Destroy the TaskManagerGtk singleton instance when its window is destroyed, o...

chrome/browser/gtk/task_manager_gtk.cc

 // Copyright (c) 2009 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/task_manager_gtk.h"
 
 #include <gdk/gdkkeysyms.h>
 
 #include <algorithm>
 #include <vector>
 
 #include "app/gfx/gtk_util.h"
 #include "app/l10n_util.h"
 #include "app/resource_bundle.h"
 #include "base/logging.h"
-#include "chrome/browser/browser_list.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/browser_window.h"
 #include "chrome/browser/gtk/gtk_chrome_link_button.h"
 #include "chrome/browser/gtk/gtk_theme_provider.h"
 #include "chrome/browser/gtk/menu_gtk.h"
 #include "chrome/common/gtk_tree.h"
 #include "chrome/common/gtk_util.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/pref_service.h"
 #include "grit/app_resources.h"
 #include "grit/chromium_strings.h"
 
@@ skipping 231 matching lines @@
 
 TaskManagerGtk::~TaskManagerGtk() {
   task_manager_->OnWindowClosed();
   model_->RemoveObserver(this);
 
   gtk_accel_group_disconnect_key(accel_group_, GDK_w, GDK_CONTROL_MASK);
   gtk_window_remove_accel_group(GTK_WINDOW(dialog_), accel_group_);
   g_object_unref(accel_group_);
   accel_group_ = NULL;
 
+  // Disconnect the destroy signal so it doesn't delete |this|.
+  g_signal_handler_disconnect(G_OBJECT(dialog_), destroy_handler_id_);
   gtk_widget_destroy(dialog_);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // TaskManagerGtk, TaskManagerModelObserver implementation:
 
 void TaskManagerGtk::OnModelChanged() {
   // Nothing to do.
 }
 
@@ skipping 88 matching lines @@
   // Setting the link widget to secondary positions the button on the left side
   // of the action area (vice versa for RTL layout).
   gtk_button_box_set_child_secondary(
       GTK_BUTTON_BOX(GTK_DIALOG(dialog_)->action_area), link, TRUE);
 
   ConnectAccelerators();
 
   gtk_box_set_spacing(GTK_BOX(GTK_DIALOG(dialog_)->vbox),
                       gtk_util::kContentAreaSpacing);
 
+  destroy_handler_id_ = g_signal_connect(G_OBJECT(dialog_), "destroy",
+                                         G_CALLBACK(OnDestroy), this);
   g_signal_connect(G_OBJECT(dialog_), "response", G_CALLBACK(OnResponse), this);
   g_signal_connect(G_OBJECT(dialog_), "button-release-event",
                    G_CALLBACK(OnButtonReleaseEvent), this);
   gtk_widget_add_events(dialog_,
                         GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK);
 
   // Wrap the treeview widget in a scrolled window in order to have a frame.
   GtkWidget* scrolled = gtk_scrolled_window_new(NULL, NULL);
   gtk_scrolled_window_set_shadow_type(GTK_SCROLLED_WINDOW(scrolled),
                                       GTK_SHADOW_ETCHED_IN);
@@ skipping 277 matching lines @@
 }
 
 gint TaskManagerGtk::CompareImpl(GtkTreeModel* model, GtkTreeIter* a,
                                  GtkTreeIter* b, int id) {
   int row1 = gtk_tree::GetRowNumForIter(model, a);
   int row2 = gtk_tree::GetRowNumForIter(model, b);
   return model_->CompareValues(row1, row2, id);
 }
 
 // static
+void TaskManagerGtk::OnDestroy(GtkDialog* dialog,
+                               TaskManagerGtk* task_manager) {
+  instance_ = NULL;
+  delete task_manager;
+}
+
+// static
 void TaskManagerGtk::OnResponse(GtkDialog* dialog, gint response_id,
                                 TaskManagerGtk* task_manager) {
   if (response_id == GTK_RESPONSE_DELETE_EVENT) {
     // Store the dialog's size so we can restore it the next time it's opened.
     if (g_browser_process->local_state()) {
       gint x = 0, y = 0, width = 1, height = 1;
       gtk_window_get_position(GTK_WINDOW(dialog), &x, &y);
       gtk_window_get_size(GTK_WINDOW(dialog), &width, &height);
 
       DictionaryValue* placement_pref =
@@ skipping 98 matching lines @@
                                           TaskManagerGtk* task_manager) {
   if (keyval == GDK_w && modifier == GDK_CONTROL_MASK) {
     // The GTK_RESPONSE_DELETE_EVENT response must be sent before the widget
     // is destroyed.  The deleted object will receive gtk signals otherwise.
     gtk_dialog_response(GTK_DIALOG(task_manager->dialog_),
                         GTK_RESPONSE_DELETE_EVENT);
   }
 
   return TRUE;
 }