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 void Env::DeleteInstance() {
  47   delete lazy_tls_ptr.Pointer()->Get();
  48 }
  49
  50 void Env::AddObserver(EnvObserver* observer) {
  51   observers_.AddObserver(observer);
  52 }
  53
  54 void Env::RemoveObserver(EnvObserver* observer) {
  55   observers_.RemoveObserver(observer);
  56 }
  57
  58 bool Env::IsMouseButtonDown() const {
  59   return input_state_lookup_.get() ? input_state_lookup_->IsMouseButtonDown() :
  60       mouse_button_flags_ != 0;
  61 }
  62
  63 ////////////////////////////////////////////////////////////////////////////////
  64 // Env, private:
  65
  66 Env::Env()
  67     : mouse_button_flags_(0),
  68       is_touch_down_(false),
  69       input_state_lookup_(InputStateLookup::Create().Pass()),
  70       context_factory_(NULL) {
  71   DCHECK(lazy_tls_ptr.Pointer()->Get() == NULL);
  72   lazy_tls_ptr.Pointer()->Set(this);
  73 }
  74
  75 Env::~Env() {
  76   FOR_EACH_OBSERVER(EnvObserver, observers_, OnWillDestroyEnv());
  77   DCHECK_EQ(this, lazy_tls_ptr.Pointer()->Get());
  78   lazy_tls_ptr.Pointer()->Set(NULL);
  79 }
  80
  81 void Env::Init(bool create_event_source) {
  82 #if defined(USE_OZONE)
  83   // The ozone platform can provide its own event source. So initialize the
  84   // platform before creating the default event source.
  85   ui::OzonePlatform::InitializeForUI();
  86 #endif
  87   if (create_event_source && !ui::PlatformEventSource::GetInstance())
  88     event_source_ = ui::PlatformEventSource::CreateDefault();
  89 }
  90
  91 void Env::NotifyWindowInitialized(Window* window) {
  92   FOR_EACH_OBSERVER(EnvObserver, observers_, OnWindowInitialized(window));
  93 }
  94
  95 void Env::NotifyHostInitialized(WindowTreeHost* host) {
  96   FOR_EACH_OBSERVER(EnvObserver, observers_, OnHostInitialized(host));
  97 }
  98
  99 void Env::NotifyHostActivated(WindowTreeHost* host) {
 100   FOR_EACH_OBSERVER(EnvObserver, observers_, OnHostActivated(host));
 101 }
 102
 103 ////////////////////////////////////////////////////////////////////////////////
 104 // Env, ui::EventTarget implementation:
 105
 106 bool Env::CanAcceptEvent(const ui::Event& event) {
 107   return true;
 108 }
 109
 110 ui::EventTarget* Env::GetParentTarget() {
 111   return NULL;
 112 }
 113
 114 scoped_ptr<ui::EventTargetIterator> Env::GetChildIterator() const {
 115   return scoped_ptr<ui::EventTargetIterator>();
 116 }
 117
 118 ui::EventTargeter* Env::GetEventTargeter() {
 119   NOTREACHED();
 120   return NULL;
 121 }
 122
 123 }  // namespace aura