blob: 36daf552c9e7016f99f0da1e6880a500b463478d [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.
#ifndef UI_GFX_WIN_SINGLETON_HWND_H_
#define UI_GFX_WIN_SINGLETON_HWND_H_
#include <windows.h>
#include "base/macros.h"
#include "base/observer_list.h"
#include "ui/gfx/gfx_export.h"
#include "ui/gfx/win/window_impl.h"
namespace base {
template<typename T> struct DefaultSingletonTraits;
}
namespace gfx {
class SingletonHwndObserver;
// Singleton message-only HWND that allows interested clients to receive WM_*
// notifications.
class GFX_EXPORT SingletonHwnd : public WindowImpl {
public:
static SingletonHwnd* GetInstance();
SingletonHwnd(const SingletonHwnd&) = delete;
SingletonHwnd& operator=(const SingletonHwnd&) = delete;
// Windows callback for WM_* notifications.
BOOL ProcessWindowMessage(HWND window,
UINT message,
WPARAM wparam,
LPARAM lparam,
LRESULT& result,
DWORD msg_map_id) override;
private:
friend class SingletonHwndObserver;
friend struct base::DefaultSingletonTraits<SingletonHwnd>;
SingletonHwnd();
~SingletonHwnd() override;
// Add/remove SingletonHwndObserver to forward WM_* notifications.
void AddObserver(SingletonHwndObserver* observer);
void RemoveObserver(SingletonHwndObserver* observer);
// List of registered observers.
base::ObserverList<SingletonHwndObserver, true>::Unchecked observer_list_;
};
} // namespace gfx
#endif // UI_GFX_WIN_SINGLETON_HWND_H_