【Android 进程保活】提升进程优先级 ( 使用前台 Service 提高应用进程优先级 | 效果展示 | 源码资源 )（一）

package kim.hsl.keep_progress_alive.foreground_service;
import android.app.Notification;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.graphics.Color;
import android.os.Build;
import android.os.IBinder;
import androidx.annotation.RequiresApi;
import androidx.core.app.NotificationCompat;
import kim.hsl.keep_progress_alive.R;
import static androidx.core.app.NotificationCompat.PRIORITY_MIN;
public class ForegroundService extends Service {
    public ForegroundService() {
    }
    @Override
    public void onCreate() {
        super.onCreate();
        // 将该服务转为前台服务
        // 需要设置 ID 和 通知
        // 设置 ID 为 0 , 就不显示已通知了 , 但是 oom_adj 值会变成后台进程 11
        // 设置 ID 为 1 , 会在通知栏显示该前台服务
        //startForeground(1, new Notification());
        startForeground();
    }
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }
    /**
     * 启动前台服务
     */
    private void startForeground() {
        String channelId = null;
        // 8.0 以上需要特殊处理
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            channelId = createNotificationChannel("kim.hsl", "ForegroundService");
        } else {
            channelId = "";
        }
        NotificationCompat.Builder builder = new NotificationCompat.Builder(this, channelId);
        Notification notification = builder.setOngoing(true)
                .setSmallIcon(R.mipmap.ic_launcher)
                .setPriority(PRIORITY_MIN)
                .setCategory(Notification.CATEGORY_SERVICE)
                .build();
        startForeground(1, notification);
    }
    /**
     * 创建通知通道
     * @param channelId
     * @param channelName
     * @return
     */
    @RequiresApi(Build.VERSION_CODES.O)
    private String createNotificationChannel(String channelId, String channelName){
        NotificationChannel chan = new NotificationChannel(channelId,
                channelName, NotificationManager.IMPORTANCE_NONE);
        chan.setLightColor(Color.BLUE);
        chan.setLockscreenVisibility(Notification.VISIBILITY_PRIVATE);
        NotificationManager service = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        service.createNotificationChannel(chan);
        return channelId;
    }
}

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="kim.hsl.keep_progress_alive">
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.Keep_Progress_Alive">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <!--
            设置最近任务列表中不显示该 Activity 组件 ( 不要被用户察觉 )
            android:excludeFromRecents="true"
            设置 Activity 亲和性
            让该界面在一个独立的任务栈中 , 不要与本应用的其它任务栈放在一起
            避免解除锁屏后 , 关闭 1 像素界面 , 将整个任务栈都唤醒
            android:taskAffinity="kim.hsl.keep_progress_alive.alive"
        -->
        <activity
            android:name=".one_pixel_activity.OnePixelActivity"
            android:excludeFromRecents="true"
            android:taskAffinity="kim.hsl.keep_progress_alive.onepixel"
            android:theme="@style/OnePixelActivityTheme" />
        <!-- 用于提权的前台进程 -->
        <service
            android:name=".foreground_service.ForegroundService"
            android:enabled="true"
            android:exported="true"/>
    </application>
</manifest>

=package kim.hsl.keep_progress_alive;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import kim.hsl.keep_progress_alive.foreground_service.ForegroundService;
import kim.hsl.keep_progress_alive.one_pixel_activity.KeepProgressAliveManager;
public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // 1 像素 Activity 提升应用权限
        // 注册广播接收者 , 1 像素 Activity 启动的 广播接收者
        //KeepProgressAliveManager.getmInstance().registerReceiver(this);
        // 通过前台 Service 提升应用权限
        // 启动普通 Service , 但是在该 Service 的 onCreate 方法中执行了 startForeground
        // 变成了前台 Service 服务
        startService(new Intent(this, ForegroundService.class));
    }
    @Override
    protected void onDestroy() {
        super.onDestroy();
        // 取消注册广播接收者, 也可以不取消注册
        //KeepProgressAliveManager.getmInstance().registerReceiver(this);
    }
}