Question

I have the following code to run a client socket connection in a asynctask:

@Override
protected Boolean doInBackground(Void... params) { //This runs on a different thread
    boolean result = false;
    try {
        Log.i("AsyncTask", "doInBackground: Creating socket");
        SocketAddress sockaddr = new InetSocketAddress("192.168.1.115", 9090);
        nsocket = new Socket();
        nsocket.connect(sockaddr, 5000); //10 second connection timeout
        if (nsocket.isConnected()) { 
            nis = nsocket.getInputStream();
            wr = new BufferedWriter(new OutputStreamWriter(nsocket.getOutputStream()));
            Log.i("AsyncTask", "doInBackground: Socket created, streams assigned");
            Log.i("AsyncTask", "doInBackground: Waiting for inital data...");
            sockState = true;
            byte[] buffer = new byte[4096];
            int read = nis.read(buffer, 0, 4096); //This is blocking
            while(read != -1){
                byte[] tempdata = new byte[read];
                System.arraycopy(buffer, 0, tempdata, 0, read);
                publishProgress(tempdata);
                Log.i("AsyncTask", "doInBackground: Got some data");
                read = nis.read(buffer, 0, 4096); //This is blocking
            }
        }
    } catch (IOException e) {
        e.printStackTrace();
        Log.i("AsyncTask", "doInBackground: IOException");
        result = true;
    } catch (Exception e) {
        e.printStackTrace();
        Log.i("AsyncTask", "doInBackground: Exception");
        result = true;
    } finally {
        try {
            nis.close();
            wr.close();
            nsocket.close();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
        Log.i("AsyncTask", "doInBackground: Finished");
    }
    return result;
}

@Override
protected void onProgressUpdate(byte[]... values) {
     Log.d("KMC.NetworkTask", String.valueOf(values[0]));
    if (values.length > 0) {
        Log.d("KMC.NetworkTask", "onProgressUpdate: " + values[0].length + " bytes received.");
        result = new String(values[0]);
    }
}

THe socket does work. However, onProgressUpdate is not called, even though the background task tells me data came in.

Anyone got some pointers for me?? I couldn’t find anything on google 😐

Answer 1

For now i solved it like this:

@Override
protected Boolean doInBackground(Void... params) { //This runs on a different thread
    try {
        Log.i("AsyncTask", "doInBackground: Creating socket");
        SocketAddress sockaddr = new InetSocketAddress("192.168.1.115", 9090);
        nsocket = new Socket();
        nsocket.connect(sockaddr, 5000); //10 second connection timeout
        if (nsocket.isConnected()) { 

            in = new BufferedReader(new InputStreamReader(nsocket.getInputStream()));
            wr = new BufferedWriter(new OutputStreamWriter(nsocket.getOutputStream()));
            Log.i("AsyncTask", "doInBackground: Socket created, streams assigned");
            sockState = true;

            String inputLine = "";
            while ((inputLine = in.readLine()) != null) {
                result = inputLine;
                Log.d("AsyncTask", "doInBackground: Got some data:" + inputLine);
            }
        }
    } catch (IOException e) {
        e.printStackTrace();
        Log.i("AsyncTask", "doInBackground: IOException");
    } catch (Exception e) {
        e.printStackTrace();
        Log.i("AsyncTask", "doInBackground: Exception");
    } finally {
        try {
            nis.close();
            wr.close();
            nsocket.close();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
        Log.i("AsyncTask", "doInBackground: Finished");
    }
    return true;
}

public String getResult(){
    String r = result;
    result = null;
    return r;
}

The main thread waits for the result, and then retrieves the result with getResult():

while(null == networktask.result){}
Log.d("KMC.onCreate", networktask.getResult());