An的roi的进阶之数据库操作

1、创建SQliteOpenHeplper子类。

2、建立数据库和表结构如下：版本号从1开始。底层以String类型存放

public class LocationInfosDBHelper extends SQLiteOpenHelper {

	private static final String DATABASE_NAME="gpsinfos.db";
	private static final int VERSION=1;
	public LocationInfosDBHelper(Context context
			) {
		super(context, <span style="color:#ff6666;">DATABASE_NAME</span>, null,<span style="color:#ff0000;"> VERSION</span>);
		// TODO Auto-generated constructor stub
	}

	@Override
	public void <span style="color:#ff6666;">onCreate</span>(SQLiteDatabase db) {
		db.execSQL("CREATE TABLE gpsinfos(_id integer primary key autoincrement,longitude TEXT,latitude TEXT, height TEXT)");
	}

	@Override
	public void<span style="color:#ff6666;"> onUpgrade</span>(SQLiteDatabase db, int oldVersion, int newVersion) {
		 db.execSQL("drop table gpsinfos   "  );
         onCreate(db);

	}

}

3、建立数据库操作规范，dao（子类和父类有公用方法就用抽象类，不然就用接口）

public interface DeviceMacAddressDao {
	/**
	 * 把excel中的读入内存的数据并写入数据库中
	 * @param info
	 */
	public void addDeviceMacInfo(MacInfo info);

	/**
	 * 清空设备mac地址和编号
	 */
	public void clearDeviceMacInfos();

	/**
	 * 清空设备mac地址和编号
	 * @param info 蓝牙信息实体
	 */
	public void deleteDeviceMacInfo(MacInfo info);

	/**
	 * 获得数据库中所有的蓝牙设备地址和编号
	 * @return
	 */
	public List<MacInfo> getAllMacInfos();

}
	

4、数据库表操作实现类

public class DeviceMacAddressDaoImpl implements DeviceMacAddressDao {
	private boolean D = true;
	private DeviceInfoDBHelper mDbHelper;

	public DeviceMacAddressDaoImpl(Context context) {
		mDbHelper = DeviceInfoDBHelper.getInstance(context);
	}

	@Override
	public void addDeviceMacInfo(MacInfo info) {
		SQLiteDatabase database = null;
		try {
			database = mDbHelper.getWritableDatabase();
			database.execSQL(
					"insert into DeviceMacAddress(device_num,device_mac)  values(?,?)",
					new String[] { info.getDeviceNumber(), info.getDeviceMac() });
			database.close();
		} catch (Exception e) {
			if (D) {
				Log.i("蓝牙mac地址", "蓝牙mac地址写入数据库失败!!!");
			}
		}
	}

...........

5、利用静态工厂获得数据库操作对象类似

/**
	 * 获得对蓝牙地址信息操作实例
	 *
	 * @param context
	 * @return
	 */
	public static synchronized DeviceMacAddressDao getDeviceMacAddressDao(Context context) {
		if (mDeviceMacAddressDao == null) {
			mDeviceMacAddressDao = new DeviceMacAddressDaoImpl(context);
		}
		return mDeviceMacAddressDao;

	}

使用数据库操作类进行数据操作时，选择合适的上下文，便于垃圾回收！！！可以使用软引用或软引用。