使用Zxing及豆瓣API

使用Zxing及豆瓣API | 疯狂的键盘

使用Zxing及豆瓣API

Posted on 2012/12/06

by Geek_Soledad

归档于 ANDROID

最近在做团队图书管理的一个Android端。因为需要通过手机扫描来输入图书信息（人工一条一条地输入，作为技术人员太受不了了），需要使用ZXing的API扫描图书ISBN，及使用豆瓣API来获取图书信息。

由于时间关系，这里没有使用ZXing的jar包，而是下载并安装了它的开源项目——条码扫描器，然后调用里面的Activity扫描再获取结果。
首先到市场下载Barcode Scaner（或搜索条码扫描器），下载安装。
下面先贴上Activity的布局代码，因为是demo版，而且在内部使用，就没去好好做布局设计，只是把需要的控件都写上。

<? 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 = "vertical" >

    < Button
        android:id = "@+id/home_scan"
        android:layout_width = "wrap_content"
        android:layout_height = "wrap_content"
        android:text = "@string/button_scan" />

    < TextView
        android:id = "@+id/home_result_scan"
        android:layout_width = "wrap_content"
        android:layout_height = "wrap_content" />

    < TextView
        android:id = "@+id/home_book_info"
        android:layout_width = "wrap_content"
        android:layout_height = "wrap_content" />

    < Button
        android:id = "@+id/home_upload_result"
        android:layout_width = "wrap_content"
        android:layout_height = "wrap_content"
        android:text = "@string/button_upload" />

    < TextView
        android:id = "@+id/home_result_upload"
        android:layout_width = "wrap_content"
        android:layout_height = "wrap_content"
        android:singleLine = "false" />

    < LinearLayout
        android:layout_width = "fill_parent"
        android:layout_height = "wrap_content" >

        < Button
            android:id = "@+id/home_borrow_book"
            android:layout_width = "wrap_content"
            android:layout_height = "wrap_content"
            android:text = "@string/borrow_book" />

        < Spinner
            android:id = "@+id/home_users"
            android:layout_width = "wrap_content"
            android:layout_height = "wrap_content"
            android:layout_gravity = "right" />
    </ LinearLayout >

    < Button
        android:id = "@+id/home_return_book"
        android:layout_width = "wrap_content"
        android:layout_height = "wrap_content"
        android:text = "@string/return_book" />

    < Button
        android:id = "@+id/home_user_manager"
        android:layout_width = "wrap_content"
        android:text = "@string/manager_user"
        android:layout_height = "wrap_content" />

</ LinearLayout >

然后在我们的项目中，写一个Activity来调用Zxing的扫描功能，并通过它返回的结果访问互联网获取信息。

下面是该Activity的代码。这里对于控件及事件的绑定，我使用了自己封装的一个工具（Androidkit)来简化这些代码，所以你们会看到许多类似@AndroidView的注解，这个工具可以在http://code.google.com/p/cfuture-androidkit/获取，或从https://github.com/msdx/androidkit上获得最新代码。

/*
 * @(#)HomeActivity.java               Project:bookscan
 * Date:2012-12-3
 *
 * Copyright (c) 2011 CFuture09, Institute of Software,
 * Guangdong Ocean University, Zhanjiang, GuangDong, China.
 * All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.sinaapp.msdxblog.bookscan.activity;

import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.widget.SimpleCursorAdapter;
import android.widget.Spinner;
import android.widget.TextView;

import com.sinaapp.msdxblog.androidkit.thread.HandlerFactory;
import com.sinaapp.msdxblog.androidkit.ui.ResBindUtil;
import com.sinaapp.msdxblog.androidkit.ui.UIBindUtil;
import com.sinaapp.msdxblog.androidkit.ui.annotation.AndroidRes;
import com.sinaapp.msdxblog.androidkit.ui.annotation.AndroidRes.ResType;
import com.sinaapp.msdxblog.androidkit.ui.annotation.AndroidView;
import com.sinaapp.msdxblog.androidkit.ui.annotation.OnClick;
import com.sinaapp.msdxblog.bookscan.R;
import com.sinaapp.msdxblog.bookscan.bean.Book;
import com.sinaapp.msdxblog.bookscan.util.DB;
import com.sinaapp.msdxblog.bookscan.util.XMLSax;

/**
 * @author Geek_Soledad ([email protected])
 */
public class HomeActivity extends Activity {
    private static final int HOME_ACTIVITY = 1990 ;
    private static final String DOUBAN_API = "http://api.douban.com/book/subject/isbn/" ;

    @AndroidView (id = R.id.home_result_scan)
    private TextView mTextScan;
    @AndroidView (id = R.id.home_book_info)
    private TextView mTextBook;
    @AndroidView (id = R.id.home_result_upload)
    private TextView mTextUpload;
    @AndroidView (id = R.id.home_users)
    private Spinner mSpinnerUser;

    @AndroidRes (id = R.string.result_scan, type = ResType.STRING)
    private String mStringScan;
    @AndroidRes (id = R.string.result_getting, type = ResType.STRING)
    private String mStringGetting;
    @AndroidRes (id = R.string.book_info, type = ResType.STRING)
    private String mStringBookInfo;

    private Handler mGettingBook;
    private Book book;
    private DB mDb;
    private SimpleCursorAdapter mAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super .onCreate(savedInstanceState);
        UIBindUtil.bind( this , R.layout.activity_home);
        ResBindUtil.bindAllRes( this );
        init();
    }

    /**
     * 初始化参数。
     */
    private final void init() {
        mGettingBook = HandlerFactory.getNewHandlerInOtherThread( "book" );
        mDb = new DB( this );
        Cursor users = mDb.getAllUser();
        startManagingCursor(users);
        mAdapter = new SimpleCursorAdapter( this ,
                android.R.layout.simple_spinner_item, users,
                new String[] { "username" }, new int [] { android.R.id.text1 });
        mAdapter
        .setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        mSpinnerUser.setAdapter(mAdapter);

    }

    @OnClick (viewId = { R.id.home_scan, R.id.home_upload_result,
            R.id.home_borrow_book, R.id.home_return_book,
            R.id.home_user_manager })
    public void onButtonClick(View v) {
        switch (v.getId()) {
        case R.id.home_scan:
            Intent intent = new Intent( "com.google.zxing.client.android.SCAN" );
            this .startActivityForResult(intent, HOME_ACTIVITY);
            break ;
        case R.id.home_upload_result:
            break ;
        case R.id.home_borrow_book:
            break ;
        case R.id.home_return_book:
            break ;
        case R.id.home_user_manager:
            startActivity( new Intent( this , UserManagerActivity. class ));
            break ;
        default :
            break ;
        }
    }

    @Override
    protected void onActivityResult( int requestCode, int resultCode, Intent data) {
        if (requestCode != HOME_ACTIVITY) {
            super .onActivityResult(requestCode, resultCode, data);
            return ;
        }
        if (data == null ) {
            return ;
        }
        final String isbn = data.getStringExtra( "SCAN_RESULT" );
        mTextScan.setText(String.format(mStringScan, isbn));
        if (isbn != null ) {
            mTextBook.setText(mStringGetting);
            mGettingBook.post( new Runnable() {

                @Override
                public void run() {
                    DefaultHttpClient client = new DefaultHttpClient();
                    HttpGet request = new HttpGet(DOUBAN_API + isbn);
                    try {
                        HttpResponse response = client.execute(request);
                        book = XMLSax.sax(response.getEntity().getContent());
                        String summary = book.getSummary();
                        summary = summary.substring( 0 ,
                                summary.length() < 60 ? summary.length() : 60 )
                                .concat( "..." );
                        String string = String.format(mStringBookInfo,
                                book.getName(), book.getAuthor(),
                                book.getPublisher(), book.getIsbn13(), summary);
                        updateBookInfoView(string);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }

            });
        }
    }

    /**
     * 更新图书信息
     *
     * @param string
     */
    private void updateBookInfoView( final String string) {
        runOnUiThread( new Runnable() {
            @Override
            public void run() {
                mTextBook.setText(string);
            }
        });
    }

    @Override
    protected void onResume() {
        super .onResume();
        mAdapter.notifyDataSetChanged();
    }

    @Override
    protected void onDestroy() {
        super .onDestroy();
        mDb.close();
    }
}

里面的功能及流程大致如下：
调用Zxinig的扫描条码的Activity，然后返回该扫描结果，显示扫描结果，然后调用豆瓣的API获取图书信息。接下来是要从我们的服务器上获得该图书的信息（如是否登记，有没有人借走等），但因为服务端还没搭建好，这一部分功能就没去实现。
上面代码中，调用Zxing的过程比较简单，

Intent intent = new Intent( "com.google.zxing.client.android.SCAN" );
this .startActivityForResult(intent, HOME_ACTIVITY);

然后再在onActivityResult方法中对返回的结果进行处理就好了。
然后从豆瓣API中获得的是xml格式的内容，这里我就使用了android自带的pull解析器。我需要获得的图书信息相对较少，Book的JavaBean如下：

/*
 * @(#)BookInfo.java               Project:bookscan
 * Date:2012-12-3
 *
 * Copyright (c) 2011 CFuture09, Institute of Software,
 * Guangdong Ocean University, Zhanjiang, GuangDong, China.
 * All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.sinaapp.msdxblog.bookscan.bean;

/**
 * @author Geek_Soledad ([email protected])
 */
public class Book {

    private String isbn10; // 10位的ISBN
    private String isbn13; // 13位的ISBN
    private String name; // 书名
    private String author; // 作者名
    private String summary; // 简介
    private String publisher; // 出版社
    private String image; // 封面图片地址

    public String getIsbn10() {
        return isbn10;
    }

    public void setIsbn10(String isbn10) {
        this .isbn10 = isbn10;
    }

    public String getIsbn13() {
        return isbn13;
    }

    public void setIsbn13(String isbn13) {
        this .isbn13 = isbn13;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this .name = name;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this .author = author;
    }

    public String getSummary() {
        return summary;
    }

    public void setSummary(String summary) {
        this .summary = summary;
    }

    public String getPublisher() {
        return publisher;
    }

    public void setPublisher(String publisher) {
        this .publisher = publisher;
    }

    public String getImage() {
        return image;
    }

    public void setImage(String image) {
        this .image = image;
    }

    @Override
    public String toString() {
        return "Book [isbn10=" + isbn10 + ", isbn13=" + isbn13 + ", name="
                + name + ", author=" + author + ", summary=" + summary
                + ", publisher=" + publisher + ", image=" + image + "]" ;
    }
}

然后解析器的代码如下：

/*
 * @(#)XMLSax.java             Project:bookscan
 * Date:2012-12-3
 *
 * Copyright (c) 2011 CFuture09, Institute of Software,
 * Guangdong Ocean University, Zhanjiang, GuangDong, China.
 * All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.sinaapp.msdxblog.bookscan.util;

import java.io.IOException;
import java.io.InputStream;

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

import com.sinaapp.msdxblog.bookscan.bean.Book;

import android.util.Log;
import android.util.Xml;

/**
 * @author Geek_Soledad ([email protected])
 */
public class XMLSax {

    public static Book sax(InputStream is) {
        Book book = null ;
        XmlPullParser parser = Xml.newPullParser();
        try {
            parser.setInput(is, "UTF-8" );
            int eventType = parser.getEventType();
            while (eventType != XmlPullParser.END_DOCUMENT) {
                switch (eventType) {
                case XmlPullParser.START_TAG:
                    Log.d( "test" , parser.getName());
                    if (parser.getName().equals( "entry" )) {
                        book = new Book();
                    } else if (parser.getName().equals( "link" )) {
                        if (parser.getAttributeValue( null , "rel" ).equals( "image" )) {
                            book.setImage(parser.getAttributeValue( null , "href" ));
                        }
                        eventType = parser.next();
                    }
                    else if (parser.getName().equals( "attribute" )) {
                        String attribute = parser.getAttributeValue( 0 );
                        eventType = parser.next();
                        if (attribute.equals( "title" )) {
                            book.setName(parser.getText());
                        } else if (attribute.equals( "author" )) {
                            book.setAuthor(parser.getText());
                        } else if (attribute.equals( "isbn10" )) {
                            book.setIsbn10(parser.getText());
                        } else if (attribute.equals( "isbn13" )) {
                            book.setIsbn13(parser.getText());
                        } else if ( attribute.equals( "publisher" )) {
                            book.setPublisher(parser.getText());
                        }
                    } else if (parser.getName().equals( "summary" )) {
                        eventType = parser.next();
                        book.setSummary(parser.getText());
                    } else if (parser.getName().equals( "title" )) {
                        if (book.getName() == null ) {
                            eventType = parser.next();
                            book.setName(parser.getText());
                        }
                    }
                    break ;
                case XmlPullParser.END_TAG:
                    break ;
                }
                eventType = parser.next();
            }

        } catch (XmlPullParserException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return book;
    }
}

然后是引用到的String资源，如下：

< resources >

    < string name = "app_name" >图书扫描</ string >
    < string name = "bookmark_picker_name" >Bookmarks</ string >
    < string name = "button_scan" >图书扫描</ string >
    < string name = "button_upload" >上传结果</ string >
    < string name = "result_scan" >扫描结果为：%s</ string >
    < string name = "result_getting" >正在向豆瓣请求数据</ string >
    < string name = "book_info" >图书信息：\n\t书名：%1$s\n\t作者：%2$s\n\t出版社：%3$s\n\tISBN：%4$s\n\t简介：%5$s </ string >
    < string name = "borrow_book" >借书</ string >
    < string name = "return_book" >还书</ string >
    < string name = "manager_user" >管理用户</ string >
    < string name = "add" >添加</ string >
    < string name = "delete" >删除</ string >
</ resources >

最后的结果是这样子的：