1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "ui/gfx/display_change_notifier.h" 6 7 #include "ui/gfx/display.h" 8 #include "ui/gfx/display_observer.h" 9 10 namespace gfx { 11 12 namespace { 13 14 class DisplayComparator { 15 public: 16 explicit DisplayComparator(const Display& display) 17 : display_id_(display.id()) 18 {} 19 20 bool operator()(const Display& display) const { 21 return display.id() == display_id_; 22 } 23 24 private: 25 int64 display_id_; 26 }; 27 28 } // anonymous namespace 29 30 DisplayChangeNotifier::DisplayChangeNotifier() { 31 } 32 33 DisplayChangeNotifier::~DisplayChangeNotifier() { 34 } 35 36 void DisplayChangeNotifier::AddObserver(DisplayObserver* obs) { 37 observer_list_.AddObserver(obs); 38 } 39 40 void DisplayChangeNotifier::RemoveObserver(DisplayObserver* obs) { 41 observer_list_.RemoveObserver(obs); 42 } 43 44 void DisplayChangeNotifier::NotifyDisplaysChanged( 45 const std::vector<Display>& old_displays, 46 const std::vector<Display>& new_displays) { 47 // Display present in old_displays but not in new_displays has been removed. 48 std::vector<Display>::const_iterator old_it = old_displays.begin(); 49 for (; old_it != old_displays.end(); ++old_it) { 50 if (std::find_if(new_displays.begin(), new_displays.end(), 51 DisplayComparator(*old_it)) == new_displays.end()) { 52 FOR_EACH_OBSERVER(DisplayObserver, observer_list_, 53 OnDisplayRemoved(*old_it)); 54 } 55 } 56 57 // Display present in new_displays but not in old_displays has been added. 58 // Display present in both might have been modified. 59 for (std::vector<Display>::const_iterator new_it = 60 new_displays.begin(); new_it != new_displays.end(); ++new_it) { 61 std::vector<Display>::const_iterator old_it = std::find_if( 62 old_displays.begin(), old_displays.end(), DisplayComparator(*new_it)); 63 64 if (old_it == old_displays.end()) { 65 FOR_EACH_OBSERVER(DisplayObserver, observer_list_, 66 OnDisplayAdded(*new_it)); 67 continue; 68 } 69 70 uint32_t metrics = DisplayObserver::DISPLAY_METRIC_NONE; 71 72 if (new_it->bounds() != old_it->bounds()) 73 metrics |= DisplayObserver::DISPLAY_METRIC_BOUNDS; 74 75 if (new_it->rotation() != old_it->rotation()) 76 metrics |= DisplayObserver::DISPLAY_METRIC_ROTATION; 77 78 if (new_it->work_area() != old_it->work_area()) 79 metrics |= DisplayObserver::DISPLAY_METRIC_WORK_AREA; 80 81 if (new_it->device_scale_factor() != old_it->device_scale_factor()) 82 metrics |= DisplayObserver::DISPLAY_METRIC_DEVICE_SCALE_FACTOR; 83 84 if (metrics != DisplayObserver::DISPLAY_METRIC_NONE) { 85 FOR_EACH_OBSERVER(DisplayObserver, 86 observer_list_, 87 OnDisplayMetricsChanged(*new_it, metrics)); 88 } 89 } 90 } 91 92 } // namespace gfx 93