gtkcombo.c

gtk是linux一款强大的夸平台的图形化开发工具

/* 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 Library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library 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 1997-1999.  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/. 
 */

#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"

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

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

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 void         gtk_combo_popup_button_press (GtkWidget        *button,
						  GdkEventButton   *event,
						  GtkCombo         *combo);
static void         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 gint         gtk_combo_button_release  (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 void         gtk_combo_item_destroy    (GtkObject     *object);
static void         gtk_combo_size_allocate   (GtkWidget     *widget,
					       GtkAllocation *allocation);

static GtkHBoxClass *parent_class = NULL;

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

  parent_class = gtk_type_class (gtk_hbox_get_type ());
  oclass = (GtkObjectClass *) klass;
  widget_class = (GtkWidgetClass *) klass;

  oclass->destroy = gtk_combo_destroy;
  
  widget_class->size_allocate = gtk_combo_size_allocate;
}

static void
gtk_combo_destroy (GtkObject * combo)
{
  gtk_widget_destroy (GTK_COMBO (combo)->popwin);
  gtk_widget_unref (GTK_COMBO (combo)->popwin);

  if (GTK_OBJECT_CLASS (parent_class)->destroy)
    (*GTK_OBJECT_CLASS (parent_class)->destroy) (combo);
}

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

  /* completion */
  if ((event->keyval == GDK_Tab) && (event->state & GDK_MOD1_MASK)) 
    {
    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 (entry)->current_pos;
    prefix = gtk_editable_get_chars (GTK_EDITABLE (entry), 0, pos);

    g_completion_complete(cmpl, prefix, &nprefix);

    if (nprefix && strlen (nprefix) > strlen (prefix)) 
      {
    	gtk_editable_insert_text (GTK_EDITABLE (entry), nprefix + pos, 
				 strlen (nprefix) - strlen (prefix), &pos);
    	GTK_EDITABLE (entry)->current_pos = 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 GtkListItem *
gtk_combo_find (GtkCombo * combo)
{
  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->klass->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->klass->xthickness);
  
  work_height = (2 * popwin->child->style->klass->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->klass->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_CLASS 
	    (GTK_OBJECT (combo->popup)->klass)->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_CLASS 
	    (GTK_OBJECT (combo->popup)->klass)->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_widget_set_uposition (combo->popwin, x, y);
  gtk_widget_set_usize (combo->popwin, width, height);
  gtk_widget_realize (combo->popwin);
  gdk_window_resize (combo->popwin->window, width, height);
  gtk_widget_show (combo->popwin);

  gtk_widget_grab_focus (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 void        
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 (!combo->current_button && (event->button == 1))
    gtk_combo_popup_list (combo);

  combo->current_button = event->button;
  
  GTK_LIST (combo->list)->drag_selection = TRUE;
  gdk_pointer_grab (combo->list->window, TRUE,
		    GDK_POINTER_MOTION_HINT_MASK |
		    GDK_BUTTON1_MOTION_MASK |
		    GDK_BUTTON_RELEASE_MASK,
		    NULL, NULL, event->time);
  gtk_grab_add (combo->list);
}

static void         
gtk_combo_popup_button_leave (GtkWidget        *button,
			      GdkEventCrossing *event,
			      GtkCombo         *combo)
{
  if (combo->current_button)
    gtk_signal_emit_stop_by_name (GTK_OBJECT (button), "leave_notify_event");
}


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

  gtk_grab_remove (GTK_WIDGET (combo));