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。
