android:SQLiteOpenHelper 与 greenDao 数据库操作
原文地址:http://blog.csdn.net/intbird
项目里使用的是greeDao,sqllite是以前练习使用的,
如果项目里全用这个,人会比较累;
然而greenDao使用起来非常方便,可以说是三分钟速成
如不明白请看官方文档,源码里也有详细说明.
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@GreenDao
官网链接:http://greendao-orm.com/documentation/how-to-get-started/
官网DEMO:https://github.com/greenrobot/greenDAO
public static void save(Locations locs) { SQLiteDatabase db = Frame.getInstance().getDbHelp().getWritableDatabase(); DaoMaster master = new DaoMaster(db); DaoSession session = master.newSession(); DbLocationsDao locsDao = session.getDbLocationsDao(); locsDao.insertOrReplace(locs); ; db.close(); } public static void deletedFromLast(long lastId){ SQLiteDatabase db = Frame.getInstance().getDbHelp().getWritableDatabase(); DaoMaster master = new DaoMaster(db); DaoSession session = master.newSession(); DbLocationsDao locsDao = session.getDbLocationsDao(); QueryBuilder<DbLocations> query = locsDao.queryBuilder(); DeleteQuery<DbLocations> delete = query.where(Properties.Time.le(lastId)).buildDelete(); delete.executeDeleteWithoutDetachingEntities(); db.close(); } public static long getDbSize(){ SQLiteDatabase db = Frame.getInstance().getDbHelp().getWritableDatabase(); DaoMaster master = new DaoMaster(db); DaoSession session = master.newSession(); DbLocationsDao locsDao = session.getDbLocationsDao(); long size = locsDao.queryBuilder().count(); return size; } public static List<DbLocations> getDataBySize(int size){ SQLiteDatabase db = Frame.getInstance().getDbHelp().getWritableDatabase(); DaoMaster master = new DaoMaster(db); DaoSession session = master.newSession(); DbLocationsDao locsDao = session.getDbLocationsDao(); List<DbLocations> list = locsDao.queryBuilder().limit(size).orderAsc(Properties.Time).build().list(); db.close(); return list; }============
@SqlLiteOpenHelper
例子
package mode; import java.util.ArrayList; import java.util.HashMap; import java.util.Map; import core.override.MyselfDishAdapter; import android.content.ContentValues; import android.content.Context; import android.database.Cursor; import android.database.sqlite.*; public class DishSqlite extends SQLiteOpenHelper { private static final String TB_NAME = "tb_dishMode"; private static final String CREATE_TABLE_SQL = "create table "+TB_NAME+"(" + DishMode.ds_id+" integer primary key autoincrement," + DishMode.ds_name+" text," + DishMode.ds_cover+" text," + DishMode.ds_img+ " text," + DishMode.ds_tips+ " text," + DishMode.ds_addTime+ " text)"; public DishSqlite(Context context) { super(context, TB_NAME, null, 1); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(CREATE_TABLE_SQL); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // db.execSQL("ALTER TABLE tb_student ADD COLUMN other STRING"); // SCHMA_VERSION } public void executeSql(String sql) { this.getWritableDatabase().execSQL(sql); this.getWritableDatabase().close(); } /** ** 查询 **/ public ArrayList<Map<String,String>> getAllDataInDB(String state) { ArrayList<Map<String,String>> listmap = new ArrayList<Map<String,String>>(); Cursor cur = getWritableDatabase().query(TB_NAME, null, null, null, null, null, null);// 查询并获得游标 if (cur.moveToFirst()) {// 判断游标是否为空 do { Map<String,String> map=new HashMap<String, String>(); int id = cur.getInt(cur.getColumnIndex(DishMode.ds_id )); String statedb=cur.getString(cur.getColumnIndex(DishMode.ds_state)); if(statedb.equals(state)){ String name=cur.getString(cur.getColumnIndex(DishMode.ds_name)); String dishCover=cur.getString(cur.getColumnIndex(DishMode.ds_cover)); String dishTime=cur.getString(cur.getColumnIndex(DishMode.ds_addTime)); map.put("id", id+""); map.put("style", MyselfDishAdapter.styleNormal+""); map.put("name", name); map.put("img", dishCover); map.put("addTime", dishTime); listmap.add(map); } } while (cur.moveToNext()); cur.close(); this.getWritableDatabase().close(); } return listmap; } /** * 插入一条数据; */ public int insert(DishMode upData) { ContentValues cv = new ContentValues(); cv.put(DishMode.ds_name, upData.getName()); cv.put(DishMode.ds_cover, upData.getCover()); cv.put(DishMode.ds_img, upData.getImg()); cv.put(DishMode.ds_state, upData.getState()); cv.put(DishMode.ds_burden, upData.getBurden()); cv.put(DishMode.ds_makes, upData.getMakes()); cv.put(DishMode.ds_tips, upData.getTips()); cv.put(DishMode.ds_addTime, upData.getAddTime()); long id = this.getWritableDatabase().insert(TB_NAME, null, cv); this.getWritableDatabase().close(); return (int)id; } /** * 修改一条数据; */ public int update(DishMode upData) { ContentValues cv = new ContentValues(); cv.put(DishMode.ds_name, upData.getName()); cv.put(DishMode.ds_cover, upData.getCover()); cv.put(DishMode.ds_img, upData.getImg()); cv.put(DishMode.ds_state, upData.getState()); cv.put(DishMode.ds_burden, upData.getBurden()); cv.put(DishMode.ds_makes, upData.getMakes()); cv.put(DishMode.ds_tips, upData.getTips()); cv.put(DishMode.ds_addTime, upData.getAddTime()); int row= this.getWritableDatabase().update(TB_NAME, cv,null,null); this.getWritableDatabase().close(); return row; } /** * 删除 */ public boolean deleteById(int id) { int i = this.getWritableDatabase().delete(TB_NAME, DishMode.ds_id+"=" + Integer.valueOf(id) + "", null); this.getWritableDatabase().close(); if (i > 0) return true; else return false; }
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