Implement DeviceMotionEvent API

chromeos/accelerometer/accelerometer_reader.cc

 // Copyright 2014 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 "chromeos/accelerometer/accelerometer_reader.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/files/file_util.h"
@@ skipping 184 matching lines @@
   // Asynchronously detect and initialize the accelerometer to avoid delaying
   // startup.
   base::PostTaskAndReplyWithResult(
       task_runner_.get(), FROM_HERE,
       base::Bind(&DetectAndReadAccelerometerConfiguration, configuration_),
       base::Bind(&AccelerometerReader::OnInitialized,
                  weak_factory_.GetWeakPtr(), configuration_));
 }
 
 void AccelerometerReader::AddObserver(Observer* observer) {
-  observers_.AddObserver(observer);
-  if (has_update_)
-    observer->OnAccelerometerUpdated(update_);
+  observers_->AddObserver(observer);
+  if (update_.get())

[flackr, 2015/03/02 15:46:39]

I believe scoped_refptr is testable (i.e. can just say if (update) ).

[jonross, 2015/03/04 21:54:50]

Done.

+    observer->OnAccelerometerUpdated(update_.get());
 }
 
 void AccelerometerReader::RemoveObserver(Observer* observer) {
-  observers_.RemoveObserver(observer);
+  observers_->RemoveObserver(observer);
+}
+
+bool AccelerometerReader::HasObserver(Observer* observer) {
+  return observers_->HasObserver(observer);
 }
 
 AccelerometerReader::AccelerometerReader()
-    : has_update_(false),
-      configuration_(new AccelerometerReader::Configuration()),
+    : configuration_(new AccelerometerReader::Configuration()),
+      observers_(new ObserverListThreadSafe<Observer>()),
       weak_factory_(this) {
 }
 
 AccelerometerReader::~AccelerometerReader() {
 }
 
 void AccelerometerReader::OnInitialized(
     scoped_refptr<AccelerometerReader::Configuration> configuration,
     bool success) {
   if (success)
@@ skipping 13 matching lines @@
                                               weak_factory_.GetWeakPtr(),
                                               reading));
 }
 
 void AccelerometerReader::OnDataRead(
     scoped_refptr<AccelerometerReader::Reading> reading,
     bool success) {
   DCHECK(!task_runner_->RunsTasksOnCurrentThread());
 
   if (success) {
-    has_update_ = true;
+    update_ = new AccelerometerUpdate();
     for (int i = 0; i < ACCELEROMETER_SOURCE_COUNT; ++i) {
       if (!configuration_->data.has[i])
         continue;
 
       int16* values = reinterpret_cast<int16*>(reading->data);
-      update_.Set(static_cast<AccelerometerSource>(i),
-                  values[configuration_->data.index[i][0]] *
-                      configuration_->data.scale[i][0],
-                  values[configuration_->data.index[i][1]] *
-                      configuration_->data.scale[i][1],
-                  values[configuration_->data.index[i][2]] *
-                      configuration_->data.scale[i][2]);
+      update_->Set(static_cast<AccelerometerSource>(i),
+                   values[configuration_->data.index[i][0]] *
+                       configuration_->data.scale[i][0],
+                   values[configuration_->data.index[i][1]] *
+                       configuration_->data.scale[i][1],
+                   values[configuration_->data.index[i][2]] *
+                       configuration_->data.scale[i][2]);
     }
-    FOR_EACH_OBSERVER(Observer, observers_, OnAccelerometerUpdated(update_));
+    // TODO(jonross): move this to the blocking thread (crbug.com/461433)
+    observers_->Notify(FROM_HERE, &Observer::OnAccelerometerUpdated, update_);
   }
 
   // Trigger another read after the current sampling delay.
   base::MessageLoop::current()->PostDelayedTask(
       FROM_HERE,
       base::Bind(&AccelerometerReader::TriggerRead,
                  weak_factory_.GetWeakPtr()),
       base::TimeDelta::FromMilliseconds(kDelayBetweenReadsMs));
 }
 
 }  // namespace chromeos