<&#63;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.oak.d3_xml.MainActivity">     <TextView     android:id="@+id/tv"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:text="Hello World!" />   <Button     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:text="生成"     android:id="@+id/BT_create"/>   <Button     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:text="读取"     android:id="@+id/bt_read"/> </LinearLayout>

 package com.oak.d3_xml;   import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.widget.Button; import android.widget.TextView; import android.widget.Toast;   import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.nodelist; import org.xml.sax.SAXException;   import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.OutputStream;   import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserconfigurationException; import javax.xml.transform.Transformer; import javax.xml.transform.TransformerConfigurationException; import javax.xml.transform.TransformerException; import javax.xml.transform.TransformerFactory; import javax.xml.transform.dom.DOMSource; import javax.xml.transform.stream.StreamResult;     public class MainActivity extends AppCompatActivity {   PRivate TextView textView;//用于展示读取xml的内容   private Button bt_create;//用于创建xml文件   private Button bt_read;//用于读取xml文件   private File file;//xml文件路径   @override   protected void onCreate(Bundle savedInstancestate) {     suPEr.onCreate(savedInstanceState);     setContentView(R.layout.activity_main);     file = new File(getFilesDir(),"languages.xml");//获取到xml文件     textView = (TextView) findViewById(R.id.tv);//拿到textView控件     bt_create = (Button) findViewById(R.id.bt_create);//拿到创建按钮     bt_read = (Button) findViewById(R.id.bt_read);//拿到读取按钮       bt_create.setOnClickListener(new View.OnClickListener() {       @Override       public void onClick(View view) {         //这里利用的是dom对xml进行操作的         //实例化一个DocmentBuilderFactory，调用其静态方法获取         DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();         try {           //实例化一个DocumentBuilder           DocumentBuilder builder = builderFactory.newDocumentBuilder();           //实例化一个xml文件           Document newxml = builder.newDocument();           //创建一个根标签           Element languages = newxml.createElement("languages");           //为其设置属性           languages.setattribute("cat","it");           //for循坏3次，分别创建出三个标签，每个标签都包含内容           for (int i=0;i<3;i++){             //创建languages的子标签lan             Element lan = newxml.createElement("lan");             //设置属性             lan.setAttribute("id",i+"");             //创建lan的子标签             Element name = newxml.createElement("name");             //设置内容             name.setTextContent("Java"+i);             //创建lan的子标签             Element ide = newxml.createElement("ide");             //设置内容             ide.setTextContent("Eclipse"+i);             //将name和ide分别加入lan这个标签中             lan.appendChild(name);             lan.appendChild(ide);             //将lan将入languages标签中             languages.appendChild(lan);           }           //将languages加入到xml文件中           newxml.appendChild(languages);           //实例化Transformer工厂           TransformerFactory transformerFactory = TransformerFactory.newInstance();           //获取到Transformer           Transformer transformer = transformerFactory.newTransformer();           //设置输出格式           transformer.setOutputProperty("encoding","UTF-8");           //设置输出流           OutputStream os = new FileOutputStream(file);           //将文件写出           transformer.transform(new DOMSource(newxml),new StreamResult(os));           Toast.makeText(getApplicationContext(),"生成成功",Toast.LENGTH_SHORT).show();         } catch (ParserConfigurationException e) {           e.printStackTrace();         } catch (TransformerConfigurationException e) {           e.printStackTrace();         } catch (FileNotFoundException e) {           e.printStackTrace();         } catch (TransformerException e) {           e.printStackTrace();         }       }     });     bt_read.setOnClickListener(new View.OnClickListener() {       @Override       public void onClick(View view) {         //获取到DocumentBuilder的工厂实例化         DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();         try {           //拿到DocumentBuilder           DocumentBuilder builder = builderFactory.newDocumentBuilder();           //解析xml文件           Document xml = builder.parse(file);           //获取其根标签           Element languages = xml.getDocumentElement();           //根据子标签进行查找，返回的是一个list集合           NodeList list = languages.getelementsbytagname("lan");           textView.setText("");//将textView中的内容置空           for (int i=0; i<list.getLength(); i++){             //获取到子标签lan             Element lan = (Element) list.item(i);             //获取到他的属性             String id = lan.getAttribute("id");             //获取到他的子标签name的内容             String name = lan.getElementsByTagName("name").item(0).getTextContent();             //获取到他的子标签ide的内容             String ide = lan.getElementsByTagName("ide").item(0).getTextContent();             //显示到textView中             textView.append(id+"/n"+name+"/n"+ide+"/n");           }         } catch (ParserConfigurationException e) {           e.printStackTrace();         } catch (SAXException e) {           e.printStackTrace();         } catch (IOException e) {           e.printStackTrace();         }         }     });   } }