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安卓第七天笔记--网络编程一

Android对网络的支持

Android完全支持JDK本身的TCP,UDP网络通信API,也可以使用ServerSocket,Socket来建立基于TCP/IP协议的网络通信,还可以使用DatagramSocket,Datagrampacket,MulticastSocket来建立基于UDP的协议网络通信

同时支持JDK提供的URL,URLConnection等网络通信API.

Andoirdgip内置了Apache的HttpClient,这样可以非常方便的发送HTTP请求,并获取HTTP响应.

1.Socket实现

服务器

package com.itheima.server;

import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;

/**
 * ServerSocket 服务端
* @Decription TODO
 * @author 刘楠
 *
 * @time2016-2-22下午4:54:59
 */
public class MyServer {

    public static ArrayList<Socket> socketList = new ArrayList<Socket>();
    public static void main(String[] args) {
    
        
        try {
            //建立serversocket

            ServerSocket serverSocket = new ServerSocket(25000);
            //服务器一直在运行状态
            while(true){
                //开始监听
                Socket socket = serverSocket.accept();
                socketList.add(socket);
                //启动新的线程
                new ServerThread(socket).start();
            }
            
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}


/*
线程类
*/

package com.itheima.server;

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

public class ServerThread extends Thread {
    private Socket socket;
    
    public ServerThread(Socket socket) throws IOException {
        //初始化
        this.socket = socket;        
    }

    @Override
    public void run() {
        String ip = socket.getInetAddress().getHostAddress();
        System.out.println("ip:"+ip);
        BufferedReader br=null;
        OutputStream out = null;
        try {
            br = new BufferedReader(new InputStreamReader(socket.getInputStream(),
                    "UTF-8"));
            out = socket.getOutputStream();
            
            String content = null;
            while((content=br.readLine())!=null){
                System.out.println("来自客户端:"+content);
                //手动加上换行 符,不然没客户端收不到
                out.write((content+"
").toUpperCase().getBytes("utf-8"));
                
                System.out.println("服务发出去了:");
            }        
            out.close();
            br.close();
            socket.close();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
}

布局文件

<?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:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:orientation="vertical"
    tools:context="com.itheima.mutithreadclient.MainActivity">

    <!--接收用户输入的内容-->
    <EditText
        android:id="@+id/input"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:hint="请输入要发送的内容"/>


    <Button
        android:id="@+id/send"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="发送"/>

<!--接收服务返回的内容-->
    <TextView
        android:id="@+id/show"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>
</LinearLayout>

子线程

/**
 * 线程类
 * Created by  刘楠 on 2016-02-22 17:51.
 */
public  class  ClientThread implements  Runnable{
    private static final String TAG = "ClientThread";


    private Socket s;
    // 定义向UI线程发送消息的Handler对象
    private Handler handler;
    // 定义接收UI线程的消息的Handler对象
    public Handler revHandler;
    // 该线程所处理的Socket所对应的输入流
    BufferedReader br = null;
    OutputStream os = null;
    public ClientThread(Handler handler)
    {
        this.handler = handler;
    }
    public void run()
    {
        try
        {
            s = new Socket("192.168.1.103", 25000);
            br = new BufferedReader(new InputStreamReader(
                    s.getInputStream()));
            os = s.getOutputStream();
            // 启动一条子线程来读取服务器响应的数据
            new Thread()
            {
                @Override
                public void run()
                {
                    String content = null;
                    // 不断读取Socket输入流中的内容
                    try
                    {
                        while ((content = br.readLine()) != null)
                        {
                            // 每当读到来自服务器的数据之后，发送消息通知程序
                            // 界面显示该数据
                            Message msg = new Message();
                            msg.what = 0x123;
                            msg.obj = content;
                            handler.sendMessage(msg);
                            Log.i(TAG,"服务返回"+content);
                        }
                    }
                    catch (IOException e)
                    {
                        e.printStackTrace();
                    }
                }
            }.start();
            // 为当前线程初始化Looper
            Looper.prepare();
            // 创建revHandler对象
            revHandler = new Handler()
            {
                @Override
                public void handleMessage(Message msg)
                {
                    // 接收到UI线程中用户输入的数据
                    if (msg.what == 0x345)
                    {
                        // 将用户在文本框内输入的内容写入网络
                        try
                        {
                            //手动加上换行符
                            os.write((msg.obj.toString() + "
")
                                    .getBytes("utf-8"));
                            Log.i(TAG, "输入的" + msg.obj.toString());
                        }
                        catch (Exception e)
                        {
                            e.printStackTrace();
                        }
                    }
                }
            };
            // 启动Looper
            Looper.loop();
        }
        catch (SocketTimeoutException e1)
        {
            System.out.println("网络连接超时！！");
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }

}

Activity

/**
 *
 * 使用ServketSocket做服务通信
 *
 *
 * @author  刘楠
 */
public class MainActivity extends AppCompatActivity {

    private EditText input;

    private TextView show;

    private ClientThread clientThread;

    private Button send;

    private Handler handler;




    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        input = (EditText) findViewById(R.id.input);

        show = (TextView) findViewById(R.id.show);

        send = (Button) findViewById(R.id.send);

        /**
         * 接收到消息要就显示
         */
         handler = new Handler(){
            @Override
            public void handleMessage(Message msg) {

                if(msg.what==0x123){
                    show.append("
"+msg.obj.toString());
                }

            }
        };


        //初始化子线程
        clientThread = new ClientThread(handler);
        //启动子线程
        new Thread(clientThread).start();



        send.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String str = input.getText().toString().trim();

                Message msg=new Message();
                msg.what=0x345;
                msg.obj=str;

                //把内容发给子线程
                clientThread.revHandler.sendMessage(msg);

                //清空文本框
                input.setText("");
            }
        });
    }




}

 

<!--添加网络权限-->
<uses-permission android:name="android.permission.INTERNET"/>

2.URL连接网络

布局

<?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">

    <EditText
        android:id="@+id/et_url"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:hint="请输入URL图片地址"/>

    <Button
        android:onClick="display"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="显示图片地址"/>


    <ImageView
        android:id="@+id/show"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
</LinearLayout>

Activity

/**
 * URL连接网络
 * 获取URL地址
 * 打开流,获取流的内容
 * 
 */
public class MainActivity extends AppCompatActivity {

    /*
    标识表示成功
     */
    private static final int SUCCESS = 1;
    //路径写死了 也可以获取的方式
    private String path ="http://img2.imgtn.bdimg.com/it/u=4114593003,3380074209&fm=21&gp=0.jpg";
    /*
    图片
     */
    Bitmap bitmap;

    /*
    显示图片
     */
    ImageView show;

    /*
    输入的URL
     */
    private EditText et_url;

    private Handler handler;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        et_url = (EditText) findViewById(R.id.et_url);

        show = (ImageView) findViewById(R.id.show);


        handler = new Handler(){

            @Override
            public void handleMessage(Message msg) {

                switch(msg.what){
                    case SUCCESS:
                    show.setImageBitmap(bitmap);
                    break;
                }
            }
        };
    }


    /**
     * 获取输入的地址并显示图片
     * @param v  当前对象
     */
    public void display(View v){


        String strPath = et_url.getText().toString().trim();

        if(TextUtils.isEmpty(strPath)){

            Toast.makeText(this,"输入的路径不能为空",Toast.LENGTH_SHORT).show();
            return ;
        }

        new Thread(new Runnable() {
            @Override
            public void run() {


                try {

                    //获取URL
                    URL url = new URL(path);
                    //打开流获取资源
                    InputStream in = url.openStream();

                    //使用BitmapFactory转换为Bitmap
                    bitmap = BitmapFactory.decodeStream(in);
                    //获取消息
                    Message msg = Message.obtain();
                    msg.what=SUCCESS;
                    msg.obj=bitmap;

                    handler.sendMessage(msg);
                    //关闭
                   // in.close();
                    //把文件保存到本地
                    in =url.openStream();

                    OutputStream out = openFileOutput("test.png",MODE_PRIVATE);

                    byte [] buf = new byte [1024];
                    int len=0;
                    while((len=in.read(buf))!=-1){
                        out.write(buf,0,len);
                    }
                    out.close();
                    in.close();


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

            }
        }).start();

    }
}

添加网络权限

    <!--添加网络权限-->
    <uses-permission android:name="android.permission.INTERNET"/>

3.URLConnection连接网络

使用URLConnection连接网络
*Get方式只要 获取请求地址把请求参数拼接在URL地址后面"?username="+user+"&password="+password
* openConnection
* 设置请求头信息
* connect()建立实际连接
* 获取输入流conn.getInputStream
* 读取输入流中的内容
*
* Post方式,
* 请求地址
* ,将参数单独拼接为一个字符串params="username="+user+"&password="+password
* openConnection
* 设置请求头信息
* connect()建立实际连接
* setDoOuput(true)
* setDoInput(true)
* 写出参数conn.getOutPutStream().write(params.getBytes());
* 获取输入流conn.getInputStream
* 读取输入流中的内容

服务器Servlet

/**
 * LoginServlet
* @Decription 处理登录请求的Servlet
 * @author 刘楠
 *
 * @time2016-2-22下午9:40:48
 */
@WebServlet(urlPatterns={"/login"})
public class LoginServlet extends HttpServlet {

    @SuppressWarnings("deprecation")
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        /*
         * 获取用户名与密码并转换为UTF-8
         */
        String user = request.getParameter("username");
        /*String encode = URLEncoder.encode(user,"iso8859-1");
        String decode = URLDecoder.decode(encode, "UTF-8");*/
        
        String username =new String(user.getBytes("iso8859-1"),"utf-8");
        System.out.println("用户名:"+username);
        
        String pwd=request.getParameter("password");
        
        String password = new String(pwd.getBytes("iso8859-1"), "UTF-8");
        System.out.println("密码:"+password);
        
        /*
         * 这里写死用户名与密码,
         * 正常是去数据库查询
         */
        PrintWriter writer = response.getWriter();
        
        if("admin".equals(username)&& "admin".equals(password)){
            writer.write("SUCCESS");
            
        }else{
            writer.write("FAILURE");
        }
        
        
        
        
            
        
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        System.out.println("================post===============");
        request.setCharacterEncoding("UTF-8");
        String username = request.getParameter("username");
        
        String password = request.getParameter("password");
        System.out.println("username:"+username+",password: "+password);
        
        if("admin".equals(username) && "admin".equals(password)){
            response.getWriter().print("SUCCESS");
        }else{
            response.getWriter().print("failure");
        }
    }

}

View Code

3.1get请求与Post请求

布局

<?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:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:orientation="vertical"
    tools:context="com.itheima.urlconnection.MainActivity">

    <EditText
        android:id="@+id/et_user"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="请输入用户名"/>
    <EditText
        android:id="@+id/et_pwd"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:inputType="textPassword"
        android:hint="请输入密码"/>


    <Button
        android:onClick="get"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="GET请求"/>
    <Button
        android:onClick="post"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="POST  请求"/>


    <TextView
        android:id="@+id/show"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>
</LinearLayout>

Activity

/**
 * 使用URLConnection连接网络
 *Get方式只要 获取请求地址把请求参数拼接在URL地址后面"?username="+user+"&password="+password
 * openConnection
 * 设置请求头信息
 * connect()建立实际连接
 * 获取输入流conn.getInputStream
 * 读取输入流中的内容
 *
 * Post方式,
 * 请求地址
 * ,将参数单独拼接为一个字符串params="username="+user+"&password="+password
 * openConnection
 * 设置请求头信息
 * connect()建立实际连接
 * setDoOuput(true)
 * setDoInput(true)
 * 写出参数conn.getOutPutStream().write(params.getBytes());
 * 获取输入流conn.getInputStream
 * 读取输入流中的内容
 *
 *
 */
public class MainActivity extends AppCompatActivity {

    private static final int SUCCESS = 1;
    private static final int ERROR =2 ;
    private static final String TAG ="MainActivity" ;
    /*
        请求的路径
         */
    private String path="http://192.168.1.103:8080/Login/login";

    private TextView show;

    private EditText et_user;

    private EditText et_pwd;


    /*
    Handler 消息处理
     */

    private Handler handler;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        /*
        初始化
         */
        et_user = (EditText) findViewById(R.id.et_user);
        et_pwd = (EditText) findViewById(R.id.et_pwd);

        show = (TextView) findViewById(R.id.show);

        handler = new Handler(){
            @Override
            public void handleMessage(Message msg) {
                switch (msg.what){
                    case SUCCESS:
                        show.setText(msg.obj.toString());
                        break;
                    case ERROR:
                        Toast.makeText(MainActivity.this,"网络异常",Toast.LENGTH_SHORT).show();
                        break;
                }
            }
        };
    }


    /**
     * get 方式请求
     * @param v 当前组件
     */
    public void get(View v){

        String username = et_user.getText().toString().trim();

        String password = et_pwd.getText().toString().trim();

        if(TextUtils.isEmpty(username) || TextUtils.isEmpty(password)){

            Toast.makeText(this,"用户名或者密码不能为空",Toast.LENGTH_SHORT).show();
            return ;
        }

        final String urlName =path+"?username="+username+"&password="+password;
        /*
        get请求
         */
        new Thread(){
            @Override
            public void run() {


                try {
                    //获取请求URL地址
                    URL url=new URL(urlName);
                    //打开连接
                    URLConnection conn = url.openConnection();

                    //设置超时时间
                    conn.setConnectTimeout(5000);



                    // 设置通用的请求属性
                    conn.setRequestProperty("accept", "*/*");
                    conn.setRequestProperty("connection", "Keep-Alive");
                    conn.setRequestProperty("user-agent",
                            "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)");


                    //建立实际连接
                    conn.connect();
                    //获取所有的行响应 头字段

                    Map<String,List<String>> map = conn.getHeaderFields();


                    Set<String> keySet = map.keySet();
                    for (String key:keySet ) {
                        Log.i(TAG,"key"+key+"------------>"+map.get(key));
                    }

                    //定义输入流来获取URL的响应

                    InputStream in = conn.getInputStream();
                    ByteArrayOutputStream bas= new ByteArrayOutputStream();
                            
                     int len=0;
                    
                    byte [] buf = new byte[1024];
                    
                    while((len=in.read(buf))!=-1){
                        bas.write(buf,0,len);
                    }

                    //转换为字符串
                    String result=bas.toString();

                    //设置消息对象
                    Message msg = Message.obtain();
                    //成功就发送SUCCESS
                    msg.what=SUCCESS;
                    msg.obj=result;
                    //发送
                    handler.sendMessage(msg);

                } catch (Exception e) {
                    e.printStackTrace();
                    //出异常就发送ERROR
                    Message msg = Message.obtain();

                    msg.what=ERROR;
                    handler.sendMessage(msg);
                }


            }
        }.start();

    }

    /**
     * post 方式请求
     * @param v 当前组件
     */
    public void post(View v){
        String username = et_user.getText().toString().trim();

        String password = et_pwd.getText().toString().trim();

        if(TextUtils.isEmpty(username) || TextUtils.isEmpty(password)){

            Toast.makeText(this,"用户名或者密码不能为空",Toast.LENGTH_SHORT).show();
            return ;
        }


        final String params="username="+username+"&password="+password;
        /*
        post请求
         */
        new Thread(){
            @Override
            public void run() {
                try {
                    //获取请求URL地址
                    URL url=new URL(path);
                    //打开连接
                    URLConnection conn = url.openConnection();

                    //设置超时时间
                    conn.setConnectTimeout(5000);



                    // 设置通用的请求属性
                    conn.setRequestProperty("accept", "*/*");
                    conn.setRequestProperty("connection", "Keep-Alive");
                    conn.setRequestProperty("user-agent",
                            "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)");

                    /*
                    post请求必须有以下2行
                     */
                    conn.setDoOutput(true);
                    conn.setDoInput(true);

                    OutputStream out = conn.getOutputStream();

                    out.write(params.getBytes());



                    //建立实际连接

                    //获取所有的行响应 头字段

                    Map<String,List<String>> map = conn.getHeaderFields();


                    Set<String> keySet = map.keySet();
                    for (String key:keySet ) {
                        Log.i(TAG,"key"+key+"------------>"+map.get(key));
                    }

                    //定义输入流来获取URL的响应

                    InputStream in = conn.getInputStream();
                    ByteArrayOutputStream bas= new ByteArrayOutputStream();

                    int len=0;

                    byte [] buf = new byte[1024];

                    while((len=in.read(buf))!=-1){
                        bas.write(buf,0,len);
                    }

                    //转换为字符串
                    String result=bas.toString();

                    //设置消息对象
                    Message msg = Message.obtain();
                    //成功就发送SUCCESS
                    msg.what=SUCCESS;
                    msg.obj=result;
                    //发送
                    handler.sendMessage(msg);

                } catch (Exception e) {
                    e.printStackTrace();
                    //出异常就发送ERROR
                    Message msg = Message.obtain();

                    msg.what=ERROR;
                    handler.sendMessage(msg);
                }


            }
        }.start();

    }
}

View Code

添加网络权限

    <!--添加网络权限-->
    <uses-permission android:name="android.permission.INTERNET"/>

4.Http网络连接

和URLConnection非常类似只获取连接为HttpURULConnection

/**
 * 使用HttpURLConnection连接网络
 *Get方式只要 获取请求地址把请求参数拼接在URL地址后面"?username="+user+"&password="+password
 * openConnection
 * 设置请求方法setRequestMethod("GET")必须大写
 *
 * 获取输入流conn.getInputStream
 * 读取输入流中的内容
 *
 * Post方式,
 * 请求地址
 * ,将参数单独拼接为一个字符串params="username="+user+"&password="+password
 * openConnection
 * 设置请求方法setRequestMethod("POST")必须大写
 * setDoOuput(true)
 * setDoInput(true)
 * 写出参数conn.getOutPutStream().write(params.getBytes());
 * 获取输入流conn.getInputStream
 * 读取输入流中的内容
 *
 *
 */

/**
 * 使用HttpURLConnection连接网络
 *Get方式只要 获取请求地址把请求参数拼接在URL地址后面"?username="+user+"&password="+password
 * openConnection
 * 设置请求方法setRequestMethod("GET")必须大写
 *
 * 获取输入流conn.getInputStream
 * 读取输入流中的内容
 *
 * Post方式,
 * 请求地址
 * ,将参数单独拼接为一个字符串params="username="+user+"&password="+password
 * openConnection
 * 设置请求方法setRequestMethod("POST")必须大写
 * setDoOuput(true)
 * setDoInput(true)
 * 写出参数conn.getOutPutStream().write(params.getBytes());
 * 获取输入流conn.getInputStream
 * 读取输入流中的内容
 *
 *
 */
public class MainActivity extends  AppCompatActivity{
private static final int SUCCESS = 1;
private static final int ERROR =2 ;
private static final String TAG ="MainActivity" ;
    /*
        请求的路径
         */
private String path="http://192.168.1.100:8080/Login/login";

private TextView show;

private EditText et_user;

private EditText et_pwd;


    /*
    Handler 消息处理
     */

private Handler handler;
@Override
protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        /*
        初始化
         */
        et_user = (EditText) findViewById(R.id.et_user);
        et_pwd = (EditText) findViewById(R.id.et_pwd);

        show = (TextView) findViewById(R.id.show);

        handler = new Handler(){
@Override
public void handleMessage(Message msg) {
        switch (msg.what){
        case SUCCESS:
        show.setText(msg.obj.toString());
        break;
        case ERROR:
        Toast.makeText(MainActivity.this, "网络异常", Toast.LENGTH_SHORT).show();
        break;
        }
        }
        };
        }


/**
 * get 方式请求
 * @param v 当前组件
 */
public void get(View v){

        String username = et_user.getText().toString().trim();

        String password = et_pwd.getText().toString().trim();

        if(TextUtils.isEmpty(username) || TextUtils.isEmpty(password)){

        Toast.makeText(this,"用户名或者密码不能为空",Toast.LENGTH_SHORT).show();
        return ;
        }

final String urlName =path+"?username="+username+"&password="+password;
        /*
        get请求
         */
        new Thread(){
@Override
public void run() {


        try {
        //获取请求URL地址
        URL url=new URL(urlName);
        //打开连接
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();

        //设置超时时间
        conn.setConnectTimeout(5000);
        //设置请求方式
        conn.setRequestMethod("GET");
        //获取响应码
        int code = conn.getResponseCode();

        if(code==200) {
                //获取所有的行响应 头字段

                Map<String, List<String>> map = conn.getHeaderFields();


                Set<String> keySet = map.keySet();
                for (String key : keySet) {
                        Log.i(TAG, "key" + key + "------------>" + map.get(key));
                }

                //定义输入流来获取URL的响应

                InputStream in = conn.getInputStream();
                ByteArrayOutputStream bas = new ByteArrayOutputStream();

                int len = 0;

                byte[] buf = new byte[1024];

                while ((len = in.read(buf)) != -1) {
                        bas.write(buf, 0, len);
                }

                //转换为字符串
                String result = bas.toString();

                //设置消息对象
                Message msg = Message.obtain();
                //成功就发送SUCCESS
                msg.what = SUCCESS;
                msg.obj = result;
                //发送
                handler.sendMessage(msg);
        }else{
                //出异常就发送ERROR
                Message msg = Message.obtain();

                msg.what=ERROR;
                handler.sendMessage(msg);
        }



        } catch (Exception e) {
        e.printStackTrace();
        //出异常就发送ERROR
        Message msg = Message.obtain();

        msg.what=ERROR;
        handler.sendMessage(msg);
        }


        }
        }.start();

        }

/**
 * post 方式请求
 * @param v 当前组件
 */
public void post(View v){
        String username = et_user.getText().toString().trim();

        String password = et_pwd.getText().toString().trim();

        if(TextUtils.isEmpty(username) || TextUtils.isEmpty(password)){

        Toast.makeText(this,"用户名或者密码不能为空",Toast.LENGTH_SHORT).show();
        return ;
        }


final String params="username="+username+"&password="+password;
        /*
        post请求
         */
        new Thread(){
@Override
public void run() {
        try {
        //获取请求URL地址
        URL url=new URL(path);
        //打开连接
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();

        //设置超时时间
        conn.setConnectTimeout(5000);
         //设置请求方式
         conn.setRequestMethod("POST");
          /*
          post请求必须有以下2行
         */
        conn.setDoOutput(true);


        OutputStream out = conn.getOutputStream();

        out.write(params.getBytes());



        //建立实际连接

        //获取所有的行响应 头字段

        Map<String,List<String>> map = conn.getHeaderFields();


        Set<String> keySet = map.keySet();
        for (String key:keySet ) {
        Log.i(TAG,"key"+key+"------------>"+map.get(key));
        }

        //定义输入流来获取URL的响应

        InputStream in = conn.getInputStream();
        ByteArrayOutputStream bas= new ByteArrayOutputStream();

        int len=0;

        byte [] buf = new byte[1024];

        while((len=in.read(buf))!=-1){
        bas.write(buf,0,len);
        }

        //转换为字符串
        String result=bas.toString();

        //设置消息对象
        Message msg = Message.obtain();
        //成功就发送SUCCESS
        msg.what=SUCCESS;
        msg.obj=result;
        //发送
        handler.sendMessage(msg);

        } catch (Exception e) {
        e.printStackTrace();
        //出异常就发送ERROR
        Message msg = Message.obtain();

        msg.what=ERROR;
        handler.sendMessage(msg);
        }


        }
        }.start();

        }
        }

View Code

5.使用ApacheHttpClient

/**
 * 使用HttpClient做网络请求 5.0过期,6.0不可用
 * 
 * 建立HttpClient对象 get请求 建立httpGet对象
 * setParams来设置参数
 * 也可以将参数拼接在URL地址后面
 * 
 * post请求 建立HttpPost对象
 * 设置请求体
 * setEntity
 * new UrlEncodedFormEntity(List<? extends NameValuePair>)
 * 设置参数
 * 
 * 获取行响应码,判断,
 * 获取行响应体
 * 
 * 
 * 
 * @author 刘楠
 * 
 *         2016-2-23上午12:04:06
 */
public class MainActivity extends Activity {

    private static final int SUCCESS = 1;
    private static final int ERROR = 2;
    private static final String TAG = "MainActivity";
    /*
     * 请求的路径
     */
    private String path = "http://192.168.1.100:8080/Login/login";

    private TextView show;

    private EditText et_user;

    private EditText et_pwd;

    private HttpClient client;

    /*
     * Handler 消息处理
     */

    private Handler handler;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        /*
         * 初始化
         */
        client = new DefaultHttpClient();

        et_user = (EditText) findViewById(R.id.et_user);
        et_pwd = (EditText) findViewById(R.id.et_pwd);

        show = (TextView) findViewById(R.id.show);

        handler = new Handler() {
            @Override
            public void handleMessage(Message msg) {
                switch (msg.what) {
                case SUCCESS:
                    show.setText(msg.obj.toString());
                    break;
                case ERROR:
                    Toast.makeText(MainActivity.this, "网络异常",
                            Toast.LENGTH_SHORT).show();
                    break;
                }
            }
        };
    }

    /**
     * get 方式请求
     * 
     * @param v
     *            当前组件
     */
    
    private String urlName ;
    public void get(View v) {

        String username = et_user.getText().toString().trim();

        String password = et_pwd.getText().toString().trim();

        if (TextUtils.isEmpty(username) || TextUtils.isEmpty(password)) {

            Toast.makeText(this, "用户名或者密码不能为空", Toast.LENGTH_SHORT).show();
            return;
        }
        
        try {
             urlName =  path + "?username="
                    + URLEncoder.encode(username, "UTF-8") + "&password="
                    + URLEncoder.encode(password, "UTF-8");
        } catch (UnsupportedEncodingException e1) {
            
            e1.printStackTrace();
        }

        /*
         * get请求
         */
        new Thread() {
            @Override
            public void run() {
                try {
                    HttpGet get = new HttpGet(urlName);
                    /**
                     * 可以使用HttpParams设置参数 HttpParams params = new
                     * BasicHttpParams();
                     */
                    // 开始执行
                    HttpResponse response = client.execute(get);
                    // 获取响应码
                    int code = response.getStatusLine().getStatusCode();

                    if (code == 200) {
                        // 获取内容响应体中的内容
                        InputStream in = response.getEntity().getContent();

                        ByteArrayOutputStream bas = new ByteArrayOutputStream();

                        int len = 0;
                        byte[] buf = new byte[1024];

                        while ((len = in.read(buf)) != -1) {
                            bas.write(buf, 0, len);
                        }
                        String result = bas.toString();
                        in.close();
                        //设置消息
                        Message msg = Message.obtain();

                        msg.what = SUCCESS;
                        msg.obj = result;
                        handler.sendMessage(msg);

                    } else {
                        Message msg = Message.obtain();

                        msg.what = SUCCESS;

                        handler.sendMessage(msg);

                    }

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

        }.start();
        

    }

    /**
     * post 方式请求
     * 
     * @param v
     *            当前组件
     * @throws UnsupportedEncodingException
     */
    public void post(View v) {
        final String username = et_user.getText().toString().trim();

        final String password = et_pwd.getText().toString().trim();

        if (TextUtils.isEmpty(username) || TextUtils.isEmpty(password)) {

            Toast.makeText(this, "用户名或者密码不能为空", Toast.LENGTH_SHORT).show();
            return;
        }
        /*
         * post请求
         */
        new Thread() {
            @Override
            public void run() {
                try {
                    //建立Post请求
                    HttpPost post = new HttpPost(path);
                    
                    List<NameValuePair> parameters = new ArrayList<NameValuePair>();
                    
                    
                    parameters.add(new BasicNameValuePair("username", username));
                    parameters.add(new BasicNameValuePair("password", password));
                    //设置请求体与字符编码
                    post.setEntity(new UrlEncodedFormEntity(parameters,"UTF-8") );
                    
                    //执行
                    HttpResponse response = client.execute(post);
                    //获取响应码
                    int code = response.getStatusLine().getStatusCode();
                    
                    if (code == 200) {
                        // 获取内容响应体中的内容
                        InputStream in = response.getEntity().getContent();

                        ByteArrayOutputStream bas = new ByteArrayOutputStream();

                        int len = 0;
                        byte[] buf = new byte[1024];

                        while ((len = in.read(buf)) != -1) {
                            bas.write(buf, 0, len);
                        }
                        String result = bas.toString();
                        in.close();
                        //设置消息
                        Message msg = Message.obtain();

                        msg.what = SUCCESS;
                        msg.obj = result;
                        handler.sendMessage(msg);

                    } else {
                        Message msg = Message.obtain();

                        msg.what = SUCCESS;

                        handler.sendMessage(msg);

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

        }.start();

    }

}

View Code

6.WebView

goBack():后退

goForward():前进

loadUrl(String url):加载指定URL的网页

boolean zoomln():放大网页

zoomOut():缩小网页

布局

<?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">

    <EditText
        android:id="@+id/et_url"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="请输入url网址"/>


    <WebView
        android:id="@+id/wv_show"
        android:layout_width="match_parent"
        android:layout_height="match_parent">


    </WebView>
</LinearLayout>

布局

Activity

/**
 * WebView小型浏览器
 *
 */
public class MainActivity extends AppCompatActivity {

    /*
    接收输入的URL
     */
    private EditText et_url;

    /*
    显示网页内容
     */
    private WebView wv_show;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        et_url = (EditText) findViewById(R.id.et_url);

        wv_show = (WebView) findViewById(R.id.wv_show);

    }


    @Override
    public boolean onKeyDown(int keyCode,KeyEvent event) {

        if(keyCode==KeyEvent.KEYCODE_MENU){

            String urlStr = et_url.getText().toString().trim();
            //加载
            wv_show.loadUrl(urlStr);

            return  true;
        }

        return false;
    }

}

添加权限

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

7.使用WebHTML加载HTML代码

WebView提供了一具

loadData(String data,String mimeType ,String encoding)方法用于加载HTML,这个方法加载中文时会有乱码

还有一个

loadDataWithURL(String data,String mimeType ,String encoding,String historyUrl)方法是第一个方法的加强,

data:指定的HTML代码

mimeType:指定HTML代码的MIME类型,对象HTML代码可指定为text/html

encoding:指定HTML代码编码所有的字符集:UTF-8

布局中只有一个WebView

/**

 * WebView显示HTML

 */

public class MainActivity extends AppCompatActivity {



    private WebView webView_show;



    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);



        //获取webView组件

        webView_show = (WebView) findViewById(R.id.webView_show);



        StringBuilder sb = new StringBuilder();



        sb.append("<html>");



        sb.append("<head>");

        sb.append("<title> 欢迎WebView显示HTML</title>");

        sb.append("</head>");



        sb.append("<body>");

        sb.append("<h1 align='center' style='color:red'>显示中文标题</h1>");



        sb.append("</body>");



        sb.append("</html>");



        //加载并显示HTML这个中文会显示乱码

        //webView_show.loadData(sb.toString(),"text/html","utf-8");



        webView_show.loadDataWithBaseURL(null,sb.toString(),"text/html","utf-8",null);



    }

}

9.WebView使用JavaScript调用Android

步骤:

1.调用WebView的get getSettings方法获取WebSettings

2.启用JAVAScript调用功能

webSettings.setJavaScriptEnable(true)

3.调用webView的addJavaScript(Object obj,String name)方法

4.在javaScript脚本中通过刚才暴露的name对象调用Android

5.对象的方法上必须加上注解

/**
- * 这具注解只能用在方法
  - */
    - @JavascriptInterface

Html在assets目录下

<!DOCTYPE html>

<html>

<head>

    <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>

    <title>JS 调用</title>

</head>



<body>

<!-- 注意此处的myObj是Android暴露出来的对象 -->

<input type="button" value="弹Toast"

       onclick="person.show();"/>

<input type="button" value="图书列表"

       onclick="person.showList();"/>

</body>

</html>

布局

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout

    xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent">



    <WebView

        android:id="@+id/webView"

        android:layout_width="match_parent"

        android:layout_height="match_parent"/>

</RelativeLayout>

JAVABean:

/**

 * Created by  刘楠 on 2016-02-23 09:00.

 */



public class Person {





    private String name;



    private int age;



    private Context mContext;



    public Person(Context context){



        this.mContext = context;

    }







    public Person(String name, int age) {

        this.name = name;

        this.age = age;

    }



    public String getName() {

        return name;

    }



    public void setName(String name) {

        this.name = name;

    }



    public int getAge() {

        return age;

    }



    public void setAge(int age) {

        this.age = age;

    }



    @JavascriptInterface

    public void show(){

        Toast.makeText(mContext,"姓名"+this.name+",年龄:"+age,Toast.LENGTH_SHORT).show();

    }





    /**

     * 这具注解只能用在方法

     */

    @JavascriptInterface

    public void showList(){



        new AlertDialog.Builder(mContext)

       //设置标题

        .setTitle("人员列表")

       .setIcon(R.mipmap.ic_launcher)

       .setItems(new String [] {"JAVA","Android","C++","C","PYTHON"},null)

                .setPositiveButton("确定",null)

                .setNegativeButton("取消",null)

                .create().show();









    }

}

Activity

/**

 * WebView使用JavaScript

 * 

 */

public class MainActivity extends AppCompatActivity {



    private WebView webView;







    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);



        webView = (WebView) findViewById(R.id.webView);

        webView.loadUrl("file:///android_asset/test.html");



        //获取WebView设置对象

        WebSettings webSettings = webView.getSettings();



        //启用javaScript

        webSettings.setJavaScriptEnabled(true);



        Person person = new Person(this);



        person.setName("张三");

        person.setAge(18);



        //传递对象

        webView.addJavascriptInterface(person, "person");

    }

}

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原文地址：https://www.cnblogs.com/liunanjava/p/5207890.html