有些时候,我们需要生成一个XML文件,生成XML文件的方法有很多,
如:
可以只使用一个StringBuilder组拼XML内容,然后把内容写入到文件中;
或者使用DOM API生成XML文件,或者也可以使用pull解析器生成XML文件,这里推荐大家使用Pull解析器。
Strings.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">lession03_xml</string>
<string name="action_settings">Settings</string>
<string name="hello_world">Hello world!</string>
<string name="btn_sax">采用sax解析xml文件</string>
<string name="btn_dom">采用dom解析方式解析</string>
<string name="btn_pull">采用pull解析方式解析</string>
<string name="btn_cpull">采用pull解析生成xml文件</string>
</resources>
activity_xml.xml
<RelativeLayout 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"
tools:context=".XmlActivity" >
<Button
android:id="@+id/button_cpull"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/btn_pull"
android:layout_alignRight="@+id/btn_pull"
android:layout_below="@+id/btn_pull"
android:layout_marginTop="20dp"
android:text="@string/btn_cpull" />
<Button
android:id="@+id/btn_sax"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:text="@string/btn_sax" />
<Button
android:id="@+id/btn_pull"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/btn_dom"
android:layout_alignRight="@+id/btn_dom"
android:layout_below="@+id/btn_dom"
android:layout_marginTop="68dp"
android:text="@string/btn_pull" />
<Button
android:id="@+id/btn_dom"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/btn_sax"
android:layout_alignRight="@+id/btn_sax"
android:layout_below="@+id/btn_sax"
android:layout_marginTop="60dp"
android:text="@string/btn_dom" />
</RelativeLayout>
Person.java
package com.example.lession03_xml.domain;
import java.io.Serializable;
/**
* 创建一个javabean存储xml解析的数据
*
* @author chenhj
*
*/
public class Person implements Serializable {
/**
*
*/
private static final long serialVersionUID = 1L;
private int id;
private String name;
private short age;
public Person() {
super();
// TODO Auto-generated constructor stub
}
public Person(int id, String name, short age) {
super();
this.id = id;
this.name = name;
this.age = age;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public short getAge() {
return age;
}
public void setAge(short age) {
this.age = age;
}
}
XMLPullService.java
package com.example.lession03_xml.service;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlSerializer;
import android.R.bool;
import android.os.Environment;
import android.provider.ContactsContract.CommonDataKinds.Event;
import android.util.Xml;
import com.example.lession03_xml.domain.Person;
/**
* 采用pull解析xml文件 事件驱动 开始,结束元素事件 产生的事件是一个数字,通过switch语句体现
*
* @author zhaoyazhi
*
*/
public class XMLPullService {
public List<Person> getPerson(InputStream inputStream) throws Exception {
List<Person> persons = null;
Person person = null;
// android提供一个类XmlPullParser,得到pull解析器
XmlPullParser pullParser = Xml.newPullParser();
// 设置要进行解析的内容,不是立刻发生,调用才发生
pullParser.setInput(inputStream, "utf-8");
/* <?xml version="1.0" encoding="UTF-8"?> */
// 触发第一个事件 用数字形式表示 开始文档事件
int event = pullParser.getEventType();
// 不等于文档的结束时间
while (event != XmlPullParser.END_DOCUMENT) {
// 属于开始文档事件
switch (event) {
case XmlPullParser.START_DOCUMENT:
persons = new ArrayList<Person>();
break;
case XmlPullParser.START_TAG:
/* <persons> */
if ("person".equals(pullParser.getName())) {
/* <person id="23"> */
int id = new Integer(pullParser.getAttributeValue(0));
person = new Person();
person.setId(id);
}
if (person != null) {
/* <name> */
if ("name".equals(pullParser.getName())) {
// 返回文本的值
/* 李明 */
person.setName(pullParser.nextText());
}
/* <age> */
if ("age".equals(pullParser.getName())) {
/* 30 */person.setAge(new Short(pullParser.nextText()));
}
}
break;
// 结束元素事件
/* </persons> */
case XmlPullParser.END_TAG:
// 当前解析器指向的节点为person
if ("person".equals(pullParser.getName())) {
persons.add(person);
person = null;
}
break;
}
// 解析器向后解析
event = pullParser.next();
}
return persons;
}
// 写入
public boolean save(List<Person> persons) {
// 采用pull解析器进行实现
if (Environment.getExternalStorageState().equals(
Environment.MEDIA_MOUNTED)) {
// 获取SD卡目录 文件对象
File sdCardDir = Environment.getExternalStorageDirectory();
// 创建文件
File file = new File(sdCardDir, "mycsdn.xml");
// xml持久化器
XmlSerializer serializer = Xml.newSerializer();
FileOutputStream fos = null;
try {
// 根据文件对象创建一个文件的输出流对象
fos = new FileOutputStream(file);
// 设置输出流及编码
serializer.setOutput(fos, "UTF-8");
// 设置文件的开始
serializer.startDocument("utf-8", true);
// persons标签开始
serializer.startTag(null, "persons");
for (Person person : persons) {
// person标签开始
serializer.startTag(null, "person");
// person 属性
serializer.attribute(null, "id", person.getId() + "");
// 设置person标签的子标签name
serializer.startTag(null, "name");
serializer.text(person.getName() + "");
serializer.endTag(null, "name");
// 设置person标签子标签age
serializer.startTag(null, "age");
serializer.text(person.getAge() + "");
serializer.endTag(null, "age");
// person标签结束
serializer.endTag(null, "person");
}
// persons标签的结束
serializer.endTag(null, "persons");
// 文件的结束
serializer.endDocument();
fos.flush();
fos.close();
return true;
} catch (Exception e) {
e.printStackTrace();
}
}
return false;
}
}
XmlActivity.java
package com.example.lession03_xml;
import java.io.InputStream;
import java.util.List;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import com.example.lession03_xml.domain.Person;
import com.example.lession03_xml.service.XMLContentHandlerService;
import com.example.lession03_xml.service.XMLDomService;
import com.example.lession03_xml.service.XMLPullService;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
public class XmlActivity extends Activity {
// 声明控件
public Button btn_sax, btn_dom, btn_pull, btn_cpull;
public XMLDomService xmlDomService;
public XMLPullService xmlPullService;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// 设置显示的视图
setContentView(R.layout.activity_xml);
// 实例化
xmlDomService = new XMLDomService();
xmlPullService = new XMLPullService();
// 通过findViewById方法获取控件对象
btn_sax = (Button) findViewById(R.id.btn_sax);
btn_dom = (Button) findViewById(R.id.btn_dom);
btn_pull = (Button) findViewById(R.id.btn_pull);
btn_cpull = (Button) findViewById(R.id.button_cpull);
// 给按钮注册事件
btn_sax.setOnClickListener(new MyClickListener());
btn_dom.setOnClickListener(new MyClickListener());
btn_pull.setOnClickListener(new MyClickListener());
btn_cpull.setOnClickListener(new MyClickListener());
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.xml, menu);
return true;
}
class MyClickListener implements View.OnClickListener {
@Override
public void onClick(View v) {
// 获取组件的id
int id = v.getId();
switch (id) {
case R.id.btn_sax:
Toast.makeText(XmlActivity.this, "采用sax解析xml文件案例",
Toast.LENGTH_LONG).show();
// sax解析的工厂对象
SAXParserFactory factory = SAXParserFactory.newInstance();
try {
// 得到sax的解析器
SAXParser saxParser = factory.newSAXParser();
// 创建handler对象
XMLContentHandlerService handlerService = new XMLContentHandlerService();
// 获取到了 asserts目录中 csdn.xml文件
InputStream is = getAssets().open("csdn.xml");
// 直接解析 InputStream的流对象
saxParser.parse(is, handlerService);
// 通过 handlerService对象
Toast.makeText(XmlActivity.this,
"---" + handlerService.getPersons().size(),
Toast.LENGTH_LONG).show();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
break;
case R.id.btn_dom:
InputStream is = null;
try {
// 获取读取文件的输入流对象
is = getAssets().open("csdn.xml");
// 采用
List<Person> persons = xmlDomService.parseXML(is);
//
Toast.makeText(XmlActivity.this,
"" + persons.get(0).getName(), Toast.LENGTH_LONG)
.show();
} catch (Exception e) {
e.printStackTrace();
}
break;
case R.id.btn_pull:
List<Person> persons = null;
try {
persons = xmlPullService.getPerson(getAssets().open(
"csdn.xml"));
} catch (Exception e) {
e.printStackTrace();
}
if (persons != null) {
Toast.makeText(
XmlActivity.this,
"采用pull解析xml文件" + persons.get(0).getName() + "--"
+ persons.get(1).getName(),
Toast.LENGTH_LONG).show();
}
break;
case R.id.button_cpull:
// 重新生成一个xml文件 mycsdn.xml
List<Person> persons1 = null;
try {
persons1 = xmlPullService.getPerson(getAssets().open(
"csdn.xml"));
// 重新生成一个新xml文件
boolean flag = xmlPullService.save(persons1);
if (flag) {
Toast.makeText(XmlActivity.this, "采用pull解析生产xml文件成功",
Toast.LENGTH_LONG).show();
} else {
Toast.makeText(XmlActivity.this, "采用pull解析生产xml文件失败",
Toast.LENGTH_LONG).show();
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
break;
default:
break;
}
}
}
}