1 /* 2 * Copyright (C) 2020 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.car.experimental; 18 19 import android.annotation.NonNull; 20 import android.annotation.Nullable; 21 import android.annotation.RequiresPermission; 22 import android.car.Car; 23 import android.car.CarManagerBase; 24 import android.car.annotation.RequiredFeature; 25 import android.os.Handler; 26 import android.os.IBinder; 27 import android.os.Looper; 28 import android.os.Message; 29 import android.os.RemoteException; 30 import android.util.Log; 31 32 import java.lang.ref.WeakReference; 33 import java.util.concurrent.CopyOnWriteArrayList; 34 35 /** 36 * Experimental APIs that allow clients to consume information about a driver's current distraction 37 * level. 38 * 39 * @hide 40 */ 41 @RequiredFeature(ExperimentalCar.TEST_EXPERIMENTAL_FEATURE_SERVICE) 42 public final class CarDriverDistractionManager extends CarManagerBase { 43 44 private static final String TAG = "CarDriverDistractionManager"; 45 private static final int MSG_HANDLE_DISTRACTION_CHANGE = 0; 46 47 private final IDriverDistractionManager mService; 48 private final EventHandler mEventHandler; 49 50 private final IDriverDistractionChangeListenerImpl mBinderCallback; 51 52 /** 53 * Listener to monitor any changes to the driver's distraction level. 54 */ 55 public interface OnDriverDistractionChangeListener { 56 /** 57 * Called when the driver's distraction level has changed. 58 * 59 * @param event the new driver distraction information. 60 */ onDriverDistractionChange(DriverDistractionChangeEvent event)61 void onDriverDistractionChange(DriverDistractionChangeEvent event); 62 } 63 64 private final CopyOnWriteArrayList<OnDriverDistractionChangeListener> mListeners = 65 new CopyOnWriteArrayList<>(); 66 67 /** 68 * Constructor parameters should remain this way for Car library to construct this. 69 */ CarDriverDistractionManager(Car car, IBinder service)70 public CarDriverDistractionManager(Car car, IBinder service) { 71 super(car); 72 mService = IDriverDistractionManager.Stub.asInterface(service); 73 mEventHandler = new EventHandler(this, getEventHandler().getLooper()); 74 mBinderCallback = new IDriverDistractionChangeListenerImpl(this); 75 } 76 77 /** 78 * Gets the current driver distraction level based on the last change event that is not stale. 79 * 80 * Return {@code null} if there is an internal error. 81 */ 82 @RequiresPermission(value = ExperimentalCar.PERMISSION_READ_CAR_DRIVER_DISTRACTION) 83 @Nullable getLastDistractionEvent()84 public DriverDistractionChangeEvent getLastDistractionEvent() { 85 try { 86 return mService.getLastDistractionEvent(); 87 } catch (RemoteException e) { 88 return handleRemoteExceptionFromCarService(e, null); 89 } 90 } 91 92 /** 93 * Adds a {@link OnDriverDistractionChangeListener} to be notified for changes to the driver's 94 * distraction level. 95 * 96 * <p>The provided listener will immediately receive a callback for the most recent distraction 97 * event. 98 * 99 * @param listener to be added 100 */ 101 @RequiresPermission(value = ExperimentalCar.PERMISSION_READ_CAR_DRIVER_DISTRACTION) addDriverDistractionChangeListener( @onNull OnDriverDistractionChangeListener listener)102 public void addDriverDistractionChangeListener( 103 @NonNull OnDriverDistractionChangeListener listener) { 104 if (mListeners.addIfAbsent(listener)) { 105 if (mListeners.size() == 1) { 106 try { 107 mService.addDriverDistractionChangeListener(mBinderCallback); 108 } catch (RemoteException e) { 109 handleRemoteExceptionFromCarService(e); 110 } 111 } 112 } 113 } 114 115 /** 116 * Removes the listener. Listeners not added before will be ignored. 117 */ 118 @RequiresPermission(value = ExperimentalCar.PERMISSION_READ_CAR_DRIVER_DISTRACTION) removeDriverDistractionChangeListener( @onNull OnDriverDistractionChangeListener listener)119 public void removeDriverDistractionChangeListener( 120 @NonNull OnDriverDistractionChangeListener listener) { 121 if (mListeners.remove(listener)) { 122 if (mListeners.size() == 0) { 123 try { 124 mService.removeDriverDistractionChangeListener(mBinderCallback); 125 } catch (RemoteException ignored) { 126 // ignore for unregistering 127 } 128 } 129 } 130 } 131 132 @Override onCarDisconnected()133 protected void onCarDisconnected() { 134 // nothing to do 135 } 136 dispatchDistractionChangeToClient( DriverDistractionChangeEvent distractionChangeEvent)137 private void dispatchDistractionChangeToClient( 138 DriverDistractionChangeEvent distractionChangeEvent) { 139 if (distractionChangeEvent == null) { 140 return; 141 } 142 for (OnDriverDistractionChangeListener listener : mListeners) { 143 listener.onDriverDistractionChange(distractionChangeEvent); 144 } 145 } 146 147 private static final class EventHandler extends Handler { 148 private final WeakReference<CarDriverDistractionManager> mDistractionManager; 149 EventHandler(CarDriverDistractionManager manager, Looper looper)150 EventHandler(CarDriverDistractionManager manager, Looper looper) { 151 super(looper); 152 mDistractionManager = new WeakReference<>(manager); 153 } 154 155 @Override handleMessage(Message msg)156 public void handleMessage(Message msg) { 157 CarDriverDistractionManager mgr = mDistractionManager.get(); 158 if (mgr == null) { 159 Log.e(TAG, 160 "handleMessage: null reference to distraction manager when handling " 161 + "message for " + msg.what); 162 return; 163 } 164 switch (msg.what) { 165 case MSG_HANDLE_DISTRACTION_CHANGE: 166 mgr.dispatchDistractionChangeToClient((DriverDistractionChangeEvent) msg.obj); 167 break; 168 default: 169 Log.e(TAG, "Unknown msg not handled:" + msg.what); 170 } 171 } 172 dispatchOnDistractionChangedEvent(DriverDistractionChangeEvent event)173 private void dispatchOnDistractionChangedEvent(DriverDistractionChangeEvent event) { 174 sendMessage(obtainMessage(MSG_HANDLE_DISTRACTION_CHANGE, event)); 175 } 176 } 177 178 private static class IDriverDistractionChangeListenerImpl extends 179 IDriverDistractionChangeListener.Stub { 180 private final WeakReference<CarDriverDistractionManager> mDistractionManager; 181 IDriverDistractionChangeListenerImpl(CarDriverDistractionManager manager)182 IDriverDistractionChangeListenerImpl(CarDriverDistractionManager manager) { 183 mDistractionManager = new WeakReference<>(manager); 184 } 185 186 @Override onDriverDistractionChange(DriverDistractionChangeEvent event)187 public void onDriverDistractionChange(DriverDistractionChangeEvent event) { 188 CarDriverDistractionManager manager = mDistractionManager.get(); 189 if (manager != null) { 190 manager.mEventHandler.dispatchOnDistractionChangedEvent(event); 191 } 192 } 193 } 194 } 195