greendao整理

//在项目的build.gradle中添加

dependencies {
   ...
    classpath 'org.greenrobot:greendao-gradle-plugin:3.2.0'
}
//在APP的build.gradle中添加

dependencies {
...
...
implementation 'org.greenrobot:greendao:3.2.0'//依赖
}
//添加
greendao {
    schemaVersion 1  //版本
    daoPackage 'com.bwie.xiongjinmeng.greendao' // 一般为app包名+生成文件的文件夹名自己建文件
    targetGenDir 'src/main/java' //生成文件路径
}

在apply plugin: 'com.android.application'的下面添加
apply plugin: 'org.greenrobot.greendao'

创建一个实体类

@Entity//标识
public class Shop {
    @Id(autoincrement = true)//自增
    private long id;//不能是int
    private String content;
    private String createTime;
    private String imgUrls;
    private String nickname;
}

 

//添加完   ctrl+F9或者点击锤子

//会自动在创建的文件夹中添加三个类

//在Application中初始化
public class App extends Application {
    public static DaoSession daoSession;

    @Override
    public void onCreate() {
        super.onCreate();
        setDatabase();
    }
    private void setDatabase() {
 //第一步创建OpenHelper类
    DaoMaster.DevOpenHelper openHelper = new DaoMaster.DevOpenHelper(this, "datalist.db");
    //开启一个可写数据库类
    SQLiteDatabase writableDatabase = openHelper.getWritableDatabase();
    //通过DaoMaster封装
    DaoMaster master = new DaoMaster(writableDatabase);
     daoSession = master.newSession();


}
public static DaoSession getDaoSession(){
    return daoSession;
}
}

//简单的添加查询

private QSLitertyDao dao;
dao = App.getDaoSession().getQSLitertyDao();
//插入数据
private void insertStu() {
    QSLiterty literty = new QSLiterty(null,"张三","中间");
    long insert = dao.insert(literty);
    if (insert>0){
        Toast.makeText(this, "成功", Toast.LENGTH_SHORT).show();
    }
}
//删除数据
private void deleteStu() {
    dao.deleteByKey(1l);
    Toast.makeText(this, "成功", Toast.LENGTH_SHORT).show();
}
//修改数据
private void updateStu() {
    QSLiterty load = dao.load(1l);
    if (load!=null){
        load.setName("李四");
        load.setSex("女");
        dao.update(load);
    }
}
//查询数据
private void selectStu() {
    textName.setText("");
    List<QSLiterty> qsLiterties = dao.loadAll();
    textName.setText(qsLiterties.toString());
}
//或者
public class ShopDao {

    public static void insertShop(Shop shop) {
        App.getDaoInstant().getShopDao().insertOrReplace(shop);
    }
    public static List<Shop> queryAll() {
        return App.getDaoInstant().getShopDao().loadAll();
    }

}

//使用添加

private Shop shop;
for (int j = 0; j < list.size(); j++) {
    shop = new Shop();
    shop.setContent(list.get(j).getContent());
    shop.setCreateTime(list.get(j).getCreateTime());
    shop.setNickname(list.get(j).getUser().getNickname());
    shop.setImgUrls(list.get(j).getImgUrls());
}
ShopDao.insert(shop);

android4.4以下版本中报错

java.lang.NoClassDefFoundError: org.greenrobot.greendao.database.StandardDatabase

添加依赖
implementation 'org.robolectric:multidex:3.4.2'
初始化时加
MultiDex.install(this);