我有两个 android 平板电脑，我想通过套接字编程将消息从客户端发送到服务器。我粘贴了示例代码来制作服务器和客户端应用程序并将它们安装在两个安卓平板电脑上。都连接到 wifi
在客户端应用程序上有一个编辑文本，我应该在其中输入一个 IP 地址，然后在下面的按钮称为“连接电话”。
在单击“连接电话按钮”之前，我应该在编辑文本中输入什么 IP 地址
这是“连接电话”按钮的 onclick 监听器
private OnClickListener connectListener = new OnClickListener() {
@Override
public void onClick(View v) {
if (!connected) {
serverIpAddress = serverIp.getText().toString();
if (!serverIpAddress.equals("")) {
Thread cThread = new Thread(new ClientThread());
cThread.start();
}
}
}
};
客户端和服务器应用程序的完整代码如下所示；
客户端代码:
package com.example.client;
// import statements
public class ClientActivity extends Activity {
private EditText serverIp;
private Button connectPhones;
private String serverIpAddress = "";
private boolean connected = false;
private Handler handler = new Handler();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.client);
serverIp = (EditText) findViewById(R.id.server_ip);
connectPhones = (Button) findViewById(R.id.connect_phones);
connectPhones.setOnClickListener(connectListener);
}
private OnClickListener connectListener = new OnClickListener() {
@Override
public void onClick(View v) {
if (!connected) {
serverIpAddress = serverIp.getText().toString();
if (!serverIpAddress.equals("")) {
Thread cThread = new Thread(new ClientThread());
cThread.start();
}
}
}
};
public class ClientThread implements Runnable {
public void run() {
try {
InetAddress serverAddr = InetAddress.getByName(serverIpAddress);
Log.d("ClientActivity", "C: Connecting...");
Socket socket = new Socket(serverAddr, 8080);
connected = true;
while (connected) {
try {
Log.d("ClientActivity", "C: Sending command.");
PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket
.getOutputStream())), true);
// where you issue the commands
out.println("Hey Server!");
Log.d("ClientActivity", "C: Sent.");
} catch (Exception e) {
Log.e("ClientActivity", "S: Error", e);
}
}
socket.close();
Log.d("ClientActivity", "C: Closed.");
} catch (Exception e) {
Log.e("ClientActivity", "C: Error", e);
connected = false;
}
}
}
}
服务器代码；
package com.example.server;
// import statements
public class ServerActivity extends Activity {
private TextView serverStatus;
// default ip
// public static String SERVERIP ="10.0.2.15";
// designate a port
public static final int SERVERPORT = 8080;
private Handler handler = new Handler();
private ServerSocket serverSocket;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.server);
serverStatus = (TextView) findViewById(R.id.server_status);
SERVERIP = getLocalIpAddress();
Thread fst = new Thread(new ServerThread());
fst.start();
}
public class ServerThread implements Runnable {
public void run() {
try {
if (SERVERIP != null) {
handler.post(new Runnable() {
@Override
public void run() {
serverStatus.setText("Listening on IP: " + SERVERIP);
}
});
serverSocket = new ServerSocket(SERVERPORT);
while (true) {
// listen for incoming clients
Socket client = serverSocket.accept();
handler.post(new Runnable() {
@Override
public void run() {
serverStatus.setText("Connected.");
}
});
try {
BufferedReader in = new BufferedReader(new InputStreamReader(client.getInputStream()));
String line = null;
while ((line = in.readLine()) != null) {
Log.d("ServerActivity", line);
handler.post(new Runnable() {
@Override
public void run() {
// do whatever you want to the front end
// this is where you can be creative
}
});
}
break;
} catch (Exception e) {
handler.post(new Runnable() {
@Override
public void run() {
serverStatus.setText("Oops. Connection interrupted. Please reconnect your phones.");
}
});
e.printStackTrace();
}
}
} else {
handler.post(new Runnable() {
@Override
public void run() {
serverStatus.setText("Couldn't detect internet connection.");
}
});
}
} catch (Exception e) {
handler.post(new Runnable() {
@Override
public void run() {
serverStatus.setText("Error");
}
});
e.printStackTrace();
}
}
}
// gets the ip address of your phone's network
private String getLocalIpAddress() {
try {
for (Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements();) {
NetworkInterface intf = en.nextElement();
for (Enumeration<InetAddress> enumIpAddr = intf.getInetAddresses(); enumIpAddr.hasMoreElements();) {
InetAddress inetAddress = enumIpAddr.nextElement();
if (!inetAddress.isLoopbackAddress()) { return inetAddress.getHostAddress().toString(); }
}
}
} catch (SocketException ex) {
Log.e("ServerActivity", ex.toString());
}
return null;
}
@Override
protected void onStop() {
super.onStop();
try {
// make sure you close the socket upon exiting
serverSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
日志错误；
01-22 18:37:40.100: E/ClientActivity(19568): C: Error
01-22 18:37:40.100: E/ClientActivity(19568): java.net.ConnectException: failed to connect to /10.0.2.15 (port 8080): connect failed: EHOSTUNREACH (No route to host)
01-22 18:37:40.100: E/ClientActivity(19568): at libcore.io.IoBridge.connect(IoBridge.java:114)
01-22 18:37:40.100: E/ClientActivity(19568): at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192)
01-22 18:37:40.100: E/ClientActivity(19568): at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)
01-22 18:37:40.100: E/ClientActivity(19568): at java.net.Socket.startupSocket(Socket.java:566)
01-22 18:37:40.100: E/ClientActivity(19568): at java.net.Socket.<init>(Socket.java:225)
01-22 18:37:40.100: E/ClientActivity(19568): at com.example.client.ClientActivity$ClientThread.run(ClientActivity.java:60)
01-22 18:37:40.100: E/ClientActivity(19568): at java.lang.Thread.run(Thread.java:856)
01-22 18:37:40.100: E/ClientActivity(19568): Caused by: libcore.io.ErrnoException: connect failed: EHOSTUNREACH (No route to host)
01-22 18:37:40.100: E/ClientActivity(19568): at libcore.io.Posix.connect(Native Method)
01-22 18:37:40.100: E/ClientActivity(19568): at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:85)
01-22 18:37:40.100: E/ClientActivity(19568): at libcore.io.IoBridge.connectErrno(IoBridge.java:127)
01-22 18:37:40.100: E/ClientActivity(19568): at libcore.io.IoBridge.connect(IoBridge.java:112)
最佳答案
当您将 Android 设备连接到 WiFi 网络时，它会被分配一个 IP 地址。该 IP 地址在“设置 > 关于手机 > 状态 > IP 地址”下可见。现在，在您的情况下，服务器应用程序在一台平板电脑上运行，客户端在另一台平板电脑上运行。我们只需要服务器的 IP 地址，您可以使用此方法找到它。在客户端应用对应区域输入这个IP，就设置好了 .
关于android - 让这个客户端服务器 android 应用程序工作。我在 edittext 窗口中输入什么 IP 地址？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/14472473/