libnautilus-private/nautilus-clipboard-monitor.c

   1 /* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-
   2
   3    nautilus-clipboard-monitor.c: catch clipboard changes.
   4
   5    Copyright (C) 2004 Red Hat, Inc.
   6
   7    This program is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU General Public License as
   9    published by the Free Software Foundation; either version 2 of the
  10    License, or (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public
  18    License along with this program; if not, write to the
  19    Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.
  21
  22    Author: Alexander Larsson <alexl@redhat.com>
  23 */
  24
  25 #include <config.h>
  26 #include "nautilus-clipboard-monitor.h"
  27
  28 #include <eel/eel-debug.h>
  29 #include <eel/eel-gtk-macros.h>
  30 #include <eel/eel-glib-extensions.h>
  31 #include <eel/eel-glib-extensions.h>
  32 #include <gtk/gtkclipboard.h>
  33
  34 /* X11 has a weakness when it comes to clipboard handling,
  35  * there is no way to get told when the owner of the clipboard
  36  * changes. This is often needed, for instance to set the
  37  * sensitivity of the paste menu item. We work around this
  38  * internally in an app by telling the clipboard monitor when
  39  * we changed the clipboard. Unfortunately this doesn't give
  40  * us perfect results, we still don't catch changes made by
  41  * other clients
  42  *
  43  * This is fixed with the XFIXES extensions, which recent versions
  44  * of Gtk+ supports as the owner_change signal on GtkClipboard. We
  45  * use this now, but keep the old code since not all X servers support
  46  * XFIXES.
  47  */
  48
  49 enum {
  50         CLIPBOARD_CHANGED,
  51         LAST_SIGNAL
  52 };
  53
  54 static guint signals[LAST_SIGNAL];
  55
  56 static void nautilus_clipboard_monitor_init       (gpointer              object,
  57                                                    gpointer              klass);
  58 static void nautilus_clipboard_monitor_class_init (gpointer              klass);
  59
  60 EEL_CLASS_BOILERPLATE (NautilusClipboardMonitor,
  61                        nautilus_clipboard_monitor,
  62                        G_TYPE_OBJECT)
  63
  64 static NautilusClipboardMonitor *clipboard_monitor = NULL;
  65
  66 static void
  67 destroy_clipboard_monitor (void)
  68 {
  69         if (clipboard_monitor != NULL) {
  70                 g_object_unref (clipboard_monitor);
  71         }
  72 }
  73
  74 NautilusClipboardMonitor *
  75 nautilus_clipboard_monitor_get (void)
  76 {
  77         GtkClipboard *clipboard;
  78
  79         if (clipboard_monitor == NULL) {
  80                 clipboard_monitor = NAUTILUS_CLIPBOARD_MONITOR (g_object_new (NAUTILUS_TYPE_CLIPBOARD_MONITOR, NULL));
  81                 eel_debug_call_at_shutdown (destroy_clipboard_monitor);
  82
  83                 clipboard = gtk_clipboard_get (GDK_SELECTION_CLIPBOARD);
  84                 g_signal_connect (clipboard, "owner_change",
  85                                   G_CALLBACK (nautilus_clipboard_monitor_emit_changed), NULL);
  86         }
  87         return clipboard_monitor;
  88 }
  89
  90 void
  91 nautilus_clipboard_monitor_emit_changed (void)
  92 {
  93         NautilusClipboardMonitor *monitor;
  94
  95         monitor = nautilus_clipboard_monitor_get ();
  96
  97         g_signal_emit (monitor, signals[CLIPBOARD_CHANGED], 0);
  98 }
  99
 100 static void
 101 nautilus_clipboard_monitor_init (gpointer object, gpointer klass)
 102 {
 103         NautilusClipboardMonitor *monitor;
 104
 105         monitor = NAUTILUS_CLIPBOARD_MONITOR (object);
 106 }
 107
 108 static void
 109 clipboard_monitor_finalize (GObject *object)
 110 {
 111         NautilusClipboardMonitor *monitor;
 112
 113         monitor = NAUTILUS_CLIPBOARD_MONITOR (object);
 114
 115         EEL_CALL_PARENT (G_OBJECT_CLASS, finalize, (object));
 116 }
 117
 118 static void
 119 nautilus_clipboard_monitor_class_init (gpointer klass)
 120 {
 121         GObjectClass *object_class;
 122
 123         object_class = G_OBJECT_CLASS (klass);
 124
 125         object_class->finalize = clipboard_monitor_finalize;
 126
 127         signals[CLIPBOARD_CHANGED] =
 128                 g_signal_new ("clipboard_changed",
 129                               G_TYPE_FROM_CLASS (klass),
 130                               G_SIGNAL_RUN_LAST,
 131                               G_STRUCT_OFFSET (NautilusClipboardMonitorClass, clipboard_changed),
 132                               NULL, NULL,
 133                               g_cclosure_marshal_VOID__VOID,
 134                               G_TYPE_NONE, 0);
 135
 136 }
 137