ui/aura/env.cc

   1 // Copyright (c) 2012 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/aura/env.h"
   6
   7 #include "base/lazy_instance.h"
   8 #include "base/threading/thread_local.h"
   9 #include "ui/aura/env_observer.h"
  10 #include "ui/aura/input_state_lookup.h"
  11 #include "ui/events/event_target_iterator.h"
  12 #include "ui/events/platform/platform_event_source.h"
  13
  14 #if defined(USE_OZONE)
  15 #include "ui/ozone/public/ozone_platform.h"
  16 #endif
  17
  18 namespace aura {
  19
  20 namespace {
  21
  22 // Env is thread local so that aura may be used on multiple threads.
  23 base::LazyInstance<base::ThreadLocalPointer<Env> >::Leaky lazy_tls_ptr =
  24     LAZY_INSTANCE_INITIALIZER;
  25
  26 }  // namespace
  27
  28 ////////////////////////////////////////////////////////////////////////////////
  29 // Env, public:
  30
  31 // static
  32 void Env::CreateInstance(bool create_event_source) {
  33   if (!lazy_tls_ptr.Pointer()->Get())
  34     (new Env())->Init(create_event_source);
  35 }
  36
  37 // static
  38 Env* Env::GetInstance() {
  39   Env* env = lazy_tls_ptr.Pointer()->Get();
  40   DCHECK(env) << "Env::CreateInstance must be called before getting the "
  41                  "instance of Env.";
  42   return env;
  43 }
  44
  45 // static
  46 Env* Env::GetInstanceDontCreate() {
  47   return lazy_tls_ptr.Pointer()->Get();
  48 }
  49
  50 // static
  51 void Env::DeleteInstance() {
  52   delete lazy_tls_ptr.Pointer()->Get();
  53 }
  54
  55 void Env::AddObserver(EnvObserver* observer) {
  56   observers_.AddObserver(observer);
  57 }
  58
  59 void Env::RemoveObserver(EnvObserver* observer) {
  60   observers_.RemoveObserver(observer);
  61 }
  62
  63 bool Env::IsMouseButtonDown() const {
  64   return input_state_lookup_.get() ? input_state_lookup_->IsMouseButtonDown() :
  65       mouse_button_flags_ != 0;
  66 }
  67
  68 ////////////////////////////////////////////////////////////////////////////////
  69 // Env, private:
  70
  71 Env::Env()
  72     : mouse_button_flags_(0),
  73       is_touch_down_(false),
  74       input_state_lookup_(InputStateLookup::Create().Pass()),
  75       context_factory_(NULL) {
  76   DCHECK(lazy_tls_ptr.Pointer()->Get() == NULL);
  77   lazy_tls_ptr.Pointer()->Set(this);
  78 }
  79
  80 Env::~Env() {
  81   FOR_EACH_OBSERVER(EnvObserver, observers_, OnWillDestroyEnv());
  82   DCHECK_EQ(this, lazy_tls_ptr.Pointer()->Get());
  83   lazy_tls_ptr.Pointer()->Set(NULL);
  84 }
  85
  86 void Env::Init(bool create_event_source) {
  87 #if defined(USE_OZONE)
  88   // The ozone platform can provide its own event source. So initialize the
  89   // platform before creating the default event source.
  90   ui::OzonePlatform::InitializeForUI();
  91 #endif
  92   if (create_event_source && !ui::PlatformEventSource::GetInstance())
  93     event_source_ = ui::PlatformEventSource::CreateDefault();
  94 }
  95
  96 void Env::NotifyWindowInitialized(Window* window) {
  97   FOR_EACH_OBSERVER(EnvObserver, observers_, OnWindowInitialized(window));
  98 }
  99
 100 void Env::NotifyHostInitialized(WindowTreeHost* host) {
 101   FOR_EACH_OBSERVER(EnvObserver, observers_, OnHostInitialized(host));
 102 }
 103
 104 void Env::NotifyHostActivated(WindowTreeHost* host) {
 105   FOR_EACH_OBSERVER(EnvObserver, observers_, OnHostActivated(host));
 106 }
 107
 108 ////////////////////////////////////////////////////////////////////////////////
 109 // Env, ui::EventTarget implementation:
 110
 111 bool Env::CanAcceptEvent(const ui::Event& event) {
 112   return true;
 113 }
 114
 115 ui::EventTarget* Env::GetParentTarget() {
 116   return NULL;
 117 }
 118
 119 scoped_ptr<ui::EventTargetIterator> Env::GetChildIterator() const {
 120   return nullptr;
 121 }
 122
 123 ui::EventTargeter* Env::GetEventTargeter() {
 124   NOTREACHED();
 125   return NULL;
 126 }
 127
 128 }  // namespace aura