Android之Jsoup解析数据

                                                           Android之Jsoup解析数据

jsoup 简介

Java 程序在解析 HTML 文档时，相信大家都接触过 htmlparser 这个开源项目，我曾经在 IBM DW 上发表过两篇关于 htmlparser 的文章，分别是：从 HTML 中攫取你所需的信息和 扩展 HTMLParser 对自定义标签的处理能力。但现在我已经不再使用 htmlparser 了，原因是 htmlparser 很少更新，但最重要的是有了 jsoup 。

jsoup 是一款 Java 的 HTML 解析器，可直接解析某个 URL 地址、HTML 文本内容。它提供了一套非常省力的 API，可通过 DOM，CSS 以及类似于 jQuery 的操作方法来取出和操作数据。

jsoup 的主要功能如下：

1. 从一个 URL，文件或字符串中解析 HTML；

2. 使用 DOM 或 CSS 选择器来查找、取出数据；

3. 可操作 HTML 元素、属性、文本；

jsoup 是基于 MIT 协议发布的，可放心使用于商业项目。

jsoup 的主要类层次结构如图 1 所示：

图 1. jsoup 的类层次结构

          下面我们来看看Jsoup解析的一个案例：

1.主函数：MaActivity.class

import java.io.IOException;import java.net.MalformedURLException;import java.net.URL;import java.util.ArrayList;import org.jsoup.Jsoup;import org.jsoup.nodes.Document;import org.jsoup.select.Elements;import android.os.Bundle;import android.os.Handler;import android.app.Activity;import android.content.Intent;import android.util.Log;import android.view.Menu;import android.view.View;import android.widget.AdapterView;import android.widget.AdapterView.OnItemClickListener;import android.widget.ListView;public class MainActivity extends Activity {protected static final String TAG = "MainActivity";private ListView listView;private ArrayList<Info> list;Handler handler=new Handler(){public void handleMessage(android.os.Message msg) {if(msg.what==0){listView.setAdapter(new ListViewAdapter(MainActivity.this, list));}};};@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);//初始化数据listView = (ListView) findViewById(R.id.listview);//创建集合list = new ArrayList<Info>();//解析数据parseHtml();//对ListView设置点击事件listView.setOnItemClickListener(new OnItemClickListener() {@Overridepublic void onItemClick(AdapterView<?> arg0, View arg1, int arg2,long arg3) {Intent intent=new Intent(MainActivity.this,WebActivity.class);intent.putExtra("path", list.get(arg2).getHref());startActivity(intent);}});}private void parseHtml() {new Thread(){public void run() {try {Document parse = Jsoup.parse(new URL("http://www.cnbeta.com/topics/444.htm"),5000);Elements Eleclass = parse.getElementsByClass("title");Elements Elenewsinfo = parse.getElementsByClass("newsinfo");Elements Elepic = parse.getElementsByClass("pic");int size = Eleclass.size();for (int i = 0; i < size; i++) {String title = Eleclass.get(i).getElementsByTag("a").text();String href = Eleclass.get(i).getElementsByTag("a").attr("href");String newsinfo = Elenewsinfo.get(i).getElementsByTag("p").text();String pic = Elepic.get(i).getElementsByTag("img ").attr("src");list.add(new Info(title, newsinfo, pic, href));}for (Info info : list) {Log.i(TAG, info.toString());}handler.sendEmptyMessage(0);} catch (IOException e) {e.printStackTrace();}};}.start();}}

2.主函数的布局：activity_main.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"     >    <ListView        android:id="@+id/listview"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="@string/hello_world" /></RelativeLayout>

3.适配器的布局：listview_item.xml

<?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="horizontal" >        <LinearLayout         android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_weight="1"        android:orientation="vertical"        >                <TextView        android:id="@+id/title"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="Large Text"        android:padding="10dp"        android:textSize="20dp"        android:singleLine="true"        android:textAppearance="?android:attr/textAppearanceLarge" />    <TextView        android:id="@+id/textView3"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:padding="5dp"         />    <TextView        android:id="@+id/info"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="Large Text"        android:textSize="15dp"        android:lines="3"android:ellipsize="end"        android:textAppearance="?android:attr/textAppearanceLarge" />                    </LinearLayout>    <com.example.webview.ImageViewCircle        android:id="@+id/img"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:padding="20dp"        android:src="@drawable/ic_launcher" />    </LinearLayout>

4.主函数的适配器：ListViewAdapter.class

import java.util.ArrayList;import com.lidroid.xutils.BitmapUtils;import android.content.Context;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.ImageView;import android.widget.TextView;public class ListViewAdapter extends BaseAdapter {private Context context;private ArrayList<Info> list;public ListViewAdapter(Context context,ArrayList<Info> list){this.context=context;this.list=list;}@Overridepublic int getCount() {return list.size();}@Overridepublic Object getItem(int position) {return list.get(position);}@Overridepublic long getItemId(int position) {return position;}@Overridepublic View getView(int position, View convertView, ViewGroup parent) {ViewHolder holder;if(convertView==null){convertView = View.inflate(context, R.layout.listview_item, null);holder=new ViewHolder();holder.img = (ImageViewCircle) convertView.findViewById(R.id.img);holder.title = (TextView) convertView.findViewById(R.id.title);holder.info = (TextView) convertView.findViewById(R.id.info);convertView.setTag(holder);}else{holder = (ViewHolder) convertView.getTag();}holder.info.setText(list.get(position).getNewsinfo());holder.title.setText(list.get(position).getTitle());BitmapUtils bitmapUtils=new BitmapUtils(context);bitmapUtils.display(holder.img, list.get(position).getPic());return convertView;}class ViewHolder{TextView title,info;ImageViewCircle img;}}

5. WebActivity的布局：activity_web.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"  >   <WebView        android:layout_width="match_parent"        android:layout_height="match_parent"        android:id="@+id/webView" /></RelativeLayout>

6.实体类 Info.class

import java.io.Serializable;public class Info implements Serializable{private String title;private String newsinfo;private String pic;private String href;public String getTitle() {return title;}public void setTitle(String title) {this.title = title;}public String getNewsinfo() {return newsinfo;}public void setNewsinfo(String newsinfo) {this.newsinfo = newsinfo;}public String getPic() {return pic;}public void setPic(String pic) {this.pic = pic;}public String getHref() {return href;}public void setHref(String href) {this.href = href;}public Info(String title, String newsinfo, String pic, String href) {super();this.title = title;this.newsinfo = newsinfo;this.pic = pic;this.href = href;}public Info() {super();}@Overridepublic String toString() {return "Info [title=" + title + ", newsinfo=" + newsinfo + ", pic="+ pic + ", href=" + href + "]";}}

7.ImageViewCircle工具类

import android.annotation.SuppressLint;import android.content.Context;import android.graphics.Bitmap;import android.graphics.BitmapShader;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Matrix;import android.graphics.Paint;import android.graphics.Rect;import android.graphics.Shader.TileMode;import android.graphics.drawable.BitmapDrawable;import android.graphics.drawable.ColorDrawable;import android.graphics.drawable.Drawable;import android.util.AttributeSet;import android.widget.ImageView;public class ImageViewCircle extends ImageView {private Paint mPaintBitmap = new Paint(Paint.ANTI_ALIAS_FLAG);private Bitmap mRawBitmap;private BitmapShader mShader;private Matrix mMatrix = new Matrix();public ImageViewCircle(Context context, AttributeSet attrs, int defStyle) {super(context, attrs, defStyle);// TODO Auto-generated constructor stub}public ImageViewCircle(Context context, AttributeSet attrs) {super(context, attrs);// TODO Auto-generated constructor stub}public ImageViewCircle(Context context) {super(context);// TODO Auto-generated constructor stub}@Overrideprotected void onDraw(Canvas canvas) {Bitmap rawBitmap = getBitmap(getDrawable());if (rawBitmap != null){int viewWidth = getWidth();int viewHeight = getHeight();int viewMinSize = Math.min(viewWidth, viewHeight);float dstWidth = viewMinSize;float dstHeight = viewMinSize;if (mShader == null || !rawBitmap.equals(mRawBitmap)){mRawBitmap = rawBitmap;mShader = new BitmapShader(mRawBitmap, TileMode.CLAMP, TileMode.CLAMP);}if (mShader != null){mMatrix.setScale(dstWidth / rawBitmap.getWidth(), dstHeight / rawBitmap.getHeight());mShader.setLocalMatrix(mMatrix);}mPaintBitmap.setShader(mShader);float radius = viewMinSize / 2.0f;canvas.drawCircle(radius, radius, radius, mPaintBitmap);} else {super.onDraw(canvas);}}@SuppressLint("NewApi")private Bitmap getBitmap(Drawable drawable){if (drawable instanceof BitmapDrawable){return ((BitmapDrawable)drawable).getBitmap();} else if (drawable instanceof ColorDrawable){Rect rect = drawable.getBounds();int width = rect.right - rect.left;int height = rect.bottom - rect.top;int color = ((ColorDrawable)drawable).getColor();Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);Canvas canvas = new Canvas(bitmap);canvas.drawARGB(Color.alpha(color), Color.red(color), Color.green(color), Color.blue(color));return bitmap;} else {return null;}}}

8.WebActivity.class

import android.os.Bundle;import android.app.Activity;import android.content.Intent;import android.webkit.WebChromeClient;import android.webkit.WebView;public class WebActivity extends Activity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_web);        WebView webView = (WebView) findViewById(R.id.webView);Intent intent = getIntent();String path = intent.getStringExtra("path");webView.setWebChromeClient(new WebChromeClient());webView.loadUrl("http://www.cnbeta.com"+path);            }        }

最后别忘了配置网络权限。