blob: 28e567bbafce2348d0f754e16d6b607f49d36019 [file] [log] [blame]
// Copyright (c) 2012 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 "ui/gfx/win/singleton_hwnd.h"
#include "base/memory/singleton.h"
#include "base/message_loop/message_loop.h"
#include "ui/gfx/win/singleton_hwnd_observer.h"
namespace gfx {
// static
SingletonHwnd* SingletonHwnd::GetInstance() {
return base::Singleton<SingletonHwnd>::get();
BOOL SingletonHwnd::ProcessWindowMessage(HWND window,
UINT message,
WPARAM wparam,
LPARAM lparam,
LRESULT& result,
DWORD msg_map_id) {
if (!base::MessageLoopCurrentForUI::IsSet()) {
// If there is no MessageLoop and SingletonHwnd is receiving messages, this
// means it is receiving messages via an external message pump such as COM
// uninitialization.
// It is unsafe to forward these messages as observers may depend on the
// existence of a MessageLoop to proceed.
return false;
for (SingletonHwndObserver& observer : observer_list_)
observer.OnWndProc(window, message, wparam, lparam);
return false;
SingletonHwnd::SingletonHwnd() {
if (!base::MessageLoopCurrentForUI::IsSet()) {
// Creating this window in (e.g.) a renderer inhibits shutdown on
// Windows. See and
WindowImpl::Init(NULL, Rect());
SingletonHwnd::~SingletonHwnd() {
// WindowImpl will clean up the hwnd value on WM_NCDESTROY.
if (hwnd())
// Tell all of our current observers to clean themselves up.
for (SingletonHwndObserver& observer : observer_list_)
void SingletonHwnd::AddObserver(SingletonHwndObserver* observer) {
void SingletonHwnd::RemoveObserver(SingletonHwndObserver* observer) {
} // namespace gfx