Asynctask与服务

Question

我正在使用Arduino和一个窗口传感器，因此我需要询问窗口是否关闭发送通知，15分钟后再次询问一小时。我的代码有问题，因为没有执行onPostExecute，因此不显示消息。希望你们可以帮助我，因为我的tesis。

代码：

public class ServicePush extends Service{     
private String windowstate, url;
private AsyncTask task;


public ServicePush() {

}

@Override
public IBinder onBind(Intent arg0) {
    // TODO Auto-generated method stub
    return null;
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    // TODO Auto-generated method stub
    SharedPreferences prefs = getSharedPreferences("Configuraciones", Context.MODE_PRIVATE);
    url = prefs.getString("IPArduinoYun", "10.40.4.3");
    url = "http://" + url + "/arduino/216";
    System.out.println("before first try");
    try {
        System.out.println("first try");
        GetArduinoData();
        Thread.sleep(15000);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }

    System.out.println("before while");

    while (windowstate != "Open"){
        try {
            System.out.println("While");
            GetArduinoData();
            Thread.sleep(15000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
    System.out.println("End");
    return START_STICKY;
}

public void GetArduinoData(){
    task = new ReadJSON().execute(url);
}

private class ReadJSON extends AsyncTask<String, Void, String> {    

    protected String doInBackground(String... urls) {
        System.out.println("doInBackground");
        return readJSONFeed(urls[0]);
    }

    protected void onPostExecute(String result) {
        try {
            JSONObject jsonObject = new JSONObject(result);
            windowstate = "";
            if (jsonObject.getString("Window").equals("0")) {
                windowstate = "Close";
                SendNotification();
            }
            if (jsonObject.getString("Window").equals("1")) {
                windowstate = "Open";
            }
            Toast.makeText(getBaseContext(), windowstate, Toast.LENGTH_SHORT).show();
            System.out.println("onPostExecute");
            task.cancel(true);
        } catch (Exception e) {
            Log.d("ReadJSON", e.getLocalizedMessage());
        }


    }
}

public String readJSONFeed(String URL) {       
    StringBuilder stringBuilder = new StringBuilder();
    HttpClient httpClient = new DefaultHttpClient();
    HttpGet httpGet = new HttpGet(URL);
    try {
        HttpResponse response = httpClient.execute(httpGet);
        StatusLine statusLine = response.getStatusLine();
        int statusCode = statusLine.getStatusCode();
        if (statusCode == 200) {
            HttpEntity entity = response.getEntity();
            InputStream inputStream = entity.getContent();
            BufferedReader reader = new BufferedReader(
                    new InputStreamReader(inputStream));
            String line;
            while ((line = reader.readLine()) != null) {
                stringBuilder.append(line);
            }
            inputStream.close();
        } else {
            Log.d("JSON", "Error downloading");
        }
    } catch (Exception e) {
        Log.d("readJSONFeed", e.getLocalizedMessage());
    }
    return stringBuilder.toString();
}

@Override
public void onDestroy() {
    // TODO Auto-generated method stub
    super.onDestroy();
    Toast.makeText(this, "Service destroyed", Toast.LENGTH_SHORT).show();
}

public void SendNotification(){
    Intent i = new Intent(this, MainActivity.class);
    PendingIntent pi = PendingIntent.getActivity(this, 0, i, 0);
    NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this)
            .setSmallIcon(R.drawable.ic_warning_black_24dp) 
            .setContentTitle("Recordatorio")    
            .setContentText("Debe abrir las ventanas para poder ventilar");  
    mBuilder.setContentIntent(pi);
    mBuilder.setDefaults(Notification.DEFAULT_SOUND);  
    mBuilder.setAutoCancel(true)
            .setVibrate(new long[]{1000, 1000, 1000, 1000, 1000});  
    NotificationManager mNotificationManager = (NotificationManager) this.getSystemService(Context.NOTIFICATION_SERVICE);
    mNotificationManager.notify(0, mBuilder.build());
}

Answer 1

所以..最后我找到了解决方案，我的教授在asynctask上使用sleep，并在onPostExecute中调用的新函数中使用了一个标志，创建了一个新的Asynctask.Hope这可以帮助需要它的人

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    // TODO Auto-generated method stub
    SharedPreferences prefs = getSharedPreferences("Configuraciones", Context.MODE_PRIVATE);
    url = prefs.getString("IPArduinoYun", "10.40.4.3");
    url = "http://" + url + "/arduino/216";

    GetArduinoData();
    return START_STICKY;
}

public void GetArduinoData(){
    new ReadJSON().execute(url);
}

public void GetDataReady(){
    if (windowstate != "Open"){
        //do something
    } else {
        //do something
    }
}

private class ReadJSON extends AsyncTask<String, Void, String> {    

    protected String doInBackground(String... urls) {
        try {
            Thread.sleep(10000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        return readJSONFeed(urls[0]);
    }

    protected void onPostExecute(String result) {
        try {
            JSONObject jsonObject = new JSONObject(result);
            windowstate = "";
            if (jsonObject.getString("Window").equals("0")) {
                windowstate = "Closed";
                SendNotification();
            }
            if (jsonObject.getString("Window").equals("1")) {
                windowstate = "Open";
            }
        } catch (Exception e) {
            Log.d("ReadJSON", e.getLocalizedMessage());
        }
        GetDataReady();
    }
}