GTK: make more use of gtk_signal convenience macros/signal registrar.

chrome/browser/gtk/hover_controller_gtk.cc

 // 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.
 
 #include "chrome/browser/gtk/hover_controller_gtk.h"
 
 #include "base/message_loop.h"
 #include "chrome/browser/gtk/gtk_chrome_button.h"
 
 static const gchar* kHoverControllerGtkKey = "__HOVER_CONTROLLER_GTK__";
 
 HoverControllerGtk::HoverControllerGtk(GtkWidget* button)
     : throb_animation_(this),
       hover_animation_(this),
       button_(button) {
   g_object_ref(button_);
   gtk_chrome_button_set_hover_state(GTK_CHROME_BUTTON(button_), 0);
 
-  g_signal_connect(button_, "enter-notify-event",
+  signals_.Connect(button_, "enter-notify-event",
                    G_CALLBACK(OnEnterThunk), this);
-  g_signal_connect(button_, "leave-notify-event",
+  signals_.Connect(button_, "leave-notify-event",
                    G_CALLBACK(OnLeaveThunk), this);
-  g_signal_connect(button_, "destroy",
-                   G_CALLBACK(OnButtonDestroyThunk), this);
+  signals_.Connect(button_, "destroy",
+                   G_CALLBACK(OnDestroyThunk), this);
 
 #ifndef NDEBUG
   if (g_object_get_data(G_OBJECT(button_), kHoverControllerGtkKey))
     NOTREACHED();
 #endif  // !NDEBUG
 
   g_object_set_data(G_OBJECT(button), kHoverControllerGtkKey, this);
 }
 
 HoverControllerGtk::~HoverControllerGtk() {
@@ skipping 12 matching lines @@
 
 // static
 HoverControllerGtk* HoverControllerGtk::GetHoverControllerGtk(
     GtkWidget* button) {
   return reinterpret_cast<HoverControllerGtk*>(
       g_object_get_data(G_OBJECT(button), kHoverControllerGtkKey));
 }
 
 void HoverControllerGtk::Destroy() {
   gtk_chrome_button_set_hover_state(GTK_CHROME_BUTTON(button_), -1.0);
-  g_signal_handlers_disconnect_by_func(
-      button_,
-      reinterpret_cast<gpointer>(OnButtonDestroyThunk),
-      this);

[Elliot Glaysher, 2010/04/28 16:39:13]

I'm not so sure that these are equivalent. Previously, you were disconnecting
from button_'s OnButtonDestroyThunk before you called g_object_unref(button_).
Now that will happen afterwards. And why disconnect here in the destroy thunk at
all?

[Evan Stade, 2010/04/28 19:00:51]

it's not equivalent, but I believe the new code to be correct. Also note that
the other two signal handlers were not being disconnected when
HoverControllerGtk was destructed, which is a bug, and is exactly what the
signal registrar is designed to prevent.
yea, not much point since the signal handler will disconnect itself on destroy.

+
   g_object_set_data(G_OBJECT(button_), kHoverControllerGtkKey, NULL);
   g_object_unref(button_);
   button_ = NULL;
 
   delete this;
 }
 
 void HoverControllerGtk::AnimationProgressed(const Animation* animation) {
   if (!button_)
     return;
@@ skipping 33 matching lines @@
   if (event->state & (GDK_BUTTON1_MASK | GDK_BUTTON2_MASK | GDK_BUTTON3_MASK)) {
     hover_animation_.Reset();
     gtk_chrome_button_set_hover_state(GTK_CHROME_BUTTON(button_), 0);
   } else {
     hover_animation_.Hide();
   }
 
   return FALSE;
 }
 
-void HoverControllerGtk::OnButtonDestroy(GtkWidget* widget) {
+void HoverControllerGtk::OnDestroy(GtkWidget* widget) {
   Destroy();
 }