Android 8. +上不会显示前台服务的通知

Question

我的前台服务在Android Oreo上运行时未显示通知。

它在15到25的Android版本上完美运行。当我从26到25执行targetSdkVersion ，此问题消失了。 但是这种解决方案似乎不好。

我准备了与此问题有关的测试项目 。

我如何使用targetSdkVersion 26在Android Oreo上修复它？

我的前台服务SoundService.java（ 完整源代码 ）：

        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 
    ...
            }
        }

我的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'
}

其中project.ext.supportLibVersion = '26.1.0'

看看它如何在Android API <26上工作

Answer 1

步骤＃1：将project.ext.supportLibVersion设置为26.1.0或更高版本

步骤2：请注意，您现在在所有new NotificationCompat.Builder()调用中都收到过时警告

步骤＃3： 定义一个NotificationChannel （如果您在应用程序的某些先前运行中尚未定义它）

步骤＃4：将频道ID传递给NotificationCompat.Builder构造函数

Answer 2

我只是改变了我的方法prepareNotification()在SoundService.java来自：

    private Notification prepareNotification() {
            Intent notificationIntent = new Intent(this, MainActivity.class);
            notificationIntent.setAction(MusicConstants.ACTION.MAIN_ACTION);
            //...
            NotificationCompat.Builder lNotificationBuilder = new NotificationCompat.Builder(this);
           //...

至：

    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);
           }
           //...

您可以在这里看到完整的差异。