android - 前台服务在 Oreo 上被杀死

Question

我正在为我的前台服务而苦苦挣扎。在我的设备(Redmi 5 Plus，Android 8.1.0)上，服务通知不再可见应用程序已从最近的应用程序中删除。在其他设备(Android 5.0.1、Android 7.0)和模拟器(android 8.1 - api 27)上，当应用从最近的应用中删除时，通知仍然可见。

在主 Activity 中，我正在使用 ContextCompat.startForegroundService(this, intent) 来启动我的服务。

前台服务代码如下:

package com.ngallazzi.bluetoothtests.services

import android.annotation.SuppressLint
import android.annotation.TargetApi
import android.app.*
import android.content.Context
import android.content.Intent
import android.os.Build
import android.os.IBinder
import android.support.v4.app.NotificationCompat
import android.support.v4.app.NotificationCompat.PRIORITY_LOW
import android.util.Log
import com.ngallazzi.blemanager.managers.DeviceScanningListener
import com.ngallazzi.blemanager.managers.InRangeDetectionManager
import com.ngallazzi.bluetoothtests.MainActivity
import com.polidea.rxandroidble2.RxBleDevice


/**
 * BluetoothTests
 * Created by Nicola on 12/17/2018.
 * Copyright © 2018 Zehus. All rights reserved.
 */

class DeviceDetectionService : Service() {

    private lateinit var detectionManager: InRangeDetectionManager

    override fun onBind(intent: Intent): IBinder? {
        // We don't provide binding, so return null
        return null
    }

    override fun onCreate() {
        super.onCreate()
        detectionManager = InRangeDetectionManager(this)
    }

    @SuppressLint("MissingPermission")
    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
        if (intent != null) {
            val action = intent.action

            when (action) {
                ACTION_START_FOREGROUND_SERVICE -> {
                    startForegroundService()
                    detectionManager.startDeviceScanning(object : DeviceScanningListener {
                        @SuppressLint("CheckResult")
                        override fun onDeviceFound(device: RxBleDevice) {
                            device.establishConnection(false).subscribe({
                                Log.v(TAG, "Connected")
                                displayNotification(getNotification("Connected with: {${device.name}}"))
                            }, {
                                displayNotification(getNotification("An error occurred: {$it.message!!}"))
                            })
                        }

                        override fun onError(message: String?) {
                            displayNotification(getNotification("An error occurred: {$message}"))
                        }

                    })
                }
                ACTION_STOP_FOREGROUND_SERVICE -> {
                    stopForegroundService()
                }
            }

        }
        return START_NOT_STICKY
    }

    @SuppressLint("MissingPermission")
    private fun startForegroundService() {
        startForeground(NOTIFICATION_ID, getNotification(SEARCHING_DEVICES_MESSAGE))
        Log.v(TAG, "Device detection service started")
    }

    private fun getNotification(message: String): Notification {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
            createChannel()

        val mBuilder = NotificationCompat.Builder(this, CHANNEL_NAME).apply {
            setSmallIcon(android.R.drawable.ic_menu_mylocation)
            setContentTitle(message)
            setContentIntent(getMainActivityPendingIntent())
        }

        return mBuilder
            .setPriority(PRIORITY_LOW)
            .setCategory(Notification.CATEGORY_SERVICE)
            .build()
    }

    private fun displayNotification(notification: Notification) {
        val mNotificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
        mNotificationManager.notify(NOTIFICATION_ID, notification)
    }

    private fun getMainActivityPendingIntent(): PendingIntent {
        // Create an Intent for the activity you want to start
        val intent = Intent(this, MainActivity::class.java)
        // Create the TaskStackBuilder
        val pendingIntent = PendingIntent.getActivity(
            this, 0,
            intent, PendingIntent.FLAG_UPDATE_CURRENT
        );
        return pendingIntent!!
    }

    @TargetApi(26)
    @Synchronized
    private fun createChannel() {
        val mNotificationManager = this.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager

        val importance = NotificationManager.IMPORTANCE_DEFAULT

        val mChannel = NotificationChannel(CHANNEL_NAME, SEARCHING_DEVICES_MESSAGE, importance)

        mNotificationManager.createNotificationChannel(mChannel)
    }

    private fun stopForegroundService() {
        Log.d(TAG, "Stop foreground service.")

        // Stop foreground service and remove the notification.
        stopForeground(true)

        // Stop the foreground service.
        stopSelf()
    }


    override fun onDestroy() {
        super.onDestroy()

    }

    companion object {
        private val TAG = DeviceDetectionService::class.java.simpleName

        const val NOTIFICATION_ID = 1
        const val ACTION_START_FOREGROUND_SERVICE = "start_service"
        const val ACTION_STOP_FOREGROUND_SERVICE = "stop_service"
        const val CHANNEL_NAME = "DEVICE_DETECTION_SERVICE"
        const val SEARCHING_DEVICES_MESSAGE = "Searching in range device"
    }
}

这是我的 list 文件:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.ngallazzi.bluetoothtests">

    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE"/>
    <uses-permission android:name="android.permission.INTERNET"/>

    <application
            android:allowBackup="true"
            android:name=".App"
            android:icon="@mipmap/ic_launcher"
            android:label="@string/app_name"
            android:roundIcon="@mipmap/ic_launcher_round"
            android:supportsRtl="true"
            android:theme="@style/AppTheme">
        <activity android:name=".MainActivity" android:launchMode="singleInstance">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>

                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
        <service android:name=".services.DeviceDetectionService" android:enabled="true"/>

        <receiver android:name=".BootCompletedReceiver" android:enabled="true" android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED"/>
                <action android:name="android.intent.action.REBOOT"/>
                <action android:name="android.intent.action.QUICKBOOT_POWERON"/>
            </intent-filter>
        </receiver>

    </application>

</manifest>

我错过了什么？它是否受后台执行限制的约束？

Answer 1

试试这个

Step 1) Add this tag android:process in your service class tag inandroid:process="classname"manifest file

然后在服务类中执行此操作

Step 2) Override onTaskRemoved() in service class

Restart the service using alarm manager

Step 3) Ask user to enable autorun persmission which has customized os

如果用户启用它，那么您的服务将在应用被终止后运行。

Link for autoenable permission code

注意:- 复制并粘贴这段代码，Kotlin 转换器会自动转换它