如何在Android中處理套接字事件作爲後臺服務？

Question

我是新來的Android開發人員，我希望我的應用程序能夠檢測套接字事件，即使應用程序未通過後臺服務活動（所以我可以推送通知，例如，如果有一個新的消息， Whatsapp和其他人這樣做）。

我實現了後臺服務和啓動服務的應用程序類，但堅持在哪裏以及如何將套接字事件作爲Runnable任務放入我的後臺服務中。

我修改了下面的socket.io android chat項目示例，並添加了服務和應用程序類。

ChatApplication.java

package com.github.nkzawa.socketio.androidchat; 

import android.app.Application; 
import android.content.Intent; 
import android.content.res.Configuration; 

import io.socket.client.IO; 
import io.socket.client.Socket; 

import java.net.URISyntaxException; 

public class ChatApplication extends Application { 

    @Override 
    // called when the application is starting, before any other application objects have been created 
    public void onCreate() { 
     super.onCreate(); 

     // represents our background service 
     Intent background = new Intent(this, SocketBackgroundService.class); 
     startService(background); 
    } 

    private Socket mSocket; 
    { 
     try { 
      mSocket = IO.socket(Constants.CHAT_SERVER_URL); 
     } catch (URISyntaxException e) { 
      throw new RuntimeException(e); 
     } 
    } 

    public Socket getSocket() { 
     return mSocket; 
    } 
} 

SocketBackgroundService.java

package com.github.nkzawa.socketio.androidchat; 

import android.app.Service; 
import android.content.Intent; 
import android.os.IBinder; 
import android.util.Log; 

public class SocketBackgroundService extends Service { 
    private boolean isRunning; 
    private Thread backgroundThread; 

    @Override 
    public IBinder onBind(Intent intent) { 
     return null; 
    } 

    @Override 
    public void onCreate() { 
     this.isRunning = false; 
     this.backgroundThread = new Thread(myTask); 
    } 

    private Runnable myTask = new Runnable() { 
     @Override 
     public void run() { 
      // do something in here 
      Log.i("INFO", "SOCKET BACKGROUND SERVICE IS RUNNING"); 

      //TODO - how to handle socket events here? 
      //How do I do something like mSocket.on(Socket.EVENT_CONNECT,onConnect); here? 
     } 
    }; 

    @Override 
    public void onDestroy() { 
     this.isRunning = false; 
    } 

    @Override 
    public int onStartCommand(Intent intent, int flags, int startId) { 
     if(!this.isRunning) { 
      this.isRunning = true; 
      this.backgroundThread.start(); 
     } 

     return START_STICKY; 
    } 
} 

Answer 1

如果您需要的插座是活着你的應用程序停止後。將套接字移動到後臺服務，然後您可以在服務中添加套接字事件。

Answer 2

您在主線程上打開套接字。不要在主線程上打開套接字連接，它會爲您提供ANR（應用程序無響應）錯誤，這是由於UI線程上大量繁重工作而發生的。它阻止UI線程超過5秒。所以我建議你在服務線程中打開套接字連接。
下面是使用普通的插座例如：

1. 對背景服務開始線程
2. 用來打開在螺紋插座連接

3. 用於套接字通信

   創建單獨的類上創建線程類創建一個服務類

   public class SocketBackgroundService extends Service { 
   
   private SocketThread mSocketThread; 
   
   @Override 
   public IBinder onBind(Intent intent) { 
       return null; 
   } 
   
   @Override 
   public void onCreate() { 
   
       mSocketThread = SocketThread.getInstance(); 
   } 
   
   
   @Override 
   public void onDestroy() { 
       //stop thread and socket connection here 
   } 
   
   @Override 
   public int onStartCommand(Intent intent, int flags, int startId) { 
       if (mSocketThread.startThread) { 
       } else { 
        stopSelf(); 
       } 
   
       return START_STICKY; 
   } 
   } 
   
   public class SocketThread extends Thread { 
   
   private static SocketThread mSocketThread; 
   private SocketClient mSocketClient; 
   
   private SocketThread() { 
   } 
   
   // create single instance of socket thread class 
   public static SocketThread getInstance() { 
       if (mSocketThread == null)//you can use synchronized also 
       { 
        mSocketThread = new SocketThread(); 
       } 
       return mSocketThread; 
   } 
   
   
   public boolean startThread() { 
         =new SocketClient(); 
       if (socketClient.isConnected()) { 
        mSocketThread.start() 
        return true; 
       } 
       return false; 
   } 
   
   @Override 
   public void run() { 
       super.run(); 
       while (mSocketClient.isConnected()) { 
        // continue listen 
       } 
       // otherwise remove socketClient instance and stop thread 
   } 
   
   public class SocketClient { 
       //write all code here regarding opening, closing sockets 
       //create constructor 
       public SocketClient() { 
        // open socket connection here 
       } 
   
       public boolean isConnected() { 
        return true; 
       } 
   }