// 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/display/display_observer.h" #include "ui/display/screen.h" #include "ui/display/tablet_state.h" namespace display { DisplayObserver::~DisplayObserver() {} void DisplayObserver::OnWillProcessDisplayChanges() {} void DisplayObserver::OnDidProcessDisplayChanges() {} void DisplayObserver::OnDisplayAdded(const Display& new_display) {} void DisplayObserver::OnDisplayRemoved(const Display& old_display) {} void DisplayObserver::OnDidRemoveDisplays() {} void DisplayObserver::OnDisplayMetricsChanged(const Display& display, uint32_t changed_metrics) {} void DisplayObserver::OnCurrentWorkspaceChanged( const std::string& new_workspace) {} void DisplayObserver::OnDisplayTabletStateChanged(TabletState state) {} ScopedOptionalDisplayObserver::ScopedOptionalDisplayObserver( DisplayObserver* observer) { if (auto* screen = display::Screen::GetScreen()) { observer_ = observer; screen->AddObserver(observer_); } } ScopedOptionalDisplayObserver::~ScopedOptionalDisplayObserver() { if (!observer_) return; if (auto* screen = display::Screen::GetScreen()) screen->RemoveObserver(observer_); } ScopedDisplayObserver::ScopedDisplayObserver(DisplayObserver* observer) : ScopedOptionalDisplayObserver(observer) { CHECK(Screen::GetScreen()); } } // namespace display