Category_5/MyApplication.java

package com.example;

import android.app.Application;
import android.database.sqlite.SQLiteDatabase;

import com.example.greendao.DaoMaster;
import com.example.greendao.DaoSession;




public class MyApplication extends Application {
    private static DaoSession daoSession;
    private static MyApplication instance;

    @Override
    public void onCreate() {
        super.onCreate();
        instance = this;
        //必须调用初始化

        //配置数据库
        setupDatabase();
    }

    public static MyApplication getInstance() {
        return instance;
    }

    /**
     * 配置数据库
     */
    private void setupDatabase() {
        //创建数据库shop.db"
        DaoMaster.DevOpenHelper helper = new DaoMaster.DevOpenHelper(this, "shop.db", null);
        //获取可写数据库
        SQLiteDatabase db = helper.getWritableDatabase();
        // 获取数据库对象
        DaoMaster daoMaster = new DaoMaster(db);
        // 获取Dao对象管理者
        daoSession = daoMaster.newSession();
    }

    public static DaoSession getDaoInstant() {
        return daoSession;
    }

}