src/com/example/udpresponder/UdpRespondActivity.java

   1 package com.example.udpresponder;
   2
   3 import java.net.InetAddress;
   4 import java.net.InetSocketAddress;
   5 import java.net.DatagramPacket;
   6 import java.net.DatagramSocket;
   7 import android.app.Activity;
   8 import android.os.Bundle;
   9 import android.os.Handler;
  10 import android.os.Message;
  11 import android.os.SystemClock;
  12 import android.widget.TextView;
  13 import android.widget.EditText;
  14 import android.widget.Button;
  15 import android.view.View;
  16 import android.view.View.OnClickListener;
  17
  18 public class UdpRespondActivity extends Activity {
  19
  20         private TextView tv;
  21         private EditText et;
  22
  23         private Handler mHandler = new Handler() {
  24                 public void handleMessage(Message msg) {
  25                         Bundle bdl = msg.getData();
  26                         tv.append(bdl.getString("ln"));
  27                 }
  28         };
  29
  30         private OnClickListener mStartListener = new OnClickListener() {
  31                 public void onClick(View v) {
  32                         CharSequence cs = et.getText();
  33                         tv.append("Start pressed, data: " +
  34                                 cs.toString() +
  35                                 " (unimplemented)\n");
  36                 }
  37         };
  38
  39         private OnClickListener mStopListener = new OnClickListener() {
  40                 public void onClick(View v) {
  41                         tv.append("Stop pressed, exiting\n");
  42                         finish();
  43                 }
  44         };
  45
  46         @Override
  47         public void onCreate(Bundle savedInstanceState) {
  48                 super.onCreate(savedInstanceState);
  49                 setContentView(R.layout.main);
  50                 tv = (TextView)findViewById(R.id.tv);
  51                 tv.append(" Starting\n");
  52                 et = (EditText)findViewById(R.id.text_entry);
  53                 Button btn_start = (Button)findViewById(R.id.btn_start);
  54                 btn_start.setOnClickListener(mStartListener);
  55                 Button btn_stop = (Button)findViewById(R.id.btn_stop);
  56                 btn_stop.setOnClickListener(mStopListener);
  57                 startBgThread();
  58         }
  59
  60         private void println(String str) {
  61                 Bundle bdl = new Bundle();
  62                 bdl.putString("ln", str + "\n");
  63                 Message msg = Message.obtain(mHandler);
  64                 msg.setData(bdl);
  65                 msg.sendToTarget();
  66         }
  67
  68         protected void startBgThread () {
  69                 Thread t = new Thread() {
  70                         public void run() {
  71                                 bgTask();
  72                         }
  73                 };
  74                 t.start();
  75         }
  76
  77         private void bgTask() {
  78                 DatagramSocket s = null;
  79                 try {
  80                         s = new DatagramSocket(9999);
  81                 } catch (java.net.SocketException e) {
  82                         println("socket: " + e);
  83                         return;
  84                 }
  85 //              InetSocketAddress sa = new InetSocketAddress(9999);
  86 //              try {
  87 //                      s.bind(sa);
  88 //              } catch (IllegalArgumentException e) {
  89 //                      println("bind: " + e);
  90 //                      return;
  91 //              } catch (java.net.SocketException e) {
  92 //                      println("bind: " + e);
  93 //                      return;
  94 //              }
  95                 println("Bound to port " + s.getLocalPort());
  96                 while (true) {
  97                         byte[] data = new byte[256];
  98                         DatagramPacket pkt = new DatagramPacket(data, 256);
  99                         try {
 100                                 s.receive(pkt);
 101                         } catch (java.io.IOException e) {
 102                                 println("receive: " + e);
 103                         }
 104                         InetAddress ia = pkt.getAddress();
 105                         int ip = pkt.getPort();
 106                         byte[] id = pkt.getData();
 107                         println(ia.toString() + ":" +
 108                                 ip + " " +
 109                                 id.toString());
 110                 }
 111         }
 112 }