如何在Android上正确发送重复通知

我在Android上设置了一个重复通知，但是闹钟没有出现在我的设备上

我已经阅读了Android开发者的文档，根据它，我的代码看起来很好，但仍然不能正常运行。我使用一个类作为BroadcastReceiver，它从MainActivity接收意图，然后将其传递给IntentService

这是在MainActivity上触发报警的方法，它在每次初始化应用程序时运行

 public void setAlarm(){
            alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);

            alarmIntent = new Intent(MainActivity.this, AlarmReceiver.class);
            pendingIntent = PendingIntent.getBroadcast(  MainActivity.this, 0, alarmIntent, 0);

            Calendar alarmStartTime = Calendar.getInstance();
            alarmStartTime.set(Calendar.HOUR_OF_DAY, 16);
            alarmStartTime.set(Calendar.MINUTE, 36);
            alarmStartTime.set(Calendar.SECOND, 0);
            alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, alarmStartTime.getTimeInMillis(), AlarmManager.INTERVAL_DAY, pendingIntent);
            Log.i(TAG,"Alarms set every day.");

        }

这是使用BroadcastReceiver的类

public class AlarmReceiver extends BroadcastReceiver {

    private static final String TAG = "FOCUSALARM";


    @Override
    public void onReceive(Context context, Intent intent) {
        Log.i(TAG, "BroadcastReceiver has received alarm intent.");
        Intent service1 = new Intent(context, AlarmService.class);
        context.startService(service1);

    }

}

这是使用IntentService的类

public class AlarmService extends IntentService
{

    private static final int NOTIFICATION_ID = 101;
    private static final String TAG = "FOCUSALARM";


    public AlarmService() {
        super("AlarmService");
    }


    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        return super.onStartCommand(intent,flags,startId);
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        // don't notify if they've played in last 24 hr
        Log.i(TAG,"Alarm Service has started.");
        Context context = this.getApplicationContext();


        Intent mIntent = new Intent(this, MainActivity.class);
        Bundle bundle = new Bundle();
        bundle.putString("test", "test");
        mIntent.putExtras(bundle);
        PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, mIntent, PendingIntent.FLAG_UPDATE_CURRENT);

        Resources res = this.getResources();
        NotificationCompat.Builder builder = new NotificationCompat.Builder(this, "Focus");

        builder.setContentIntent(pendingIntent)
                .setSmallIcon(R.drawable.ic_launcher)
               // .setLargeIcon(BitmapFactory.decodeResource(res, R.drawable.ic_launcher))
                .setTicker(res.getString(R.string.notification_title))
                .setAutoCancel(true)
                .setContentTitle(res.getString(R.string.notification_title))
                .setContentText(res.getString(R.string.notification_subject));


        NotificationManagerCompat notificationManager =  NotificationManagerCompat.from(this);
        notificationManager.notify(NOTIFICATION_ID, builder.build());
        Log.i(TAG,"Notifications sent.");


    }

当我运行它时，它会显示所有日志，但通知不会出现在设备上

I/FOCUSALARM: Alarms set every day.
I/FOCUSALARM: BroadcastReceiver has received alarm intent.
I/FOCUSALARM: Alarm Service has started.
I/FOCUSALARM: Notifications sent.

---

正如我们感谢的投稿人@RobCo所说：在Oreo+设备中，您必须创建一个通知通道，为此，请使用Android开发者文档中所示的以下方法：

 private void createNotificationChannel() {
        // Create the NotificationChannel, but only on API 26+ because
        // the NotificationChannel class is new and not in the support library
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            CharSequence name = "Hola";
            String description = "Focus bro";
            int importance = NotificationManager.IMPORTANCE_DEFAULT;
            NotificationChannel channel = new NotificationChannel(CHANNEL_ID, name, importance);
            channel.setDescription(description);
            // Register the channel with the system; you can't change the importance
            // or other notification behaviors after this
             notificationManager = getSystemService(NotificationManager.class);
            notificationManager.createNotificationChannel(channel);
        }
    }

然后在notificationBuilder上使用相同的notificationManager对象

  NotificationCompat.Builder builder = new NotificationCompat.Builder(this, CHANNEL_ID);

        builder.setContentIntent(pendingIntent)
                .setSmallIcon(R.drawable.ic_launcher)
               // .setLargeIcon(BitmapFactory.decodeResource(res, R.drawable.ic_launcher))
               // .setTicker(res.getString(R.string.notification_title))
                .setAutoCancel(true)
                .setContentTitle(res.getString(R.string.notification_title))
                .setContentText(res.getString(R.string.notification_subject));


        notificationManager.notify(NOTIFICATION_ID, builder.build());
        Log.i(TAG,"Notifications sent.");

---

您没有为通知设置通道，因此它不会显示在Oreo+设备上。我建议使用workManager而不是alarm manager和serviceYou's right@RobCo，它终于起作用了，我只需将通知通道添加到notificationManager