I already resolved the problem by using another class, that handles the websocket client:
import android.app.Activity;
import android.app.Fragment;
import android.os.Build;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
import android.widget.TextView;
import org.java_websocket.client.WebSocketClient;
import org.java_websocket.handshake.ServerHandshake;
import java.net.URI;
import java.net.URISyntaxException;
public class MainActivity extends Activity {
private WebSocketClient mWebSocketClient;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
connectWebSocket();
if (savedInstanceState == null) {
getFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment())
.commit();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
switch (item.getItemId()) {
case R.id.action_settings:
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
}
}
private void connectWebSocket() {
URI uri;
try {
uri = new URI("ws://192.168.1.135:9000/");
} catch (URISyntaxException e) {
e.printStackTrace();
return;
}
mWebSocketClient = new WebSocketClient(uri) {
@Override
public void onOpen(ServerHandshake serverHandshake) {
Log.i("Websocket", "Opened");
mWebSocketClient.send("Hello from " + Build.MANUFACTURER + " " + Build.MODEL);
}
@Override
public void onMessage(String s) {
final String message = s;
runOnUiThread(new Runnable() {
@Override
public void run() {
TextView textView = (TextView)findViewById(R.id.messages);
textView.setText(textView.getText() + "\n" + message);
}
});
}
@Override
public void onClose(int i, String s, boolean b) {
Log.i("Websocket", "Closed " + s);
}
@Override
public void onError(Exception e) {
Log.i("Websocket", "Error " + e.getMessage());
}
};
mWebSocketClient.connect();
}
public void sendMessage(View view) {
EditText editText = (EditText)findViewById(R.id.message);
mWebSocketClient.send(editText.getText().toString());
editText.setText("");
}
}
For anyone that is interested, I've used a Websocket-ChatServer written in PHP:
<?php
$r = $_SERVER['SERVER_ADDR'];
if($r=="::1") $r="localhost";
$host = $r; //'localhost'; //host
$port = '9000'; //port
$null = NULL; //null var
//Create TCP/IP sream socket
$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
//reuseable port
socket_set_option($socket, SOL_SOCKET, SO_REUSEADDR, 1);
//bind socket to specified host
socket_bind($socket, 0, $port);
//listen to port
socket_listen($socket);
//create & add listning socket to the list
$clients = array($socket);
//start endless loop, so that our script doesn't stop
while (true) {
//manage multipal connections
$changed = $clients;
//returns the socket resources in $changed array
socket_select($changed, $null, $null, 0, 10);
//check for new socket
if (in_array($socket, $changed)) {
$socket_new = socket_accept($socket); //accpet new socket
$clients[] = $socket_new; //add socket to client array
$header = socket_read($socket_new, 1024); //read data sent by the socket
perform_handshaking($header, $socket_new, $host, $port); //perform websocket handshake
socket_getpeername($socket_new, $ip); //get ip address of connected socket
$response = mask(json_encode(array('type'=>'system', 'message'=>$ip.' connected'))); //prepare json data
send_message($response); //notify all users about new connection
//make room for new socket
$found_socket = array_search($socket, $changed);
unset($changed[$found_socket]);
}
//loop through all connected sockets
foreach ($changed as $changed_socket) {
//check for any incomming data
while(socket_recv($changed_socket, $buf, 1024, 0) >= 1)
{
$received_text = unmask($buf); //unmask data
$tst_msg = json_decode($received_text); //json decode
$user_name = $tst_msg->name; //sender name
$user_message = $tst_msg->message; //message text
$user_color = $tst_msg->color; //color
//prepare data to be sent to client
$response_text = mask(json_encode(array('type'=>'usermsg', 'name'=>$user_name, 'message'=>$user_message, 'color'=>$user_color)));
send_message($response_text); //send data
break 2; //exist this loop
}
$buf = @socket_read($changed_socket, 1024, PHP_NORMAL_READ);
if ($buf === false) { // check disconnected client
// remove client for $clients array
$found_socket = array_search($changed_socket, $clients);
socket_getpeername($changed_socket, $ip);
unset($clients[$found_socket]);
//notify all users about disconnected connection
$response = mask(json_encode(array('type'=>'system', 'message'=>$ip.' disconnected')));
send_message($response);
}
}
}
// close the listening socket
socket_close($sock);
function send_message($msg)
{
global $clients;
foreach($clients as $changed_socket)
{
@socket_write($changed_socket,$msg,strlen($msg));
}
return true;
}
//Unmask incoming framed message
function unmask($text) {
$length = ord($text[1]) & 127;
if($length == 126) {
$masks = substr($text, 4, 4);
$data = substr($text, 8);
}
elseif($length == 127) {
$masks = substr($text, 10, 4);
$data = substr($text, 14);
}
else {
$masks = substr($text, 2, 4);
$data = substr($text, 6);
}
$text = "";
for ($i = 0; $i < strlen($data); ++$i) {
$text .= $data[$i] ^ $masks[$i%4];
}
return $text;
}
//Encode message for transfer to client.
function mask($text)
{
$b1 = 0x80 | (0x1 & 0x0f);
$length = strlen($text);
if($length <= 125)
$header = pack('CC', $b1, $length);
elseif($length > 125 && $length < 65536)
$header = pack('CCn', $b1, 126, $length);
elseif($length >= 65536)
$header = pack('CCNN', $b1, 127, $length);
return $header.$text;
}
//handshake new client.
function perform_handshaking($receved_header,$client_conn, $host, $port)
{
$headers = array();
$lines = preg_split("/\r\n/", $receved_header);
foreach($lines as $line)
{
$line = chop($line);
if(preg_match('/\A(\S+): (.*)\z/', $line, $matches))
{
$headers[$matches[1]] = $matches[2];
}
}
$secKey = $headers['Sec-WebSocket-Key'];
$secAccept = base64_encode(pack('H*', sha1($secKey . '258EAFA5-E914-47DA-95CA-C5AB0DC85B11')));
//hand shaking header
$upgrade = "HTTP/1.1 101 Web Socket Protocol Handshake\r\n" .
"Upgrade: websocket\r\n" .
"Connection: Upgrade\r\n" .
"WebSocket-Origin: $host\r\n" .
"WebSocket-Location: ws://$host:$port/demo/shout.php\r\n".
"Sec-WebSocket-Accept:$secAccept\r\n\r\n";
socket_write($client_conn,$upgrade,strlen($upgrade));
}
In order to start the websocket server it's needed to run a console command like this: php -q myserver.php
