GTK: Minimize usage of gtk headers.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/2891006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@51898 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 66 insertions, 0 deletions

diff --git a/app/gtk_signal_registrar.h b/app/gtk_signal_registrar.h
new file mode 100644
index 0000000..3f14dbe
--- /dev/null
+++ b/app/gtk_signal_registrar.h
@@ -0,0 +1,66 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef APP_GTK_SIGNAL_REGISTRAR_H_
+#define APP_GTK_SIGNAL_REGISTRAR_H_
+
+#include <glib.h>
+#include <map>
+#include <vector>
+
+#include "base/basictypes.h"
+
+typedef void (*GCallback) (void);
+typedef struct _GObject GObject;
+typedef struct _GtkWidget GtkWidget;
+
+// A class that ensures that callbacks don't run on stale owner objects. Similar
+// in spirit to NotificationRegistrar. Use as follows:
+//
+//   class ChromeObject {
+//    public:
+//     ChromeObject() {
+//       ...
+//
+//       signals_.Connect(widget, "event", CallbackThunk, this);
+//     }
+//
+//     ...
+//
+//    private:
+//     GtkSignalRegistrar signals_;
+//   };
+//
+// When |signals_| goes down, it will disconnect the handlers connected via
+// Connect.
+class GtkSignalRegistrar {
+ public:
+  GtkSignalRegistrar();
+  ~GtkSignalRegistrar();
+
+  // Connect before the default handler. Returns the handler id.
+  glong Connect(gpointer instance, const gchar* detailed_signal,
+                GCallback signal_handler, gpointer data);
+  // Connect after the default handler. Returns the handler id.
+  glong ConnectAfter(gpointer instance, const gchar* detailed_signal,
+                     GCallback signal_handler, gpointer data);
+
+ private:
+  static void WeakNotifyThunk(gpointer data, GObject* where_the_object_was) {
+    reinterpret_cast<GtkSignalRegistrar*>(data)->WeakNotify(
+        where_the_object_was);
+  }
+  void WeakNotify(GObject* where_the_object_was);
+
+  glong ConnectInternal(gpointer instance, const gchar* detailed_signal,
+                        GCallback signal_handler, gpointer data, bool after);
+
+  typedef std::vector<glong> HandlerList;
+  typedef std::map<GObject*, HandlerList> HandlerMap;
+  HandlerMap handler_lists_;
+
+  DISALLOW_COPY_AND_ASSIGN(GtkSignalRegistrar);
+};
+
+#endif  // APP_GTK_SIGNAL_REGISTRAR_H_