Android PushNotification IntentService 并调用 AsyncTask 函数从服务器数据库获取数据并更新 sqlite 数据库

Posted 2023-05-07

【中文标题】Android PushNotification IntentService 并调用 AsyncTask 函数从服务器数据库获取数据并更新 sqlite 数据库

【英文标题】：Android PushNotification IntentService and call AsyncTask function to get Data from server database and update sqlite database

【发布时间】：2017-09-22 07:18:03

【问题描述】：

我正在使用 android 平台开发一个聊天应用程序。我要做的是当应用程序在 onHandleIntent() 函数中收到推送通知时。应用程序将调用 AsyncTask() 函数。 AsyncTask() 函数调用 php 服务器并从 PHP 服务器获取数据。接下来，我将获取数据并插入手机中的 SQLite 数据库。以下是我的代码：

public class GCMNotificationIntentService extends IntentService 

public static final int NOTIFICATION_ID = 1;
private NotificationManager mNotificationManager;
NotificationCompat.Builder builder;

public GCMNotificationIntentService() 
    super("GcmIntentService");


public static final String TAG = "GCMNotificationIntentService";

@Override
protected void onHandleIntent(Intent intent) 
    Bundle extras = intent.getExtras();
    GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(this);

    String messageType = gcm.getMessageType(intent);

    if (!extras.isEmpty()) 
        if (GoogleCloudMessaging.MESSAGE_TYPE_SEND_ERROR.equals(messageType)) 
            sendNotification("Send error: " + extras.toString());

         else if (GoogleCloudMessaging.MESSAGE_TYPE_DELETED.equals(messageType)) 
            sendNotification("Deleted messages on server: " + extras.toString());

         else if (GoogleCloudMessaging.MESSAGE_TYPE_MESSAGE.equals(messageType)) 

            for (int i = 0; i < 3; i++) 
                Log.i(TAG, "Working... " + (i + 1) + "/5 @ " + SystemClock.elapsedRealtime());
                try 
                    Thread.sleep(5000);
                 catch (InterruptedException e) 
                
            
            Log.i(TAG, "Completed work @ " + SystemClock.elapsedRealtime());
            sendNotification("Message Received from Google GCM Server: " + extras.getString("message"));
            Log.i(TAG, "Received: " + extras.toString());
            new GetContacts().execute();
        
    
    GcmBroadcastReceiver.completeWakefulIntent(intent);


private void sendNotification(String msg) 
    Log.d(TAG, "Preparing to send notification...: " + msg);
    mNotificationManager = (NotificationManager) this.getSystemService(Context.NOTIFICATION_SERVICE);

    PendingIntent contentIntent = PendingIntent.getActivity(this, 0, new Intent(this, MainActivity.class), 0);

    NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this).setSmallIcon(R.drawable.gcm_logo)
            .setContentTitle("GCM Notification")
            .setStyle(new NotificationCompat.BigTextStyle().bigText(msg))
            .setContentText(msg);

    mBuilder.setContentIntent(contentIntent);
    mNotificationManager.notify(NOTIFICATION_ID, mBuilder.build());
    Log.d(TAG, "Notification sent successfully.");



private class GetContacts extends AsyncTask<Void, Void, Void> 
    @Override
    protected void onPreExecute() 
        super.onPreExecute();
    

    @Override
    protected Void doInBackground(Void... arg0) 
        HttpHandler sh = new HttpHandler();
        String url = "http://131.4.44.69/JSON/index.php";
        String jsonStr = sh.makeServiceCall(url);

        if (jsonStr != null) 
            try 
                JSONObject jsonObj = new JSONObject(jsonStr);
                JSONArray contacts = jsonObj.getJSONArray("contacts");

                for (int i = 0; i < contacts.length(); i++) 
                    JSONObject c = contacts.getJSONObject(i);
                    String id = c.getString("id");
                    String name = c.getString("name");
                    String email = c.getString("email");
                    String address = c.getString("address");
                    String gender = c.getString("gender");

                    JSONObject phone = c.getJSONObject("phone");
                    String mobile = phone.getString("mobile");
                    String home = phone.getString("home");
                    String office = phone.getString("office");

                    HashMap<String, String> contact = new HashMap<>();
                    contact.put("id", id);
                    contact.put("name", name);
                    contact.put("email", email);
                    contact.put("mobile", mobile);

                
             catch (JSONException e) 
                e.printStackTrace();
            

        

        return null;
    

    @Override
    protected void onPostExecute(Void result) 
        super.onPostExecute(result);
    

但问题是我无法在 IntentService 类中调用 AsyncTask()。我该如何解决这个问题？

【问题讨论】：

为什么你在这里使用 asyncTask，onHandleIntent 已经在后台线程中执行了。

【参考方案1】：

Intent 服务已在后台线程中运行，您无需在其中调用任何异步任务。您可以直接在 onHandleIntent() 方法中点击 api，因为它已经在后台线程中

【讨论】：

这意味着我可以在 IntentService 函数中执行 HttpURLConnection 吗？

是的，你可以直接在 IntentService 中做 httpUrlConnection

@Ashrif Ahamad 谢谢，我明白了