Android---sqlite基本操作

package com.xiangqiao.sqlite3;    import android.app.Activity;  import android.content.ContentValues;  import android.database.Cursor;  import android.database.sqlite.SQLiteDatabase;  import android.os.Bundle;  import android.view.View;  import android.view.View.OnClickListener;  import android.widget.Button;    public class MainActivity extends Activity {         Button createDatabase=null;   Button upgradeDatabase=null;   Button insert=null;   Button delete=null;   Button update=null;   Button query=null;      @Override      public void onCreate(Bundle savedInstanceState) {          super.onCreate(savedInstanceState);          setContentView(R.layout.main);                    createDatabase=(Button)findViewById(R.id.create);          createDatabase.setOnClickListener(listener);          upgradeDatabase=(Button)findViewById(R.id.updatabse);          upgradeDatabase.setOnClickListener(listener);          insert=(Button)findViewById(R.id.insert);          insert.setOnClickListener(listener);           delete=(Button)findViewById(R.id.delete);           delete.setOnClickListener(listener);          update=(Button)findViewById(R.id.update);          update.setOnClickListener(listener);          query=(Button)findViewById(R.id.query);          query.setOnClickListener(listener);      }            private OnClickListener listener=new OnClickListener() {        @Override    public void onClick(View v) {     Button button=(Button)v;       //创建数据库     if(v.getId()==R.id.create){       SQLiteHelper sqLiteHelper=new SQLiteHelper(MainActivity.this,"xiangqiao");       sqLiteHelper.getWritableDatabase();     }      //升级数据库     if(v.getId()==R.id.updatabse){      System.out.println("---------------");;      SQLiteHelper sqLiteHelper=new SQLiteHelper(MainActivity.this,"xiangqiao",2);       sqLiteHelper.getWritableDatabase();     }      //增     if(v.getId()==R.id.insert){      SQLiteHelper sqLiteHelper=new SQLiteHelper(MainActivity.this,"xiangqiao");       SQLiteDatabase sqLiteDatabase=sqLiteHelper.getWritableDatabase();              ContentValues values=new ContentValues();      values.put("id", 1);               values.put("name", "xiangqiao");              sqLiteDatabase.insert("user", null, values);     }      //删     if(v.getId()==R.id.delete){      SQLiteHelper sqLiteHelper=new SQLiteHelper(MainActivity.this,"xiangqiao");       SQLiteDatabase sqLiteDatabase=sqLiteHelper.getWritableDatabase();              sqLiteDatabase.delete("user", "id=?", new String[]{"1"});     }      //改     if(v.getId()==R.id.update){      SQLiteHelper sqLiteHelper=new SQLiteHelper(MainActivity.this,"xiangqiao");       SQLiteDatabase sqLiteDatabase=sqLiteHelper.getWritableDatabase();              ContentValues values=new ContentValues();                values.put("name", "xiangqiaoqiao");       sqLiteDatabase.update("user", values, "id=?", new String[]{"1"});     }      //查     if(v.getId()==R.id.query){      SQLiteHelper sqLiteHelper=new SQLiteHelper(MainActivity.this,"xiangqiao");       SQLiteDatabase sqLiteDatabase=sqLiteHelper.getWritableDatabase();             Cursor cursor=sqLiteDatabase.query("user", new String []{"id","name"}, "id=?", new String []{"1"}, "", "", "");      while(cursor.moveToNext()){       String name=cursor.getString(cursor.getColumnIndex("name"));       System.out.println("------->"+name);      }     }         }   };  }

package com.xiangqiao.sqlite3;    import android.content.Context;  import android.database.sqlite.SQLiteDatabase;  import android.database.sqlite.SQLiteOpenHelper;  import android.database.sqlite.SQLiteDatabase.CursorFactory;    public class SQLiteHelper extends SQLiteOpenHelper {     private static int version=1;    public SQLiteHelper(Context context, String name, CursorFactory factory,     int version) {    super(context, name, factory, version);   }   public SQLiteHelper(Context context, String name) {    this(context, name, version);   }   public SQLiteHelper(Context context, String name,     int version) {     this(context, name, null, version);   }   @Override   public void onCreate(SQLiteDatabase db) {    db.execSQL("create table user (id int,name string)");          System.out.println("create  database table");   }     @Override   public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {     System.out.println("upgrade  database ");   }    }