src/xwalk/sysapps/device_capabilities/display_info_provider.cc

   1 // Copyright (c) 2013 Intel Corporation. All rights reserved.
   2 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   3 // Use of this source code is governed by a BSD-style license that can be
   4 // found in the LICENSE file.
   5
   6 #include "xwalk/sysapps/device_capabilities/display_info_provider.h"
   7
   8 #include <vector>
   9 #include "base/strings/string_number_conversions.h"
  10 #include "base/sys_info.h"
  11 #include "ui/gfx/display.h"
  12 #include "ui/gfx/screen.h"
  13
  14 using xwalk::jsapi::device_capabilities::DisplayUnit;
  15
  16 namespace {
  17
  18 // We are calculating the DPI the same way Chromium for
  19 // ChromiumOS. See display_info_provider_chromeos.cc.
  20 const float kDpi96 = 96;
  21
  22 linked_ptr<DisplayUnit> makeDisplayUnit(const gfx::Display& display) {
  23   gfx::Screen* screen = gfx::Screen::GetNativeScreen();
  24   const int64 primary_display_id = screen->GetPrimaryDisplay().id();
  25
  26   linked_ptr<DisplayUnit> display_unit(new DisplayUnit);
  27
  28   display_unit->id = base::Int64ToString(display.id());
  29   // FIXME(YuZhiqiangX): find which field reflects 'name'.
  30   display_unit->name = "unknown";
  31
  32   display_unit->is_primary = (display.id() == primary_display_id);
  33   display_unit->is_internal = display.IsInternal();
  34
  35   const float dpi = display.device_scale_factor() * kDpi96;
  36   display_unit->dpi_x = static_cast<unsigned int>(dpi);
  37   display_unit->dpi_y = static_cast<unsigned int>(dpi);
  38
  39   display_unit->width = display.bounds().width();
  40   display_unit->height = display.bounds().height();
  41   display_unit->avail_width = display.work_area_size().width();
  42   display_unit->avail_height = display.work_area_size().height();
  43
  44   return display_unit;
  45 }
  46
  47 }  // namespace
  48
  49 namespace xwalk {
  50 namespace sysapps {
  51
  52 DisplayInfoProvider::DisplayInfoProvider() {}
  53
  54 DisplayInfoProvider::~DisplayInfoProvider() {}
  55
  56 // static
  57 scoped_ptr<SystemDisplay> DisplayInfoProvider::display_info() {
  58   scoped_ptr<SystemDisplay> info(new SystemDisplay);
  59
  60   gfx::Screen* screen = gfx::Screen::GetNativeScreen();
  61   std::vector<gfx::Display> displays = screen->GetAllDisplays();
  62
  63   for (std::vector<gfx::Display>::const_iterator it = displays.begin();
  64       it != displays.end(); ++it) {
  65     info->displays.push_back(makeDisplayUnit(*it));
  66   }
  67
  68   return info.Pass();
  69 }
  70
  71 void DisplayInfoProvider::AddObserver(Observer* observer) {
  72   bool should_start_monitoring = false;
  73   if (!observer_list_.might_have_observers())
  74     should_start_monitoring = true;
  75
  76   observer_list_.AddObserver(observer);
  77
  78   if (should_start_monitoring)
  79     StartDisplayMonitoring();
  80 }
  81
  82 void DisplayInfoProvider::RemoveObserver(Observer* observer) {
  83   observer_list_.RemoveObserver(observer);
  84
  85   if (!observer_list_.might_have_observers())
  86     StopDisplayMonitoring();
  87 }
  88
  89 bool DisplayInfoProvider::HasObserver(Observer* observer) const {
  90   return observer_list_.HasObserver(observer);
  91 }
  92
  93 void DisplayInfoProvider::StartDisplayMonitoring() {
  94   gfx::Screen* screen = gfx::Screen::GetNativeScreen();
  95   screen->AddObserver(this);
  96 }
  97
  98 void DisplayInfoProvider::StopDisplayMonitoring() {
  99   gfx::Screen* screen = gfx::Screen::GetNativeScreen();
 100   screen->RemoveObserver(this);
 101 }
 102
 103 void DisplayInfoProvider::OnDisplayAdded(const gfx::Display& display) {
 104   FOR_EACH_OBSERVER(Observer,
 105                     observer_list_,
 106                     OnDisplayConnected(*makeDisplayUnit(display)));
 107 }
 108
 109 void DisplayInfoProvider::OnDisplayRemoved(const gfx::Display& display) {
 110   FOR_EACH_OBSERVER(Observer,
 111                     observer_list_,
 112                     OnDisplayDisconnected(*makeDisplayUnit(display)));
 113 }
 114
 115 }  // namespace sysapps
 116 }  // namespace xwalk