XML文件解析

谈一下Android小白的xml文件解析

本文代码参考黑马程序员android授课内容

从网上下载了一个名为weather.xml(黑马程序员授课的一个文件)文件，如下：

<?xml version="1.0" encoding="utf-8"?>
<weather>
        <channel id ='1'>
             <city>北京</city>
             <temp>25°</temp>
             <wind>3</wind>
             <pm250>300</pm250>
             
        </channel>
        
         <channel id ='2'>
             <city>郑州</city>
             <temp>20°</temp>
             <wind>4</wind>
             <pm250>300</pm250>
             
        </channel>
        
        <channel id ='3'>
             <city>长春</city>
             <temp>10°</temp>
             <wind>4</wind>
             <pm250>100</pm250>
             
        </channel>
        
        <channel id ='4'>
             <city>沈阳</city>
             <temp>20°</temp>
             <wind>1</wind>
             <pm250>50</pm250>
        </channel>


</weather>

下面就来读取此文件的内容：

将文件放在资产目录下：在main目录中新建名为assets的目录，将文件放在里面：

首先根据文件新建了一个JavaBean文件：MyJavaBean.java:

package com.lgqchinese.xmlread;

public class MyJavaBean {
    private String id;
    private String city;
    private String temp;
    private String wind;
    private String pm250;

    public void setId(String id) {
        this.id = id;
    }

    public void setCity(String city) {
        this.city = city;
    }

    public void setTemp(String temp) {
        this.temp = temp;
    }

    public void setWind(String wind) {
        this.wind = wind;
    }

    public void setPm250(String pm250) {
        this.pm250 = pm250;
    }

    public String getId() {
        return id;
    }

    public String getCity() {
        return city;
    }

    public String getTemp() {
        return temp;
    }

    public String getWind() {
        return wind;
    }

    public String getPm250() {
        return pm250;
    }

    @Override
    public String toString() {
        return "MyJavaBean{" +
                "id='" + id + '\'' +
                ", city='" + city + '\'' +
                ", temp='" + temp + '\'' +
                ", wind='" + wind + '\'' +
                ", pm250='" + pm250 + '\'' +
                '}';
    }
}

然后新建解析文件类来对文件进行解析：

package com.lgqchinese.xmlread;

import android.util.Xml;

import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;

import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

public class XmlReadFunc {
    public static List<MyJavaBean> parserXML(InputStream inputStream) throws XmlPullParserException, IOException {
        List<MyJavaBean> weatherLists = null;
        MyJavaBean myJavaBean = null;
        //获取实例
        XmlPullParser pullParser = Xml.newPullParser();
        //设置XmlPullParser参数
        pullParser.setInput(inputStream, "utf-8");
        //获取文档的时间类型
        int type = pullParser.getEventType();
        while (type != XmlPullParser.END_DOCUMENT) {
            //判断解析到哪个节点
            switch (type) {
                case XmlPullParser.START_TAG://解析开始标签
                    //判断具体开始标签
                    if ("weather".equals(pullParser.getName())) {
                        weatherLists = new ArrayList<MyJavaBean>();
                    } else if ("channel".equals(pullParser.getName())) {
                        //创建myJavaBean对象
                        myJavaBean = new MyJavaBean();
                        //获取id值
                        String id = pullParser.getAttributeValue(0);
                        myJavaBean.setId(id);

                    } else if ("city".equals(pullParser.getName())) {
                        //获取city内容
                        String city = pullParser.nextText();
                        myJavaBean.setCity(city);

                    } else if ("temp".equals(pullParser.getName())) {
                        //获取temp内容
                        String temp = pullParser.nextText();
                        myJavaBean.setTemp(temp);

                    } else if ("wind".equals(pullParser.getName())) {
                        //获取wind内容
                        String wind = pullParser.nextText();
                        myJavaBean.setWind(wind);

                    } else if ("pm250".equals(pullParser.getName())) {
                        //获取pm250内容
                        String pm250 = pullParser.nextText();
                        myJavaBean.setPm250(pm250);

                    }
                    break;
                case XmlPullParser.END_TAG://解析结束标签
                    //判断具体的结束标签
                    if ("channel".equals(pullParser.getName())) {
                        //把javabean对象放入集合中
                        weatherLists.add(myJavaBean);
                    }
                    break;
            }


            //不停的向下解析
            type = pullParser.next();
        }


        return weatherLists;
    }
}

MainActivity.java:

package com.lgqchinese.xmlread;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Toast;

import org.w3c.dom.Text;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

public class MainActivity extends AppCompatActivity {

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

        try {
            //显示xml数据
            TextView textView = findViewById(R.id.tv);
            //通过上下文获取资产管理者
            InputStream inputStream = getAssets().open("weather.xml");
            //调用解析方法
            List<MyJavaBean> weatherLists = null;
            try {
                weatherLists = XmlReadFunc.parserXML(inputStream);
            } catch (XmlPullParserException e) {
                e.printStackTrace();
            }

            StringBuffer sb = new StringBuffer();
            for (MyJavaBean myJavaBean:weatherLists){
                sb.append(myJavaBean.toString());
            }

            //把数据展示到控件上
            textView.setText(sb.toString());
        } catch (IOException e) {
            e.printStackTrace();
            Toast.makeText(MainActivity.this,"sidfg",Toast.LENGTH_SHORT).show();
        }
    }
}