->button));
    }

  if (GTK_WIDGET_HAS_GRAB (combo->popwin))
    {
      gtk_grab_remove (combo->popwin);
      gdk_pointer_ungrab (GDK_CURRENT_TIME);
    }
  
  gtk_widget_hide (combo->popwin);
}

static void        
gtk_combo_activate (GtkWidget        *widget,
		    GtkCombo         *combo)
{
  gtk_combo_popup_list (combo);

  if (!GTK_WIDGET_HAS_FOCUS (combo->entry))
    gtk_widget_grab_focus (combo->entry);

  gtk_grab_add (combo->popwin);
  gdk_pointer_grab (combo->popwin->window, TRUE,
		    GDK_BUTTON_PRESS_MASK | 
		    GDK_BUTTON_RELEASE_MASK |
		    GDK_POINTER_MOTION_MASK, 
		    NULL, NULL, GDK_CURRENT_TIME);
}

static gboolean
gtk_combo_popup_button_press (GtkWidget        *button,
			      GdkEventButton   *event,
			      GtkCombo         *combo)
{
  if (!GTK_WIDGET_HAS_FOCUS (combo->entry))
    gtk_widget_grab_focus (combo->entry);

  if (event->button != 1)
    return FALSE;

  combo->current_button = event->button;

  gtk_combo_popup_list (combo);
  gtk_button_pressed (GTK_BUTTON (button));

  gtk_grab_add (combo->popwin);
  gdk_pointer_grab (combo->popwin->window, TRUE,
		    GDK_BUTTON_PRESS_MASK | 
		    GDK_BUTTON_RELEASE_MASK |
		    GDK_POINTER_MOTION_MASK, 
		    NULL, NULL, GDK_CURRENT_TIME);

  GTK_LIST (combo->list)->drag_selection = TRUE;
  gtk_grab_add (combo->list);

  return TRUE;
}

static gboolean
gtk_combo_popup_button_leave (GtkWidget        *button,
			      GdkEventCrossing *event,
			      GtkCombo         *combo)
{
  /* The idea here is that we want to keep the button down if the
   * popup is popped up.
   */
  return combo->current_button != 0;
}

static void
gtk_combo_update_entry (GtkList * list, GtkCombo * combo)
{
  char *text;

  gtk_grab_remove (GTK_WIDGET (combo));
  gtk_signal_handler_block (GTK_OBJECT (list), combo->list_change_id);
  if (list->selection)
    {
      text = gtk_combo_func (GTK_LIST_ITEM (list->selection->data));
      if (!text)
	text = "";
      gtk_entry_set_text (GTK_ENTRY (combo->entry), text);
    }
  gtk_signal_handler_unblock (GTK_OBJECT (list), combo->list_change_id);
}

static void
gtk_combo_update_list (GtkEntry * entry, GtkCombo * combo)
{
  GtkList *list = GTK_LIST (combo->list);
  GList *slist = list->selection;
  GtkListItem *li;

  gtk_grab_remove (GTK_WIDGET (combo));

  gtk_signal_handler_block (GTK_OBJECT (entry), combo->entry_change_id);
  if (slist && slist->data)
    gtk_list_unselect_child (list, GTK_WIDGET (slist->data));
  li = gtk_combo_find (combo);
  if (li)
    gtk_list_select_child (list, GTK_WIDGET (li));
  gtk_signal_handler_unblock (GTK_OBJECT (entry), combo->entry_change_id);
}

static gint
gtk_combo_button_press (GtkWidget * widget, GdkEvent * event, GtkCombo * combo)
{
  GtkWidget *child;

  child = gtk_get_event_widget (event);

  /* We don't ask for button press events on the grab widget, so
   *  if an event is reported directly to the grab widget, it must
   *  be on a window outside the application (and thus we remove
   *  the popup window). Otherwise, we check if the widget is a child
   *  of the grab widget, and only remove the popup window if it
   *  is not.
   */
  if (child != widget)
    {
      while (child)
	{
	  if (child == widget)
	    return FALSE;
	  child = child->parent;
	}
    }

  gtk_combo_popdown_list (combo);

  return TRUE;
}

static void
gtk_combo_button_event_after (GtkWidget *widget,
			      GdkEvent  *event,
			      GtkCombo  *combo)
{
  GtkWidget *child;

  if (event->type != GDK_BUTTON_RELEASE)
    return;
  
  if ((combo->current_button != 0) && (event->button.button == 1))
    {
      /* This was the initial button press */

      combo->current_button = 0;

      /* Check to see if we released inside the button */
      child = gtk_get_event_widget ((GdkEvent*) event);

      while (child && child != (combo->button))
	child = child->parent;

      if (child == combo->button)
	{
	  gtk_grab_add (combo->popwin);
	  gdk_pointer_grab (combo->popwin->window, TRUE,
			    GDK_BUTTON_PRESS_MASK | 
			    GDK_BUTTON_RELEASE_MASK |
			    GDK_POINTER_MOTION_MASK, 
			    NULL, NULL, GDK_CURRENT_TIME);
	  return;
	}
    }

  gtk_combo_popdown_list (combo);
}

static gint         
gtk_combo_list_enter (GtkWidget        *widget,
		      GdkEventCrossing *event,
		      GtkCombo         *combo)
{
  GtkWidget *event_widget;

  event_widget = gtk_get_event_widget ((GdkEvent*) event);
  
  if ((event_widget == combo->list) &&
      (combo->current_button != 0) && 
      (!GTK_WIDGET_HAS_GRAB (combo->list)))
    {
      GdkEvent tmp_event;
      gint x, y;
      GdkModifierType mask;

      gtk_grab_remove (combo->popwin);

      /* Transfer the grab over to the list by synthesizing
       * a button press event
       */
      gdk_window_get_pointer (combo->list->window, &x, &y, &mask);

      tmp_event.button.type = GDK_BUTTON_PRESS;
      tmp_event.button.window = combo->list->window;
      tmp_event.button.send_event = TRUE;
      tmp_event.button.time = GDK_CURRENT_TIME; /* bad */
      tmp_event.button.x = x;
      tmp_event.button.y = y;
      /* We leave all the XInput fields unfilled here, in the expectation
       * that GtkList doesn't care.
       */
      tmp_event.button.button = combo->current_button;
      tmp_event.button.state = mask;

      gtk_widget_event (combo->list, &tmp_event);
    }

  return FALSE;
}

static int
gtk_combo_list_key_press (GtkWidget * widget, GdkEventKey * event, GtkCombo * combo)
{
  if (event->keyval == GDK_Escape)
    {
      if (GTK_WIDGET_HAS_GRAB (combo->list))
	gtk_list_end_drag_selection (GTK_LIST (combo->list));

      gtk_combo_popdown_list (combo);
      
      return TRUE;
    }
  return FALSE;
}

static void
gtk_combo_init (GtkCombo * combo)
{
  GtkWidget *arrow;
  GtkWidget *frame;
  GtkWidget *event_box;
  GdkCursor *cursor;

  combo->case_sensitive = FALSE;
  combo->value_in_list = FALSE;
  combo->ok_if_empty = TRUE;
  combo->use_arrows = TRUE;
  combo->use_arrows_always = FALSE;
  combo->entry = gtk_entry_new ();
  combo->button = gtk_button_new ();
  combo->current_button = 0;
  arrow = gtk_arrow_new (GTK_ARROW_DOWN, GTK_SHADOW_OUT);
  gtk_widget_show (arrow);
  gtk_container_add (GTK_CONTAINER (combo->button), arrow);
  gtk_box_pack_start (GTK_BOX (combo), combo->entry, TRUE, TRUE, 0);
  gtk_box_pack_end (GTK_BOX (combo), combo->button, FALSE, FALSE, 0);
  GTK_WIDGET_UNSET_FLAGS (combo->button, GTK_CAN_FOCUS);
  gtk_widget_show (combo->entry);
  gtk_widget_show (combo->button);
  combo->entry_change_id = gtk_signal_connect (GTK_OBJECT (combo->entry), "changed",
			      (GtkSignalFunc) gtk_combo_update_list, combo);
  gtk_signal_connect (GTK_OBJECT (combo->entry), "key_press_event",
		      (GtkSignalFunc) gtk_combo_entry_key_press, combo);
  gtk_signal_connect_after (GTK_OBJECT (combo->entry), "focus_out_event",
			    (GtkSignalFunc) gtk_combo_entry_focus_out, combo);
  combo->activate_id = gtk_signal_connect (GTK_OBJECT (combo->entry), "activate",
		      (GtkSignalFunc) gtk_combo_activate, combo);
  gtk_signal_connect (GTK_OBJECT (combo->button), "button_press_event",
		      (GtkSignalFunc) gtk_combo_popup_button_press, combo);
  gtk_signal_connect (GTK_OBJECT (combo->button), "leave_notify_event",
		      (GtkSignalFunc) gtk_combo_popup_button_leave, combo);

  combo->popwin = gtk_window_new (GTK_WINDOW_POPUP);
  gtk_widget_ref (combo->popwin);
  gtk_window_set_resizable (GTK_WINDOW (combo->popwin), FALSE);

  gtk_signal_connect (GTK_OBJECT (combo->popwin), "key_press_event",
		      GTK_SIGNAL_FUNC (gtk_combo_window_key_press), combo);
  
  gtk_widget_set_events (combo->popwin, GDK_KEY_PRESS_MASK);

  event_box = gtk_event_box_new ();
  gtk_container_add (GTK_CONTAINER (combo->popwin), event_box);
  gtk_widget_show (event_box);

  gtk_widget_realize (event_box);
  cursor = gdk_cursor_new (GDK_TOP_LEFT_ARROW);
  gdk_window_set_cursor (event_box->window, cursor);
  gdk_cursor_destroy (cursor);

  frame = gtk_frame_new (NULL);
  gtk_container_add (GTK_CONTAINER (event_box), frame);
  gtk_frame_set_shadow_type (GTK_FRAME (frame), GTK_SHADOW_OUT);
  gtk_widget_show (frame);

  combo->popup = gtk_scrolled_window_new (NULL, NULL);
  gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (combo->popup),
				  GTK_POLICY_AUTOMATIC, GTK_POLICY_AUTOMATIC);
  GTK_WIDGET_UNSET_FLAGS (GTK_SCROLLED_WINDOW (combo->popup)->hscrollbar, GTK_CAN_FOCUS);
  GTK_WIDGET_UNSET_FLAGS (GTK_SCROLLED_WINDOW (combo->popup)->vscrollbar, GTK_CAN_FOCUS);
  gtk_container_add (GTK_CONTAINER (frame), combo->popup);
  gtk_widget_show (combo->popup);

  combo->list = gtk_list_new ();
  /* We'll use enter notify events to figure out when to transfer
   * the grab to the list
   */
  gtk_widget_set_events (combo->list, GDK_ENTER_NOTIFY_MASK);

  gtk_list_set_selection_mode (GTK_LIST(combo->list), GTK_SELECTION_BROWSE);
  gtk_scrolled_window_add_with_viewport (GTK_SCROLLED_WINDOW (combo->popup), combo->list);
  gtk_container_set_focus_vadjustment (GTK_CONTAINER (combo->list),
				       gtk_scrolled_window_get_vadjustment (GTK_SCROLLED_WINDOW (combo->popup)));
  gtk_container_set_focus_hadjustment (GTK_CONTAINER (combo->list),
				       gtk_scrolled_window_get_hadjustment (GTK_SCROLLED_WINDOW (combo->popup)));
  gtk_widget_show (combo->list);

  combo->list_change_id = gtk_signal_connect (GTK_OBJECT (combo->list), "selection_changed",
			     (GtkSignalFunc) gtk_combo_update_entry, combo);
  gtk_signal_connect (GTK_OBJECT (combo->popwin), "key_press_event",
		      (GtkSignalFunc) gtk_combo_list_key_press, combo);
  gtk_signal_connect (GTK_OBJECT (combo->popwin), "button_press_event",
		      GTK_SIGNAL_FUNC (gtk_combo_button_press), combo);

  gtk_signal_connect (GTK_OBJECT (combo->list), "event_after",
		      (GtkSignalFunc) gtk_combo_button_event_after, combo);
  /* We connect here on the button, because we'll have a grab on it
   * when the event occurs. But we are actually interested in enters
   * for the combo->list.
   */
  gtk_signal_connect (GTK_OBJECT (combo->button), "enter_notify_event",
		      GTK_SIGNAL_FUNC (gtk_combo_list_enter), combo);
}

GtkType
gtk_combo_get_type (void)
{
  static GtkType combo_type = 0;

  if (!combo_type)
    {
      static const GtkTypeInfo combo_info =
      {
	"GtkCombo",
	sizeof (GtkCombo),
	sizeof (GtkComboClass),
	(GtkClassInitFunc) gtk_combo_class_init,
	(GtkObjectInitFunc) gtk_combo_init,
	/* reserved_1 */ NULL,
	/* reserved_2 */ NULL,
        (GtkClassInitFunc) NULL,
      };
      combo_type = gtk_type_unique (GTK_TYPE_HBOX, &combo_info);
    }
  return combo_type;
}

GtkWidget*
gtk_combo_new (void)
{
  return GTK_WIDGET (gtk_type_new (GTK_TYPE_COMBO));
}

void
gtk_combo_set_value_in_list (GtkCombo * combo, gboolean val, gboolean ok_if_empty)
{
  g_return_if_fail (GTK_IS_COMBO (combo));
  val = val != FALSE;
  ok_if_empty = ok_if_empty != FALSE;

  g_object_freeze_notify (G_OBJECT (combo));
  if (combo->value_in_list != val)
    {
       combo->value_in_list = val;
  g_object_notify (G_OBJECT (combo), "value_in_list");
    }
  if (combo->ok_if_empty != ok_if_empty)
    {
       combo->ok_if_empty = ok_if_empty;
  g_object_notify (G_OBJECT (combo), "allow_empty");
    }
  g_object_thaw_notify (G_OBJECT (combo));
}

void
gtk_combo_set_case_sensitive (GtkCombo * combo, gboolean val)
{
  g_return_if_fail (GTK_IS_COMBO (combo));
  val = val != FALSE;

  if (combo->case_sensitive != val) 
    {
  combo->case_sensitive = val;
  g_object_notify (G_OBJECT (combo), "case_sensitive");
    }
}

void
gtk_combo_set_use_arrows (GtkCombo * combo, gboolean val)
{
  g_return_if_fail (GTK_IS_COMBO (combo));
  val = val != FALSE;

  if (combo->use_arrows != val) 
    {
  combo->use_arrows = val;
  g_object_notify (G_OBJECT (combo), "enable_arrow_keys");
    }
}

void
gtk_combo_set_use_arrows_always (GtkCombo * combo, gboolean val)
{
  g_return_if_fail (GTK_IS_COMBO (combo));
  val = val != FALSE;

  if (combo->use_arrows_always != val) 
    {
       g_object_freeze_notify (G_OBJECT (combo));
  combo->use_arrows_always = val;
       g_object_notify (G_OBJECT (combo), "enable_arrows_always");

       if (combo->use_arrows != TRUE) 
         {
  combo->use_arrows = TRUE;
  g_object_notify (G_OBJECT (combo), "enable_arrow_keys");
         }
  g_object_thaw_notify (G_OBJECT (combo));
    }
}

void
gtk_combo_set_popdown_strings (GtkCombo * combo, GList * strings)
{
  GList *list;
  GtkWidget *li;

  g_return_if_fail (GTK_IS_COMBO (combo));
  g_return_if_fail (strings != NULL);

  gtk_list_clear_items (GTK_LIST (combo->list), 0, -1);
  list = strings;
  while (list)
    {
      li = gtk_list_item_new_with_label ((gchar *) list->data);
      gtk_widget_show (li);
      gtk_container_add (GTK_CONTAINER (combo->list), li);
      list = list->next;
    }
}

static void
gtk_combo_item_destroy (GtkObject * object)
{
  gchar *key;

  key = gtk_object_get_data (object, gtk_combo_string_key);
  if (key)
    {
      gtk_object_remove_data (object, gtk_combo_string_key);
      g_free (key);
    }
}

void
gtk_combo_set_item_string (GtkCombo * combo, GtkItem * item, const gchar * item_value)
{
  gchar *val;
  gint connected = 0;

  g_return_if_fail (GTK_IS_COMBO (combo));
  g_return_if_fail (item != NULL);

  val = gtk_object_get_data (GTK_OBJECT (item), gtk_combo_string_key);
  if (val) 
    {
      g_free (val);
      connected = 1;
    }
  if (item_value)
    {
      val = g_strdup (item_value);
      gtk_object_set_data (GTK_OBJECT (item), gtk_combo_string_key, val);
      if (!connected)
        gtk_signal_connect (GTK_OBJECT (item), "destroy",
			  (GtkSignalFunc) gtk_combo_item_destroy, val);
    }
  else 
    {
      gtk_object_set_data (GTK_OBJECT (item), gtk_combo_string_key, NULL);
      if (connected)
	gtk_signal_disconnect_by_data(GTK_OBJECT (item), val);
    }
}

static void
gtk_combo_size_allocate (GtkWidget     *widget,
			 GtkAllocation *allocation)
{
  GtkCombo *combo;

  g_return_if_fail (GTK_IS_COMBO (widget));
  g_return_if_fail (allocation != NULL);

  GTK_WIDGET_CLASS (parent_class)->size_allocate (widget, allocation);
  
  combo = GTK_COMBO (widget);

  if (combo->entry->allocation.height > combo->entry->requisition.height)
    {
      GtkAllocation button_allocation;

      button_allocation = combo->button->allocation;
      button_allocation.height = combo->entry->requisition.height;
      button_allocation.y = combo->entry->allocation.y + 
	(combo->entry->allocation.height - combo->entry->requisition.height) 
	/ 2;
      gtk_widget_size_allocate (combo->button, &button_allocation);
    }
}

void
gtk_combo_disable_activate (GtkCombo* combo)
{
  g_return_if_fail (GTK_IS_COMBO (combo));

  if ( combo->activate_id ) {
    gtk_signal_disconnect (GTK_OBJECT(combo->entry), combo->activate_id);
    combo->activate_id = 0;
  }
}

static void
gtk_combo_set_property (GObject         *object,
			guint            prop_id,
			const GValue    *value,
			GParamSpec      *pspec)
{
  GtkCombo *combo = GTK_COMBO (object);
  
  switch (prop_id)
    {
    case PROP_ENABLE_ARROW_KEYS:
      gtk_combo_set_use_arrows (combo, g_value_get_boolean (value));
      break;
    case PROP_ENABLE_ARROWS_ALWAYS:
      gtk_combo_set_use_arrows_always (combo, g_value_get_boolean (value));
      break;
    case PROP_CASE_SENSITIVE:
      gtk_combo_set_case_sensitive (combo, g_value_get_boolean (value));
      break;
    case PROP_ALLOW_EMPTY:
      combo->ok_if_empty = g_value_get_boolean (value);
      break;
    case PROP_VALUE_IN_LIST:
      combo->value_in_list = g_value_get_boolean (value);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
    }
  
}

static void
gtk_combo_get_property (GObject         *object,
			guint            prop_id,
			GValue          *value,
			GParamSpec      *pspec)
{
  GtkCombo *combo = GTK_COMBO (object);
  
  switch (prop_id)
    {
    case PROP_ENABLE_ARROW_KEYS:
      g_value_set_boolean (value, combo->use_arrows);
      break;
    case PROP_ENABLE_ARROWS_ALWAYS:
      g_value_set_boolean (value, combo->use_arrows_always);
      break;
    case PROP_CASE_SENSITIVE:
      g_value_set_boolean (value, combo->case_sensitive);
      break;
    case PROP_ALLOW_EMPTY:
      g_value_set_boolean (value, combo->ok_if_empty);
      break;
    case PROP_VALUE_IN_LIST:
      g_value_set_boolean (value, combo->value_in_list);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
    }
   
}