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

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

    package="com.example.yanlei.wifi" >

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

    <!-- 在SDCard中创建与删除文件权限 -->

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

    <!-- 连接<a href="http://www.it165.net/news/nhlw/" target="_blank" class="keylink">互联网</a>Internet权限 -->

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

    <!-- GPS定位权限 -->

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

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

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

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

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

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

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

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

    <application

        android:allowBackup="true"

        android:icon="@mipmap/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme" >

        <activity

            android:name=".MainActivity"

            android:label="@string/app_name" >

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

    </application>

</manifest>

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

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

    android:orientation="vertical"

    android:layout_width="fill_parent"

    android:layout_height="fill_parent"

    >

    <Button

        android:id="@+id/btn1"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        android:text="创建XML文件"

        />

    <Button

        android:id="@+id/btn2"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        android:text="DOM解析XML"

        />

    <TextView

        android:id="@+id/result"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        />

</LinearLayout>

package com.example.yanlei.wifi;

import android.content.Context;

import android.net.wifi.ScanResult;

import android.net.wifi.WifiManager;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.view.LayoutInflater;

import android.view.Menu;

import android.view.MenuItem;

import android.view.View;

import android.view.ViewGroup;

import android.widget.BaseAdapter;

import android.widget.ImageView;

import android.widget.ListView;

import android.widget.TextView;

import android.widget.Toast;

import java.io.File;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;

import org.w3c.dom.Element;

import org.w3c.dom.NodeList;

import org.xml.sax.SAXException;

import org.xmlpull.v1.XmlPullParser;

import org.xmlpull.v1.XmlPullParserException;

import org.xmlpull.v1.XmlPullParserFactory;

import org.xmlpull.v1.XmlSerializer;

import android.app.Activity;

import android.os.Bundle;

import android.util.Log;

import android.util.Xml;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.TextView;

import android.widget.Toast;

import java.util.List;

public class MainActivity extends AppCompatActivity {

    private static final String BOOKS_PATH = "/sdcard/books.xml";

    private View mButton1,mButton2,mButton3;

    private TextView mTextView;

    @Override

    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        setupViews();

    }

    //初始化工作

    private void setupViews(){

        mTextView = (TextView)findViewById(R.id.result);

        mButton1 = (View)findViewById(R.id.btn1);

        mButton2 = (View)findViewById(R.id.btn2);

        mButton1.setOnClickListener(new Button1ClickListener());

        mButton2.setOnClickListener(new Button2ClickListener());

    }

    private class Button1ClickListener implements View.OnClickListener {

        public void onClick(View v) {

            createXmlFile();

        }

    }

    private class Button2ClickListener implements View.OnClickListener {

        public void onClick(View v) {

            domParseXML();

        }

    }

    //创建xml文件

    private void createXmlFile(){

        File linceseFile = new File(BOOKS_PATH);

        try{

            linceseFile.createNewFile();

        }catch (IOException e) {

            Log.e("IOException", "exception in createNewFile() method");

        }

        FileOutputStream fileos = null;

        try{

            fileos = new FileOutputStream(linceseFile);

        }catch (FileNotFoundException  e) {

            Log.e("FileNotFoundException", "can't create FileOutputStream");

        }

        XmlSerializer serializer = Xml.newSerializer();

        try {

            serializer.setOutput(fileos,"UTF-8");

            serializer.startDocument(null, true);

            serializer.startTag(null, "books");

            for(int i = 0; i < 3; i ++){

                serializer.startTag(null, "book");

                serializer.startTag(null, "bookname");

                serializer.text("Android教程" + i);

                serializer.endTag(null, "bookname");

                serializer.startTag(null, "bookauthor");

                serializer.text("Frankie" + i);

                serializer.endTag(null, "bookauthor");

                serializer.endTag(null, "book");

            }

            serializer.endTag(null, "books");

            serializer.endDocument();

            serializer.flush();

            fileos.close();

        } catch (Exception e) {

            Log.e("Exception","error occurred while creating xml file");

        }

        Toast.makeText(getApplicationContext(), "创建xml文件成功!", Toast.LENGTH_SHORT).show();

    }

    //dom解析xml文件

    private void domParseXML(){

        File file = new File(BOOKS_PATH);

        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

        DocumentBuilder db = null;

        try {

            db = dbf.newDocumentBuilder();

        } catch (ParserConfigurationException e) {

            e.printStackTrace();

        }

        Document doc = null;

        try {

            doc = db.parse(file);

        } catch (SAXException e) {

            e.printStackTrace();

        } catch (IOException e) {

            e.printStackTrace();

        }

        Element root = doc.getDocumentElement();

        NodeList books = root.getElementsByTagName("book");

        String res = "本结果是通过dom解析:" + "/n";

        for(int i = 0; i < books.getLength();i++){

            Element book = (Element)books.item(i);

            Element bookname = (Element)book.getElementsByTagName("bookname").item(0);

            Element bookauthor = (Element)book.getElementsByTagName("bookauthor").item(0);

            res += "书名: " + bookname.getFirstChild().getNodeValue() + " " +

                    "作者: " + bookauthor.getFirstChild().getNodeValue() + "/n";

        }

        mTextView.setText(res);

    }

    @Override

    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.

        getMenuInflater().inflate(R.menu.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.

        int id = item.getItemId();

        //noinspection SimplifiableIfStatement

        if (id == R.id.action_settings) {

            return true;

        }

        return super.onOptionsItemSelected(item);

    }

}