Kommunikation Version 1.1 UDP Socket

app/src/main/java/com/example/ueberwachungssystem/MainActivity.java

 import android.net.wifi.WifiInfo;
 import android.net.wifi.WifiManager;
 import android.os.Bundle;
+import android.provider.Settings;
+import android.telephony.TelephonyManager;
 import android.view.View;
 import android.widget.Button;
 import android.widget.EditText;
 
     String message = "";
 
+    String deviceId;
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         tvMessages = findViewById(R.id.tvMessages);
         tvConnectionInfos = findViewById(R.id.tvConnectionInfos);
+        String deviceId = Settings.Secure.getString(getContentResolver(), Settings.Secure.ANDROID_ID);
         try {
             SERVER_IP = getLocalIpAddress();
             tvConnectionInfos.setText("Connection Infos: \n Own IP-Adress: " + SERVER_IP+ " Port: " + SERVER_PORT);
             @Override
             public void onClick(View v) {
                 i++;
-                communication.sendTrue("Test" +i);
+                communication.sendTrue(deviceId+ "Test" +i);
             }
         });
     }
     protected void onResume() {
         super.onResume();
         communication = new WifiCommunication(MainActivity.this, SERVER_PORT);
+        //communication.sendTrue(deviceId+ " has Entered");
 
     }
     @Override

app/src/main/java/com/example/ueberwachungssystem/WifiCommunication.java

         try {
             socket = new DatagramSocket(this.port);
             socket.setBroadcast(true);
-            address = InetAddress.getByName("255.255.255.255");
+            address = InetAddress.getByName("10.0.2.255"); //100.82.255.255
             running = true;
             send = false;
             new ReceiveThread().start();
     }
     private class ReceiveThread extends Thread {
         private StringBuffer rxStringBuffer = new StringBuffer();
-        private String rxString;
+        private String rxString="";
         private String previousRxString = "";
+
         @Override
         public void run() {
             try {
                 do {
-                    byte[] rxBuffer = new byte[512];
+                    byte[] receiveData = new byte[512];
                     InetAddress fromAdress;
                     int fromPort;
-                    DatagramPacket rxPacket = new DatagramPacket(rxBuffer, rxBuffer.length);
+                    DatagramPacket rxPacket = new DatagramPacket(receiveData, receiveData.length);
                     socket.receive(rxPacket);
                     fromAdress = rxPacket.getAddress();
                     fromPort = rxPacket.getPort();
-                    rxString = new String(rxBuffer, 0, rxPacket.getLength());
+                    rxString = new String(rxPacket.getData());
                     if(!previousRxString.equals(rxString)) {
+                        rxStringBuffer.append(rxString).append("\n");
                         mainActivity.runOnUiThread(() -> mainActivity.tvMessages.setText(rxStringBuffer));
-                        rxStringBuffer.append("Adress: " + fromAdress).append(" Port: " + fromPort).append(" Message " +rxString).append("\n");
+                        previousRxString = rxString;
                     }
-                    previousRxString = rxString;
+
 
                 } while (running);
             }
                     if(send)
                     {
                         send = false;
+                        byte[] send_Data = new byte[512];
+                        String txString = (getLocalIpAddress() + " sends:" +messageToSend+ " Count: " + tmpCnt++);
+                        send_Data = txString.getBytes();
 
-                        String txString = getLocalIpAddress() + " sends:" +messageToSend+ " Count: " + tmpCnt++;
-                        byte[] txBuffer = txString.getBytes();
-
-                        DatagramPacket txPacket = new DatagramPacket(txBuffer, txBuffer.length, address, port);
+                        DatagramPacket txPacket = new DatagramPacket(send_Data, txString.length(), address, port);
 
-                        for(int i = 0; i < 20; i++) {
+                        for(int i = 0; i < 500; i++) {
                             socket.send(txPacket);
+                            /*try{
+                                sleep(10);
+                            }catch (InterruptedException e){
+                                e.printStackTrace();
+                            }*/
                         }
                     }
                 } while (running);

app/src/main/res/layout/activity_main.xml

         android:layout_width = "match_parent"
         android:layout_height = "wrap_content"
         android:inputType = "textMultiLine"
-        android:textAppearance = "@style/Base.TextAppearance.AppCompat.Medium" />
-    <TextView
-        android:id = "@+id/tvMessages"
-        android:layout_width = "match_parent"
-        android:layout_height = "wrap_content"
-        android:layout_below="@id/tvConnectionInfos"
-        android:inputType = "textMultiLine"
+        android:hint="ConnectionInfos"
         android:textAppearance = "@style/Base.TextAppearance.AppCompat.Medium" />
 
     <Button
         android:id="@+id/btnSend"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_below="@id/tvMessages"
+        android:layout_below="@id/scrollView"
         android:layout_centerHorizontal="true"
         android:text="SEND" />
+
+    <ScrollView
+        android:id="@+id/scrollView"
+        android:layout_width="match_parent"
+        android:layout_below="@id/tvConnectionInfos"
+        android:layout_height="300dp">
+        <TextView
+            android:id = "@+id/tvMessages"
+            android:layout_width = "match_parent"
+            android:layout_height = "wrap_content"
+            android:hint="Messages"
+            android:inputType = "textMultiLine"
+            android:textAppearance = "@style/Base.TextAppearance.AppCompat.Medium" />
+    </ScrollView>
 </RelativeLayout>