Android乐学成语

本文主要是介绍Android乐学成语，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

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。 