Android后台服务

Android后台服务

随着Android版本不断更新,后台服务是越来越难存活了.

// MainActivity.java
public class MainActivity extends AppCompatActivity {
    private IncomingMessageHandler mHandler;
    /**
     * {@link Handler}允许您发送与线程相关联的消息。
     * 它也用于使开始和停止视图在短时间内闪烁。
     */
    private class IncomingMessageHandler extends Handler {
        // 使用弱引用防止内存泄露
        private WeakReference<MainActivity> mActivity;
        IncomingMessageHandler(MainActivity activity) {
            super(/* default looper */);
            this.mActivity = new WeakReference<>(activity);
        }
        @Override
        public void handleMessage(Message msg) {
            MainActivity mSchedulerAcitvity = mActivity.get();
            if (mSchedulerAcitvity == null) {
                return;
            }
            switch (msg.what) {
                case 0:
                    // msg.obj
                    break;
            }
        }
    }
    @Override
    protected void onStart() {
        super.onStart();
        // 启动服务并提供一种与此类通信的方法。
        mHandler = new IncomingMessageHandler(this);
        Intent startServiceIntent = new Intent(this, BTService.class);
        Messenger messengerIncoming = new Messenger(mHandler);
        startServiceIntent.putExtra(MESSENGER_INTENT_KEY, messengerIncoming);
        startService(startServiceIntent);
    }
}

// BTService.java
public class BTService extends Service {
    public static final String MESSENGER_INTENT_KEY = "MESSENGER_INTENT_KEY";
    private Messenger mActivityMessenger;
    private Handler handler;
    private void sendMessage(int messageID, Object params) {
        if (mActivityMessenger == null) {
            return;
        }
        Message m = Message.obtain();
        m.what = messageID;
        m.obj = params;
        try {
            mActivityMessenger.send(m);
        } catch (RemoteException e) {
            e.printStackTrace();
        }
    }
    private void fe() {
        String notifyId = "UA631";
        Notification.Builder builder = new Notification.Builder(this);
        NotificationManager manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        NotificationChannel mChannel = null;
        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
            mChannel = new NotificationChannel(notifyId, notifyId, NotificationManager.IMPORTANCE_HIGH);
            manager.createNotificationChannel(mChannel);
            builder = new Notification.Builder(this, notifyId);
        }
        builder.setTicker("uploadservice");
        builder.setContentText("请保持程序在后台运行");
        builder.setWhen(System.currentTimeMillis());
        Notification notification = builder.build();
        startForeground(1, notification);
    }
    @Override
    public void onDestroy() {
        MyLog.d("onDestroy ===== ");
        super.onDestroy();
        Intent startServiceIntent = new Intent(this, BTService.class);
        startServiceIntent.putExtra(MESSENGER_INTENT_KEY, mActivityMessenger);
        startService(startServiceIntent);
        stopForeground(true);
    }
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }
    @SuppressLint("HandlerLeak")
    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        if (intent != null) {
            mActivityMessenger = intent.getParcelableExtra(MESSENGER_INTENT_KEY);
        }
        MyLog.d("onStartCommand ===== ");
        fe();
        handler = new Handler() {
            @Override
            public void handleMessage(Message msg) {
                super.handleMessage(msg);
                if (msg.what == 0x10000) {
                    handler.sendEmptyMessageDelayed(0x10000, 40000);
                }
            }
        };
        handler.sendEmptyMessageDelayed(0x10000, 40000);
        return START_STICKY;
    }
}

<!-- AndroidManifest.xml -->
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.uascent.ua631">
    <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
    <application
        android:name=".MyApplication"
        android:allowBackup="true"
        android:icon="@drawable/logo"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".page.MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <action android:name="android.intent.action.VIEW" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <service android:name=".service.BTService" />
    </application>
</manifest>