android sqlite 数据库创建及增删改查的操作实现

在android 开发工程中，我们经常会把数据保存到本地数据库，然后进行增删该查的操作，为了提高工作效率，近期我有空的时候稍微整理了一下，下面分享下

第一步首先定义下表中的列名，我们要建一个类 implements BaseColumns ,下面给出源码

/**
* Created by duanhongbo on 2016/11/28.
*/
public  class LocationData implements BaseColumns{
public static final String LOCATION_TABLE_NAME = "location"; // 表名
public static final String LOCATION_ID = "location_id";
public final static String LONGITUDE = "longitude"; // varchar 20 not
public final static String LATITUDE = "latitude"; // varchar 20 not null
public final static String ELEVATION = "elevation";// varchar 20 not
public final static String GsmSignalStrength = "gsmSignalStrength";// 信号强度
public final static String BatteryCount = "batteryCount";// 电量
public final static String GpsState = "gpsState";// gps开关
public final static String Time = "time";// 时间
public final static String UserId = "userid";// 用户idisNetwork
public final static String isNetwork = "isNetwork";// 是否联网

}

2  建一个数据库管理类  继承SQLiteOpenHelper，下面给出代码

/**
* Created by duanhongbo on 2016/11/28.
*/
public class DatabaseHelper extends SQLiteOpenHelper {
private static final String DATABASE_NAME = "transition.db";
private static final int DATABASE_VERSION = 1;
private Context context;
private static SQLiteDatabase mDb;
public synchronized SQLiteDatabase getInstence() {

if (null == mDb || (mDb != null && !mDb.isOpen())) {
mDb = getReadableDatabase();
//       mDb = getWritableDatabase();
}
return mDb;

}

public static synchronized void closeDB() {
if (null != mDb && mDb.isOpen()) {
mDb.close();
}
}

public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
// TODO Auto-generated constructor stub
this.context = context;
}
@Override
public void onCreate(SQLiteDatabase arg0) {
// TODO Auto-generated method stub
mDb = arg0;
/*
* 定位表
*/
mDb.execSQL("CREATE TABLE IF NOT EXISTS "
+ LocationData.LOCATION_TABLE_NAME + "( " + LocationData.LOCATION_ID
+ " INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL  , "
+ LocationData.LONGITUDE + " DOUBLE , " + LocationData.LATITUDE
+ " DOUBLE , " + LocationData.ELEVATION + " DOUBLE , "
+ LocationData.Time + " TEXT ," + LocationData.UserId + " TEXT ," + LocationData.GsmSignalStrength + " INTEGER , " + LocationData.BatteryCount + " INTEGER , " + LocationData.GpsState + " INTEGER ," + LocationData.isNetwork +" INTEGER );");
Log.i("dhb","success" + " -->  SUCCESS  ");
}
@Override
public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {
// TODO Auto-generated method stub

}

}

3第三部 我们要对数据库 进行增删该查的操作新建一个类LocationDao

/**
* Created by duanhongbo on 2016/11/28.
*/
public class LocationDao {
private DatabaseHelper dbHelper;

/**
*
*/
public LocationDao(Context context) {
// TODO Auto-generated constructor stub
this.dbHelper = new DatabaseHelper(context);
}

/*
* 插入某个用户的数据
*/
public int insertInfo(Loaction l) {

int success = 0;
boolean flag = false;
/*String sql = "SELECT  MAX(" + LocationData.Location.LOCATION_ID + ") from "
+ LocationData.Location.LOCATION_TABLE_NAME;*/
Cursor cursor = null;
SQLiteDatabase db = dbHelper.getInstence();
db.beginTransaction();//

try {
ContentValues contentValues = new ContentValues();
contentValues.put("elevation", l.getAltitude());//海拔
contentValues.put("latitude", l.getLatitude());//纬度
contentValues.put("longitude", l.getLongitude());//经度
contentValues.put("gsmSignalStrength", l.getGsmSignalStrength());//信号强度
contentValues.put("batteryCount", l.getBatteryCount());//电量
contentValues.put("gpsState", l.getGpsState() + "");//gps状态
contentValues.put("userid", l.getUserId());//用户id
contentValues.put("time", l.getTime());//定位时间
contentValues.put("isNetwork", l.getIsNetwork());//是否联网
long ok = db.insert(LocationData.LOCATION_TABLE_NAME, null,
contentValues);
if (0 < ok) {
flag = true;
} else {
flag = false;
}
db.setTransactionSuccessful();
} catch (Exception e) {
// TODO: handle exception
} finally {
db.endTransaction();
// db.close();
}
return success;
}

/**
* 删表某个用户的所有数据
*/
public boolean delTable(String userId) {
boolean isOk = false;
SQLiteDatabase db = dbHelper.getInstence();
db.beginTransaction();//
try {
int res = db.delete(LocationData.LOCATION_TABLE_NAME,
LocationData.UserId + "=?", new String[]{userId});
if (res > 0) {
isOk = true;

}
db.setTransactionSuccessful();

} catch (Exception e) {
e.printStackTrace();
} finally {
db.endTransaction();
}
return isOk;
}

/**
* 查询某个用户的所有数据
*
* @param userId
* @return
*/
public List<Loaction> getAllLocation(int userId) {
List<Loaction> allLoaction = new ArrayList<>();
Loaction l = null;
SQLiteDatabase db = dbHelper.getInstence();
db.beginTransaction();//
Cursor cursor = null;

String sql = "select * from " + LocationData.LOCATION_TABLE_NAME
+ " where " + LocationData.UserId + " = " + userId;
try {
cursor = db.rawQuery(sql, null);
while (cursor.moveToNext()) {
l = new Loaction();
String longtitude = cursor.getString(1);//经度
String latitude = cursor.getString(2);//纬度
String elevation = cursor.getString(3);//海拔
String time = cursor.getString(4);//时间
int userid = cursor.getInt(5);//用户id
int gsmSignalStrength = cursor.getInt(6);//信号强度
int batteryCount = cursor.getInt(7);//电量
int gpsState = cursor.getInt(8);//gps状态
int isNetwork= cursor.getInt(9);//是否联网

//............................................................................

l.setAltitude(Double.parseDouble(elevation));//海拔
l.setLongitude(Double.parseDouble(longtitude));//经度
l.setLatitude(Double.parseDouble(latitude));//纬度
l.setTime(time);//时间
l.setBatteryCount(batteryCount);//电量
l.setGsmSignalStrength(gsmSignalStrength);//强度
l.setUserId(userid);//用户id
l.setGpsState(gpsState);
l.setIsNetwork(isNetwork);
allLoaction.add(l);
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
db.endTransaction();
}
return allLoaction;
}

}

如果其他项目用到的话，适当修改就好了，谢谢，周五到了，要下班了。。。。。。。美好的周末即将到来