App: Socket in Async Task

MobileApp/app/src/main/java/com/example/lfrmobileapp/Communication.java

 import java.util.Objects;
 
 public class Communication {
-    public boolean sendData(String data, String ip, int port) {
-        try {
-            Socket socket = new Socket(ip, port);
-            DataOutputStream DOS = new DataOutputStream(socket.getOutputStream());
-            DOS.writeUTF(data);
-            socket.close();
-        } catch (Exception e) {
-            e.printStackTrace();
-            return true; //ToDo: change to false to test connection - currently always true is delivered
-        }
-        return true;
-    }
-
     public String telegram(int[] wheels, int strenght){
         String tel = "";
-        tel += "0;"; //Manuel mode
+        tel += "0"; //Manuel mode
 
         for(int i = 0; i < wheels.length; i++){
             if(wheels[i] == 1){
-                tel += Float.toString(((float)strenght)/100) + ";";
+                tel += ";" + Float.toString(((float)strenght)/100)  ;
             }else if(wheels[i] == -1)
-                tel += Float.toString(((float)-strenght)/100) + ";";
+                tel += ";" + Float.toString(((float)-strenght)/100);
             else{
-                tel += "0.00;";
+                tel += ";0.00";
             }
         }
-        Log.v("TAG", tel + "\n");
         return tel;
     }
 
     public String telegram(boolean startStop, ArrayList<String> list){
         String tel = "";
-        tel += "1;"; //Autonomous mode
+        tel += "1"; //Autonomous mode
         if(startStop){
-            tel += "1;";
+            tel += ";1";
         }else{
-            tel += "0;";
+            tel += ";0";
         }
 
         for (String i : list) {
             if(i.equals("Links")){
-                tel += "0;";
+                tel += ";0";
             }else if (i.equals("Rechts")){
-                tel += "1;";
+                tel += ";1";
             }
         }
-        Log.v("TAG", tel + "\n");
         return tel;
     }
+
 }

MobileApp/app/src/main/java/com/example/lfrmobileapp/DataTransferAsyncTask.java

 package com.example.lfrmobileapp;
 
 import android.os.AsyncTask;
+import android.util.Log;
 
+import java.io.DataOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.net.Socket;
 
-private class DataTransferAsyncTask extends AsyncTask<Void, Void, Void> {
-    private static final int sendRatePerSecond = 2;
-    private String hostname;
+public class DataTransferAsyncTask extends AsyncTask<Void, Void, Void> {
+    private static final int sendRatePerSecond = 4;
+    private String ipAdress;
     private int portNumber;
-    DataTransferAsyncTask(String hostname, int portNumber) {
-        this.hostname = hostname;
+    private String telegram;
+    private boolean connected;
+
+    public DataTransferAsyncTask(String ipAdress, int portNumber) {
+        this.ipAdress = ipAdress;
         this.portNumber = portNumber;
+        this.telegram = "";
+        this.connected = false;
+    }
+
+    public void writeTelegram(String telegram) {
+        this.telegram = telegram;
     }
+
     @Override
     protected Void doInBackground(Void... params) {
-        try {
-            Socket socket = new Socket(hostname, portNumber);
-            OutputStream outputStream = socket.getOutputStream();
-            while (!isCancelled()) { 
-                outputStream.write("data".getBytes());
-                outputStream.flush();
-                Thread.sleep(1000 / sendRatePerSecond);
+        while(!isCancelled()) {
+            try {
+                Socket socket = new Socket(ipAdress, portNumber);
+                DataOutputStream outputStream = new DataOutputStream(socket.getOutputStream());
+                connected = true;
+                while (!isCancelled() && telegram.length() > 0) {
+                    Log.v("TAG", telegram + "\n");
+                    outputStream.writeBytes(telegram);
+                    outputStream.flush();
+                    Thread.sleep(1000 / sendRatePerSecond);
+                }
+                socket.close();
+            } catch (Exception e) {
+                e.printStackTrace();
+                connected = false;
             }
-            socket.close();
-        } catch (IOException | InterruptedException e) {
-            e.printStackTrace();
         }
         return null;
     }
+
+
+    public boolean getConnectionState(){
+        return connected;
+    }
 }

MobileApp/app/src/main/java/com/example/lfrmobileapp/ui/dashboard/DashboardFragment.java

 import androidx.lifecycle.ViewModelProvider;
 
 import com.example.lfrmobileapp.Communication;
+import com.example.lfrmobileapp.DataTransferAsyncTask;
 import com.example.lfrmobileapp.R;
 import com.example.lfrmobileapp.databinding.FragmentAutomatikBinding;
 
     //Keys for Shared Preferences
     String listKey = "listkey";
 
+    DataTransferAsyncTask dataTransferAsyncTask;
+
     public View onCreateView(@NonNull LayoutInflater inflater,
                              ViewGroup container, Bundle savedInstanceState) {
         DashboardViewModel dashboardViewModel =
         ipAddress = sharedPref.getString(ipKey, "");
         port = sharedPref.getInt(portKey, -1);
 
+        dataTransferAsyncTask = new DataTransferAsyncTask(ipAddress, port);
+        dataTransferAsyncTask.execute();
+
         binding.startAutomatic.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
 
             @Override
             public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                 if(isChecked){
-                    com.sendData(com.telegram(true, autoList), ipAddress, port);
+                    dataTransferAsyncTask.writeTelegram(com.telegram(true, autoList));
                 }else{
-                    com.sendData(com.telegram(false, autoList), ipAddress, port);
+                    dataTransferAsyncTask.writeTelegram(com.telegram(false, autoList));
                 }
             }
         });
     @Override
     public void onDestroyView() {
         super.onDestroyView();
+        dataTransferAsyncTask.cancel(false);
         binding = null;
     }
 

MobileApp/app/src/main/java/com/example/lfrmobileapp/ui/home/HomeFragment.java

 package com.example.lfrmobileapp.ui.home;
 
+import android.annotation.SuppressLint;
 import android.content.Context;
 import android.content.SharedPreferences;
 import android.os.Bundle;
 import android.view.LayoutInflater;
+import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.Button;
 import androidx.lifecycle.ViewModelProvider;
 
 import com.example.lfrmobileapp.Communication;
+import com.example.lfrmobileapp.DataTransferAsyncTask;
 import com.example.lfrmobileapp.R;
 import com.example.lfrmobileapp.databinding.FragmentManuellBinding;
 import com.example.lfrmobileapp.ui.notifications.NotificationsFragment;
     int port = 8000;
 
     Communication com = new Communication();
+    DataTransferAsyncTask dataTransferAsyncTask;
 
     private FragmentManuellBinding binding;
 
         final TextView textView = binding.textHome;
         homeViewModel.getText().observe(getViewLifecycleOwner(), textView::setText);
 
-        binding.rotateLeft.setOnClickListener(new View.OnClickListener(){
+        dataTransferAsyncTask = new DataTransferAsyncTask(ipAddress, port);
+        dataTransferAsyncTask.execute();
+
+        binding.rotateLeft.setOnTouchListener(new View.OnTouchListener(){
+            @SuppressLint("ClickableViewAccessibility")
             @Override
-            public void onClick(View v){
-                com.sendData(com.telegram(new int[]{-1, 1, -1, 1}, 100), ipAddress, port);
-            };
-        });
+                public boolean onTouch(View v, MotionEvent event) {
+
+                    if(event.getAction() == MotionEvent.ACTION_UP){
+                        binding.rotateLeft.performClick();
+                        dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{0, 0, 0, 0}, 0));
+                        return true;
+                    }else{
+                        dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{-1, 1, -1, 1}, 100));
+                    }
+                    return false;
+                }
+            });
 
-        binding.rotateRight.setOnClickListener(new View.OnClickListener(){
+        binding.rotateRight.setOnTouchListener(new View.OnTouchListener(){
+            @SuppressLint("ClickableViewAccessibility")
             @Override
-            public void onClick(View v){
-                com.sendData(com.telegram(new int[]{1, -1, 1, -1}, 100), ipAddress, port);
-            };
+            public boolean onTouch(View v, MotionEvent event) {
+
+                if(event.getAction() == MotionEvent.ACTION_UP){
+                    binding.rotateRight.performClick();
+                    dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{0, 0, 0, 0}, 0));
+                    return true;
+                }else{
+                    dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{1, -1, 1, -1}, 100));
+                }
+                return false;
+            }
         });
 
+
         JoystickView joystick = (JoystickView) binding.joystick;
         joystick.setOnMoveListener(new JoystickView.OnMoveListener() {
             @Override
                 //8 segments of the joystick
                 if((angle >= 338 || angle < 22) && strength != 0){
                     joystick.setBackgroundResource(R.mipmap.right);
-                    com.sendData(com.telegram(new int[]{1, -1, -1, 1}, strength), ipAddress, port);
+                    dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{1, -1, -1, 1}, strength));
                 }else if((angle >= 22 && angle < 67) && strength != 0){
                     joystick.setBackgroundResource(R.mipmap.right_forward);
-                    com.sendData(com.telegram(new int[]{1, 0, 0, 1}, strength), ipAddress, port);
+                    dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{1, 0, 0, 1}, strength));
                 }else if((angle >=67 && angle < 112) && strength != 0){
                     joystick.setBackgroundResource(R.mipmap.forward);
-                    com.sendData(com.telegram(new int[]{1, 1, 1, 1}, strength), ipAddress, port);
+                    dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{1, 1, 1, 1}, strength));
                 }else if((angle >=112 && angle < 157) && strength != 0){
                     joystick.setBackgroundResource(R.mipmap.left_forward);
-                    com.sendData(com.telegram(new int[]{0, 1, 1, 0}, strength), ipAddress, port);
+                    dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{0, 1, 1, 0}, strength));
                 }else if((angle >=157 && angle < 202) && strength != 0){
                     joystick.setBackgroundResource(R.mipmap.left);
-                    com.sendData(com.telegram(new int[]{-1, 1, 1, -1}, strength), ipAddress, port);
+                    dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{-1, 1, 1, -1}, strength));
                 }else if((angle >=202 && angle < 247) && strength != 0){
                     joystick.setBackgroundResource(R.mipmap.left_back);
-                    com.sendData(com.telegram(new int[]{-1, 0, 0, -1}, strength), ipAddress, port);
+                    dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{-1, 0, 0, -1}, strength));
                 }else if((angle >=247 && angle < 292) && strength != 0){
                     joystick.setBackgroundResource(R.mipmap.back);
-                    com.sendData(com.telegram(new int[]{-1, -1, -1, -1}, strength), ipAddress, port);
+                    dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{-1, -1, -1, -1}, strength));
                 }else if((angle >=292 && angle < 337) && strength != 0){
                     joystick.setBackgroundResource(R.mipmap.right_back);
-                    com.sendData(com.telegram(new int[]{0, -1, -1, 0}, strength), ipAddress, port);
+                    dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{0, -1, -1, 0}, strength));
                 }
                 else{
                     joystick.setBackgroundResource(R.mipmap.blank);
-                    com.sendData(com.telegram(new int[]{0, 0, 0, 0}, strength), ipAddress, port);
+                    dataTransferAsyncTask.writeTelegram(com.telegram(new int[]{0, 0, 0, 0}, strength));
                 }
             }
         });
     @Override
     public void onDestroyView() {
         super.onDestroyView();
+        dataTransferAsyncTask.cancel(false);
         binding = null;
     }
 }

MobileApp/app/src/main/java/com/example/lfrmobileapp/ui/notifications/NotificationsFragment.java

 import androidx.lifecycle.ViewModelProvider;
 
 import com.example.lfrmobileapp.Communication;
+import com.example.lfrmobileapp.DataTransferAsyncTask;
 import com.example.lfrmobileapp.R;
 import com.example.lfrmobileapp.databinding.FragmentEinstellungenBinding;
 
 
 public class NotificationsFragment extends Fragment {
 
+    Boolean connected = false;
+
     String ipKey = "ipkey";
     String portKey = "portkey";
     String connectionFailed = "Verbindung fehlgeschlagen.";
     int port = 8000;
 
     int duration = Toast.LENGTH_LONG;
+    DataTransferAsyncTask dataTransferAsyncTask;
 
     private FragmentEinstellungenBinding binding;
 
             binding.port.setText("");
         }
 
+        dataTransferAsyncTask = new DataTransferAsyncTask(ipAddress, port);
+
+
 
         final Button button = binding.connect;
         button.setOnClickListener(new View.OnClickListener() {
             public void onClick(View v) {
                 ipAddress = String.valueOf(binding.ipAdress.getText());
                 port = Integer.parseInt(String.valueOf(binding.port.getText()));
-                if(com.sendData("", ipAddress, port)){
+
+                dataTransferAsyncTask = new DataTransferAsyncTask(ipAddress, port);
+                dataTransferAsyncTask.writeTelegram("Verbindung aufbauen");
+                dataTransferAsyncTask.execute();
+
+                if(dataTransferAsyncTask.getConnectionState()){
                     editor.putString(ipKey, ipAddress);
                     editor.putInt(portKey, port);
                     editor.apply();
                 }else{
                     Toast toast = Toast.makeText(v.getContext(), connectionFailed, duration);
                     toast.show();
+                    dataTransferAsyncTask.cancel(true);
                 }
             }
         });
 
-
         return root;
     }
 
     @Override
     public void onDestroyView() {
         super.onDestroyView();
+        dataTransferAsyncTask.cancel(true);
         binding = null;
     }
 }

MobileApp/app/src/main/res/layout/fragment_automatik.xml

 
     <ListView
         android:id="@+id/automaticList"
-        android:layout_width="413dp"
+        android:layout_width="match_parent"
         android:layout_height="470dp"
         android:layout_marginTop="110dp"
         app:layout_constraintEnd_toEndOf="parent"