使用Zxing及豆瓣API

Posted on 2012/12/06

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。

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/*
 * @(#)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 (66704238@51uc.com)
 */
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，

1 2	`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 (66704238@51uc.com)
 */
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 (66704238@51uc.com)
 */
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：