安卓小程序——聊天室（一）

    为什么这里要有聊天室（一）呢？其实这个是我的Java项目。之前写了个Java聊天室，虽然不是很完美但是，运行起来问题也不大。能较完美的运行我的聊天室Java代码也贴上吧。好做复习使用。

    共分为四个类。

       1、服务器类

package chatting;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;

public class MultiTalkServer {
    static int i = 0;
    static int clientNum = 0;
    //容器：储存每一个用户的socket
    private List<ServerThread> servers = new ArrayList<ServerThread>();
    public static void main(String[] args) throws IOException{
        new MultiTalkServer().startChatting();
    }
    //主函数
    public void startChatting() throws IOException{
        ServerSocket serverSocket = null;
        boolean listening = true;
        try {
            serverSocket = new ServerSocket(4477);
        }catch(Exception e){
            System.out.println("couldn't listen on port");
            System.exit(-1);
        }
        while ( listening ){
            Socket socket = serverSocket.accept();
            System.out.println("有客户端已连接！");
            ServerThread serverThread = new ServerThread(socket,clientNum);

            //将创建的线程放入容器
            servers.add(serverThread);

            new Thread(serverThread).start();
            clientNum++;
        }
        serverSocket.close();
    }

    //多线程创建多个用户可共享的服务器，为方便访问内部变量，故设为内部类线程
    private class ServerThread implements Runnable {
        Socket socket = null;
        private String  line;
        private int clientNum;
        private BufferedReader is;
        private PrintWriter os;
        public ServerThread(Socket socket,int num){
            this.socket = socket;
            this.clientNum = num + 1;

        }

        public void run(){
            try{
                is = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                os = new PrintWriter(socket.getOutputStream());

                line = clientNum + ":" + is.readLine();
                while (!line.equals(clientNum + ":" + "bye")){

                    //遍历容器，当遍历到自身时不发送，否则发送

                    for(ServerThread others:servers){
                        if (others == this){
                            continue;
                        }
                        others.send(line);
                    }
                    System.out.println(line);
                    line = clientNum + ":" + is.readLine();
                }
                os.close();
                is.close();
                socket.close();
            }catch (Exception e){
                System.out.println("Error: " + e);
            }
        }

        //服务器发送数据
        private void send(String msg){
            os.println(msg);
            os.flush();
        }


    }

}

        2、客户类

package chatting;

import java.net.Socket;

public class TalkClient {
    static boolean tag = true;
    public static void main(String[] args) {
        try{
            //向本机的4477端口发出客户请求
            Socket socket = new Socket("127.0.0.1",4477);

            new Thread(new sendThread(socket)).start();
            new Thread(new ReceiveThread(socket)).start();
            if (!tag) socket.close();
        } catch (Exception e){
            System.out.println("Error:" + e);
        }
    }
}

        3、客户端接收消息线程

package chatting;

import java.io.*;
import java.net.Socket;

public class ReceiveThread implements Runnable {
    private BufferedReader is;
    private String msg;

    public ReceiveThread(Socket socket){
        try {
            is = new BufferedReader(new InputStreamReader(socket.getInputStream()));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    @Override
    public void run() {
        try {
         
            while (!msg.equals("bye")){
                System.out.println("client " + msg);
                msg = is.readLine();
            }
        } catch (IOException e) {
//            e.printStackTrace();
        }
    }
}

        4、客户端发消息线程

package chatting;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;

public class sendThread implements Runnable {

    private BufferedReader is ;
    private PrintWriter os;
    String msg;
    public sendThread(Socket socket){
        try {
            is = new BufferedReader(new InputStreamReader(System.in));
            os = new PrintWriter(socket.getOutputStream());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    @Override
    public void run() {

        try {
            msg = is.readLine();
            while (!msg.equals("bye")) {
                os.println(msg);
                os.flush();
                System.out.println("Server:" + msg);
                msg = is.readLine();
            }
            TalkClient.tag = false;
        } catch (IOException e) {
//            e.printStackTrace();
        }
    }
}

    这个程序可以实现最简单的聊天。运行顺序就是先运行服务器端，在运行客户端，打开一个客户端就是创建了一个客户端，了两个就是创建了两个。

由于正在学习安卓，所以准备把他移植到 安卓上。起初想的是，就是把客户端输出换成了EditText显示，客户端接收换成了RecyclerView显示，应该很简单，但是，事实证明我想多了。

首先创建一个RecyclerView，方法很正常。首先是layout.xml文件

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

    <android.support.v7.widget.RecyclerView
        android:id="@+id/msg_recycler_view"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"/>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <EditText
            android:id="@+id/input_text"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:hint="Please Input"
            android:maxLines="2" />

        <Button
            android:id="@+id/send"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Send"
            android:textAllCaps="false" />
    </LinearLayout>

</LinearLayout>

其次是msgitem.xml文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="10dp">

    <LinearLayout
        android:id="@+id/left_layout"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="@drawable/message_left"
        android:layout_gravity="left">

        <TextView
            android:id="@+id/left_msg"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:layout_margin="10dp" />

    </LinearLayout>

    <LinearLayout

        android:id="@+id/right_layout"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="@drawable/message_right"
        android:layout_gravity="right"
        >

        <TextView
            android:layout_gravity="center"
            android:layout_margin="10dp"
            android:id="@+id/right_msg"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />
    </LinearLayout>

</LinearLayout>

接着是Msg.java和MsgAdapter.java

package com.example.administrator.chattingroom;

public class Msg {
    public static final int TYPE_RECEIVED = 0;
    public static final int TYPE_SEND = 1;
    private String content;
    private int type;

    public Msg(String content,int type){
        this.content = content;
        this.type = type;
    }

    public String getContent() {
        return content;
    }

    public int getType() {
        return type;
    }
}

package com.example.administrator.chattingroom;

import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.LinearLayout;
import android.widget.TextView;

import java.util.List;

public class MsgAdapter extends RecyclerView.Adapter<MsgAdapter.ViewHolder> {

    private List<Msg> mMsgList;

    static class ViewHolder extends RecyclerView.ViewHolder{
        LinearLayout leftLayout;
        LinearLayout rightLayout;
        TextView leftMsg;
        TextView rightMsg;
        public ViewHolder(View view){
            super(view);
            leftLayout = view.findViewById(R.id.left_layout);
            rightLayout = view.findViewById(R.id.right_layout);
            leftMsg = view.findViewById(R.id.left_msg);
            rightMsg = view.findViewById(R.id.right_msg);
        }

    }

    public MsgAdapter(List<Msg> msgList){
        mMsgList = msgList;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.msg_item,parent,false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(MsgAdapter.ViewHolder holder, int position) {
        Msg msg = mMsgList.get(position);
        if (msg.getType() == Msg.TYPE_RECEIVED){
            holder.leftLayout.setVisibility(View.VISIBLE);
            holder.rightLayout.setVisibility(View.GONE);
            holder.leftMsg.setText(msg.getContent());
        }
        else if (msg.getType() == Msg.TYPE_SEND){
            holder.rightLayout.setVisibility(View.VISIBLE);
            holder.leftLayout.setVisibility(View.GONE);
            holder.rightMsg.setText(msg.getContent());
        }
    }


    @Override
    public int getItemCount() {
        return mMsgList.size();
    }
}

这样子准备工作 就做完了。接下来就是功能代码的实现了。第一是服务器代码，照搬，根本没有影响。就下来就是MainActivity.java的写法了。

开始我不管怎么改都无法连上服务器，就很伤，百度，百度，却怎么也找不到错误原因，最后在一个不知名的地方找到了我的原因，原来如果我想像Java那样直接链接到本机ip就不能用127.0.0.1了，因为安卓的ip默认的本机ip是10.0.2.2，所以在服务器端的socket声明就应该是

client = new Socket("10.0.2.2", 4477);

但是接着又出现问题了，由于安卓规定网络申请不能在主线程中。所以没办法只能在主线程中再开一个线程了。最后当我感觉到万事俱备，只欠东风之时，又出问题了，从服务器接收到的信息不能同步到手机显示上面。。。。后来查了一下，需要使用一个Handler函数进行刷屏，终于跌跌撞撞的完成了。哎，不容易。

package com.example.administrator.chattingroom;

import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

import org.w3c.dom.Text;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    private String receive;

    static boolean tag = true;

    private String message;

    private List<Msg> msgList = new ArrayList<>();

    private EditText inputText,show;

    private Button send;

    private RecyclerView msgRecyclerView;

    private MsgAdapter adapter;

    private Socket client;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.layout);
//        initMsgs();
        inputText = findViewById(R.id.input_text);
        send = findViewById(R.id.send);

        msgRecyclerView = findViewById(R.id.msg_recycler_view);
        LinearLayoutManager  layoutManager = new LinearLayoutManager(this);
        msgRecyclerView.setLayoutManager(layoutManager);
        adapter = new MsgAdapter(msgList);
        msgRecyclerView.setAdapter(adapter);
        send.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                final String content = inputText.getText().toString();
                new Thread(){
                    @Override
                    public void run() {
                        try {
                            PrintWriter os = new PrintWriter(client.getOutputStream());
                            os.println(content);
                            os.flush();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                }.start();
                message = content;
                System.out.println(message);
                if (!"".equals(content)){
                    Msg msg = new Msg(content,Msg.TYPE_SEND);
                    msgList.add(msg);
                    adapter.notifyItemInserted(msgList.size()-1);
                    msgRecyclerView.scrollToPosition(msgList.size()-1);
                    inputText.setText("");
                }
            }
        });

//        new Thread(new ReceiveThread(client)).start();
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    client = new Socket("10.0.2.2", 4477);
                    BufferedReader is = new BufferedReader(new InputStreamReader(client.getInputStream()));
                    receive = is.readLine();
                    System.out.println(receive);
                    Message message = new Message();
                    message.what = 1;
                    String[] aa = receive.split(":",2);
                    message.obj = aa[1];
                    handler.sendMessage(message);

                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }).start();

    }
    Handler handler = new Handler(){
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            if (msg.what == 1){
                Msg msg1 = new Msg(msg.obj.toString(),Msg.TYPE_RECEIVED);
                msgList.add(msg1);
                adapter.notifyItemInserted(msgList.size()-1);
                msgRecyclerView.scrollToPosition(msgList.size()-1);
            }
        }
    };
//    private void initMsgs(){
//        Msg msg1 = new Msg("Hello guy.",Msg.TYPE_RECEIVED);
//        msgList.add(msg1);
//        Msg msg2 = new Msg("Hello,who is that?",Msg.TYPE_SEND);
//        msgList.add(msg2);
//    }

}

最后记住申请网络访问权限。

按程序大致就这样当时还是有BUG。

就是只能你一句我一句的发，不知道怎么该，还有好多问题emmmm啊啊啊，安卓真难，不容易不容易。。。

这两天不再学安卓了。要期末考试了，只能专心应付考试了