My foreground service doesn't show a notification when it works on Android Oreo.
It works perfectly on Android versions from 15 to 25.
When I do targetSdkVersion from 26 to 25 this issue disappears. But this solution seems not good.
I prepared test project with this issue.
What should I do for fixing it on Android Oreo with targetSdkVersion 26?
My foreground service, SoundService.java(full source):
public class SoundService extends Service implements MediaPlayer.OnErrorListener, MediaPlayer.OnPreparedListener, MediaPlayer.OnBufferingUpdateListener {
private final static String TAG = SoundService.class.getSimpleName();
static private int mStateService = MusicConstants.STATE_SERVICE.NOT_INIT;
private final Uri mUriRadioDefault = Uri.parse("https://nfw.ria.ru/flv/audio.aspx?ID=75651129&type=mp3");
private final Object mLock = new Object();
private final Handler mHandler = new Handler();
private MediaPlayer mPlayer;
private Uri mUriRadio;
private NotificationManager mNotificationManager;
private WifiManager.WifiLock mWiFiLock;
private PowerManager.WakeLock mWakeLock;
private Handler mTimerUpdateHandler = new Handler();
private Runnable mTimerUpdateRunnable = new Runnable() {
@Override
public void run() {
mNotificationManager.notify(MusicConstants.NOTIFICATION_ID_FOREGROUND_SERVICE, prepareNotification());
mTimerUpdateHandler.postDelayed(this, MusicConstants.DELAY_UPDATE_NOTIFICATION_FOREGROUND_SERVICE);
}
};
private Runnable mDelayedShutdown = new Runnable() {
public void run() {
unlockWiFi();
unlockCPU();
stopForeground(true);
stopSelf();
}
};
public SoundService() {
}
public static int getState() {
return mStateService;
}
@Override
public IBinder onBind(Intent arg0) {
return null;
}
@Override
public void onCreate() {
super.onCreate();
mStateService = MusicConstants.STATE_SERVICE.NOT_INIT;
mNotificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
mUriRadio = mUriRadioDefault;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
if (intent == null) {
stopForeground(true);
stopSelf();
return START_NOT_STICKY;
}
switch (intent.getAction()) {
case MusicConstants.ACTION.START_ACTION:
mStateService = MusicConstants.STATE_SERVICE.PREPARE;
startForeground(MusicConstants.NOTIFICATION_ID_FOREGROUND_SERVICE, prepareNotification());
destroyPlayer();
initPlayer();
play();
break;
case MusicConstants.ACTION.PAUSE_ACTION:
mStateService = MusicConstants.STATE_SERVICE.PAUSE;
mNotificationManager.notify(MusicConstants.NOTIFICATION_ID_FOREGROUND_SERVICE, prepareNotification());
destroyPlayer();
mHandler.postDelayed(mDelayedShutdown, MusicConstants.DELAY_SHUTDOWN_FOREGROUND_SERVICE);
break;
case MusicConstants.ACTION.PLAY_ACTION:
mStateService = MusicConstants.STATE_SERVICE.PREPARE;
mNotificationManager.notify(MusicConstants.NOTIFICATION_ID_FOREGROUND_SERVICE, prepareNotification());
destroyPlayer();
initPlayer();
play();
break;
case MusicConstants.ACTION.STOP_ACTION:
Log.i(TAG, "Received Stop Intent");
destroyPlayer();
stopForeground(true);
stopSelf();
break;
default:
stopForeground(true);
stopSelf();
}
return START_NOT_STICKY;
}
@Override
public void onDestroy() {
destroyPlayer();
mStateService = MusicConstants.STATE_SERVICE.NOT_INIT;
try {
mTimerUpdateHandler.removeCallbacksAndMessages(null);
} catch (Exception e) {
e.printStackTrace();
}
super.onDestroy();
}
private void destroyPlayer() {
if (mPlayer != null) {
try {
mPlayer.reset();
mPlayer.release();
} catch (Exception e) {
e.printStackTrace();
} finally {
mPlayer = null;
}
}
unlockWiFi();
unlockCPU();
}
public boolean onError(MediaPlayer mp, int what, int extra) {
destroyPlayer();
mHandler.postDelayed(mDelayedShutdown, MusicConstants.DELAY_SHUTDOWN_FOREGROUND_SERVICE);
mNotificationManager.notify(MusicConstants.NOTIFICATION_ID_FOREGROUND_SERVICE, prepareNotification());
mStateService = MusicConstants.STATE_SERVICE.PAUSE;
return false;
}
...
//Part of code was skipped
...
private Notification prepareNotification() {
Intent notificationIntent = new Intent(this, MainActivity.class);
notificationIntent.setAction(MusicConstants.ACTION.MAIN_ACTION);
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.HONEYCOMB) {
notificationIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
} else {
notificationIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
}
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, PendingIntent.FLAG_UPDATE_CURRENT);
Intent lPauseIntent = new Intent(this, SoundService.class);
lPauseIntent.setAction(MusicConstants.ACTION.PAUSE_ACTION);
PendingIntent lPendingPauseIntent = PendingIntent.getService(this, 0, lPauseIntent, PendingIntent.FLAG_UPDATE_CURRENT);
Intent playIntent = new Intent(this, SoundService.class);
playIntent.setAction(MusicConstants.ACTION.PLAY_ACTION);
PendingIntent lPendingPlayIntent = PendingIntent.getService(this, 0, playIntent, PendingIntent.FLAG_UPDATE_CURRENT);
Intent lStopIntent = new Intent(this, SoundService.class);
lStopIntent.setAction(MusicConstants.ACTION.STOP_ACTION);
PendingIntent lPendingStopIntent = PendingIntent.getService(this, 0, lStopIntent, PendingIntent.FLAG_UPDATE_CURRENT);
RemoteViews lRemoteViews = new RemoteViews(getPackageName(), R.layout.radio_notification);
lRemoteViews.setOnClickPendingIntent(R.id.ui_notification_close_button, lPendingStopIntent);
switch (mStateService) {
case MusicConstants.STATE_SERVICE.PAUSE:
lRemoteViews.setViewVisibility(R.id.ui_notification_progress_bar, View.INVISIBLE);
lRemoteViews.setOnClickPendingIntent(R.id.ui_notification_player_button, lPendingPlayIntent);
lRemoteViews.setImageViewResource(R.id.ui_notification_player_button, R.drawable.ic_play_arrow_white);
break;
case MusicConstants.STATE_SERVICE.PLAY:
lRemoteViews.setViewVisibility(R.id.ui_notification_progress_bar, View.INVISIBLE);
lRemoteViews.setOnClickPendingIntent(R.id.ui_notification_player_button, lPendingPauseIntent);
lRemoteViews.setImageViewResource(R.id.ui_notification_player_button, R.drawable.ic_pause_white);
break;
case MusicConstants.STATE_SERVICE.PREPARE:
lRemoteViews.setViewVisibility(R.id.ui_notification_progress_bar, View.VISIBLE);
lRemoteViews.setOnClickPendingIntent(R.id.ui_notification_player_button, lPendingPauseIntent);
lRemoteViews.setImageViewResource(R.id.ui_notification_player_button, R.drawable.ic_pause_white);
break;
}
NotificationCompat.Builder lNotificationBuilder = new NotificationCompat.Builder(this);
lNotificationBuilder
.setContent(lRemoteViews)
.setSmallIcon(R.mipmap.ic_launcher)
.setCategory(NotificationCompat.CATEGORY_TRANSPORT)
.setOngoing(true)
.setAutoCancel(true)
.setContentIntent(pendingIntent);
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP) {
lNotificationBuilder.setVisibility(Notification.VISIBILITY_PUBLIC);
}
return lNotificationBuilder.build();
}
@Override
public void onPrepared(MediaPlayer mp) {
mStateService = MusicConstants.STATE_SERVICE.PLAY;
mNotificationManager.notify(MusicConstants.NOTIFICATION_ID_FOREGROUND_SERVICE, prepareNotification());
try {
mPlayer.setWakeMode(this, PowerManager.PARTIAL_WAKE_LOCK);
} catch (Exception e) {
e.printStackTrace();
}
mPlayer.start();
mTimerUpdateHandler.postDelayed(mTimerUpdateRunnable, 0);
}
private void lockCPU() {
...
//Part of code was skipped
...
}
private void unlockCPU() {
...
//Part of code was skipped
...
}
private void lockWiFi() {
...
//Part of code was skipped
...
}
private void unlockWiFi() {
...
//Part of code was skipped
...
}
}
My build.gradle:
apply plugin: 'com.android.application'
repositories {
maven { url 'https://maven.google.com' }
}
android {
compileSdkVersion 26
buildToolsVersion "26.0.1"
defaultConfig {
applicationId "com.example.foreground"
minSdkVersion 15
targetSdkVersion 26
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
exclude group: 'com.android.support', module: 'support-annotations'
})
compile "com.android.support:support-compat:${project.ext.supportLibVersion}"
compile "com.android.support:support-v4:${project.ext.supportLibVersion}"
compile "com.android.support:design:${project.ext.supportLibVersion}"
compile "com.android.support:appcompat-v7:${project.ext.supportLibVersion}"
compile 'com.android.support.constraint:constraint-layout:1.0.2'
testCompile 'junit:junit:4.12'
}
Where project.ext.supportLibVersion = '26.1.0'
See how it works on Android API < 26 
Step #1: Set project.ext.supportLibVersion to 26.1.0 or higher
Step #2: Note that you are now getting deprecation warnings on all your new NotificationCompat.Builder() calls
Step #3: Define a NotificationChannel (if you have not defined it on some previous run of the app)
Step #4: Pass the channel ID to the NotificationCompat.Builder constructor
I've just changed my method prepareNotification() in SoundService.java from:
private Notification prepareNotification() {
Intent notificationIntent = new Intent(this, MainActivity.class);
notificationIntent.setAction(MusicConstants.ACTION.MAIN_ACTION);
//...
NotificationCompat.Builder lNotificationBuilder = new NotificationCompat.Builder(this);
//...
to:
private Notification prepareNotification() {
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O &&
mNotificationManager.getNotificationChannel(FOREGROUND_CHANNEL_ID) == null) {
// The user-visible name of the channel.
CharSequence name = getString(R.string.text_value_radio_notification);
int importance = NotificationManager.IMPORTANCE_DEFAULT;
NotificationChannel mChannel = new NotificationChannel(FOREGROUND_CHANNEL_ID, name, importance);
mChannel.enableVibration(false);
mNotificationManager.createNotificationChannel(mChannel);
}
Intent notificationIntent = new Intent(this, MainActivity.class);
notificationIntent.setAction(MusicConstants.ACTION.MAIN_ACTION);
//...
NotificationCompat.Builder lNotificationBuilder;
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
lNotificationBuilder = new NotificationCompat.Builder(this, FOREGROUND_CHANNEL_ID);
} else {
lNotificationBuilder = new NotificationCompat.Builder(this);
}
//...
You can see the full difference here.
来源：https://stackoverflow.com/questions/46477571/a-notification-of-the-foreground-service-doesnt-show-on-android-8