Android乐学成语

效果图

具体实现以及写的过程中遇到的问题

第一步：建立数据库，像这种比较繁多的数据，可以用execl表格来做，然后Navict可视化工具，导入进去

加载数据数据库到项目中来，在res目录下建立一个raw文件夹，

DBOpenHelper.java

package cn.bzu.bztc.happyidiom.db;

 

import java.io.File;

import java.io.FileOutputStream;

import java.io.InputStream;

 

import cn.bzu.bztc.happyidiom.activity.R;

import android.content.Context;

import android.database.sqlite.SQLiteDatabase;

import android.os.Environment;

 

public class DBOpenHelper {

    private final int BuFFWER_SIZE=400000;//缓冲区大小

    public static final String DB_NAME="idioms.db";//保存的数据库文件名

    public static final String PACKAGE_Name="cn.deu.bztc.happyidiom.activity";

    //应用的包名

    public static final String DB_PATH="/data"

            +Environment.getDataDirectory().getAbsolutePath()+"/"

            +PACKAGE_Name+"/databases";//在手机里存放数据库的位置

    private Context context;

    public DBOpenHelper(Context context) {

        super();

        this.context = context;

    }

    public SQLiteDatabase openDatabase(){

        try{

            File myDataPath=new File(DB_PATH);

            if(!myDataPath.exists()){

                myDataPath.mkdirs(); //如果没有这个目录则创建

            }

            String dbfile=myDataPath+"/"+DB_NAME;

            if(!(new File(dbfile).exists())){

                //判断数据库文件是否存在，若不存在则执行导入，否则直接打开数据库

                InputStream is=context.getResources().openRawResource(R.raw.idioms);

                FileOutputStream fos=new FileOutputStream(dbfile);

                byte[] buffer=new byte[BuFFWER_SIZE];

                int count=0;

                while((count=is.read(buffer))>0){

                    fos.write(buffer, 0, count);

                }

                fos.close();

                is.close();

            }

            SQLiteDatabase db=SQLiteDatabase.openOrCreateDatabase(dbfile, null);

            return db;

        }catch (Exception e) {

            // TODO: handle exception

            e.printStackTrace();

        }

        return null;

    }

}

上面的代码实现功能主要是使用输入输出流将idioms.db复制到手机中默认存放 数据库的位置

在test包下建立DBOpenHelpTest.java（链接测试）

package cn.deu.bztc.happyidiom.test;

 

import java.util.List;

 

import cn.bzu.bztc.happyidiom.dao.AnimalDao;

import cn.bzu.bztc.happyidiom.db.DBOpenHelper;

import cn.bzu.bztc.happyidiom.entity.Animal;

import android.test.AndroidTestCase;

 

public class DBOpenHelpTest extends AndroidTestCase {

    public void testDBCOpy(){

        DBOpenHelper  dbopenHelper=new DBOpenHelper(getContext());

        dbopenHelper.openDatabase();

    }

    public void testGetAllAnimals(){

        AnimalDao animalDao=AnimalDao.getInstance(getContext());

        List animals=animalDao.getAllAnimals();

        System.out.println(animals.size());

        for(Animal animal:animals){

            System.out.println(animal.getName());

        }

    }

}

然后你会发现在raw目录下多个数据库

happyidiom.entity建立实体类

public class Animal {

    private int id; 

    private String name;//成语名称

    private String pronounce;//成语发音

    private String explain;//成语解释

    private String antonym;//反义词

    private String homoionym;//同义词

    private String derivation;//源自

    private String examples;//例子

    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 String getPronounce() {

        return pronounce;

    }

    public void setPronounce(String pronounce) {

        this.pronounce = pronounce;

    }

    public String getExplain() {

        return explain;

    }

    public void setExplain(String explain) {

        this.explain = explain;

    }

    public String getAntonym() {

        return antonym;

    }

    public void setAntonym(String antonym) {

        this.antonym = antonym;

    }

    public String getHomoionym() {

        return homoionym;

    }

    public void setHomoionym(String homoionym) {

        this.homoionym = homoionym;

    }

    public String getDerivation() {

        return derivation;

    }

    public void setDerivation(String derivation) {

        this.derivation = derivation;

    }

    public String getExamples() {

        return examples;

    }

    public void setExamples(String examples) {

        this.examples = examples;

    }

     

}

然后在数据库管理层 （Dao 层）建立操作类AnimalDao.java

public class AnimalDao {

    private static AnimalDao animalDao;

    private static SQLiteDatabase db;

    /**

     * 将构造方法私有化

     */

    public AnimalDao(Context  context) {

        DBOpenHelper dbHelper=new DBOpenHelper(context);

        db=dbHelper.openDatabase();

    }

    /**

     * 获取AnimalDao实例

     */

    public synchronized static AnimalDao getInstance(Context context){

        if(animalDao==null){

            animalDao=new AnimalDao(context);

        }

        return animalDao;

    }

    /**

     * 从数据库读取所有的动物类成语

     */

    public static  List getAllAnimals(){

        List list=new ArrayList();

        Cursor cursor=db.query("animal", null, null, null, null,null,null);

        if(cursor.moveToFirst()){

            do{

                Animal animal=new Animal();

                animal.setId(cursor.getInt(cursor.getColumnIndex("_id")));

                animal.setName(cursor.getString(cursor.getColumnIndex("name")));

                animal.setPronounce(cursor.getString(cursor.getColumnIndex("pronounce")));

                animal.setAntonym(cursor.getString(cursor.getColumnIndex("antonym")));

                animal.setHomoionym(cursor.getString(cursor.getColumnIndex("homoionym")));

                animal.setDerivation(cursor.getString(cursor.getColumnIndex("derivation")));

                animal.setExamples(cursor.getString(cursor.getColumnIndex("examples")));

                list.add(animal);

            }while(cursor.moveToNext());

        }

        return list;

    }

}

下面进行单元测试,如下

UI界面

然后在res的values目录的string.xml文件中定义

<string-array name="category">

       <item>动物类</item>

       <item>自然类</item>

       <item>人物类</item>

       <item>季节类</item>

       <item>数字类</item>

       <item>寓言类</item>

       <item>其他类</item>

</string-array>

happyidiom.activity中建立MainActivity.java

public class MainActivity extends TabActivity {

    private TabHost  tabHost;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        requestWindowFeature(Window.FEATURE_NO_TITLE);//取消标题栏

        setContentView(R.layout.activity_main);

        tabHost=getTabHost();

        addTab("study", R.string.title_study, R.drawable.study,StudyActivity.class);

        addTab("search", R.string.title_search, R.drawable.search, StudyActivity.class);

        addTab("study", R.string.title_game, R.drawable.game, StudyActivity.class);

        addTab("save", R.string.title_save, R.drawable.save, StudyActivity.class);

        addTab("help", R.string.title_help, R.drawable.search, StudyActivity.class);

    }

    private void addTab(String tag,int title_introduction,int title_icon,Class ActivityClass){

        tabHost.addTab(tabHost.newTabSpec(tag)

                .setIndicator(getString(title_introduction),

                        getResources().getDrawable(title_icon)).setContent(new Intent(this,ActivityClass)));

    }

     

    @Override

    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.

        getMenuInflater().inflate(R.menu.main, menu);

        return true;

    }

 

}

在这个类里调用TabHost组件， 然后调用了抽取出来的自定义的方法addTob()添加了五个选项卡，方法的四个参数分别为每个选项卡的tag，指示器上显示的标题。，指示器上显示的图片，选项卡对应的内容。