android学习日记——基于UDP的聊天demo

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.ytdb.demo.MainActivity">

<EditText
android:id="@+id/edit_ip"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:hint="IP地址" />

<EditText
android:id="@+id/edit_port"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:hint="端口号"
android:text="1026" />

<TextView
android:id="@+id/text_chat"
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="7"
android:textSize="20sp" />

<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:orientation="horizontal">

<EditText
android:id="@+id/edit_content"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="5"
android:hint="请输入文字" />

<Button
android:id="@+id/bt_send"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="2"
android:text="发送" />
</LinearLayout>
</LinearLayout>

package com.ytdb.demo;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Messag
b353
e;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

public class MainActivity extends Activity implements View.OnClickListener {
private TextView text_chat;
private EditText edit_ip;
private EditText edit_port;
private EditText edit_content;
private Button bt_send;
private StringBuffer sb = new StringBuffer();  //缓存收到的数据
private String address;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
edit_ip = (EditText) findViewById(R.id.edit_ip);
edit_port = (EditText) findViewById(R.id.edit_port);
edit_content = (EditText) findViewById(R.id.edit_content);
text_chat = (TextView) findViewById(R.id.text_chat);
bt_send = (Button) findViewById(R.id.bt_send);
reciveData();
bt_send.setOnClickListener(this);
new Thread(new Runnable() {
@Override
public void run() {//开启一个线程判断是否有用户输入
while (true) {
String con = edit_content.getText().toString().trim();
Message msg = Message.obtain();
if (!TextUtils.isEmpty(con)) {
msg.what = 0x111;
handler_input.sendMessage(msg);
} else {
msg.what = 0x222;
handler_input.sendMessage(msg);
}

}
}
}).start();
}

public void reciveData() {
new Thread(new Runnable() {
@Override
public void run() {
try {
byte buff[] = new byte[8192];  //存放接收到的数据最大容量8MB
DatagramSocket socket = new DatagramSocket(1026); //监听port接收客户端数据（自己指定）
DatagramPacket packet = new DatagramPacket(buff, buff.length);
while (true) {
socket.receive(packet); //接收客户端的数据报
String con = new String(packet.getData());
if (!TextUtils.isEmpty(con)) {
address = packet.getAddress().toString();
Message msg = Message.obtain();
msg.obj = con;
handler.sendMessage(msg);     //发送从远程客户端接收的数据到消息队列
}
}

} catch (Exception e) {
e.printStackTrace();
}

}
}).start();
}

@Override
public void onClick(View v) {
final String ip = edit_ip.getText().toString().trim();     //获取用户的输入的ip地址
final String port = edit_port.getText().toString().trim();  //获取用户的输入的端口号
final String content = edit_content.getText().toString().trim();//获取用户的发送内容
if (!TextUtils.isEmpty(ip) && !TextUtils.isEmpty(port)) {
new Thread(new Runnable() {
@Override
public void run() {
try {
Integer p = Integer.parseInt(port);
InetAddress inetAddress = InetAddress.getByName(ip);
DatagramPacket packet = new DatagramPacket(content.getBytes(), content.getBytes().length, inetAddress, p);
DatagramSocket socket = new DatagramSocket();
socket.send(packet);  //发送数据报
sb.append("本机-->" + content + "\n");  //本机发送的消息
} catch (Exception e) {
e.printStackTrace();
}
}
}).start();

} else
Toast.makeText(this, "ip地址或port不能为空", Toast.LENGTH_LONG).show();
edit_content.setText(""); //清空发送消息的编辑框
}

private Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
String con = (String) msg.obj;
sb.append(address+ "-->" + con + "\n");
text_chat.setText(sb);
}
};
private Handler handler_input = new Handler() {
@Override
public void handleMessage(Message msg) {         //根据接收的消息判断是否获取按钮焦点
if (msg.what == 0x111) {
bt_send.setEnabled(true);
} else if (msg.what == 0x222) {
bt_send.setEnabled(false);
}
}
};

}

<uses-permission android:name="android.permission.INTERNET"></uses-permission>