SQLite_数据存储

1.SQLiets

package com.example.laji;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class Sql extends SQLiteOpenHelper{
    public Sql(Context context) {
        super(context, "user.db", null, 1);
    }

    @Override
    public void onCreate(SQLiteDatabase sqLiteDatabase) {
        sqLiteDatabase.execSQL("create table user(id integer primary key autoincrement," +
                "name text)");
    }

    @Override
    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {

    }
}

2.Dao_增查

package com.example.laji;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import java.util.ArrayList;
import java.util.List;
public class Dao {

    Sql sql ;
    SQLiteDatabase database;
    public Dao(Context context) {
         sql = new Sql(context);
         database = sql.getReadableDatabase();
    }
    public  void  add(String name){
        ContentValues values = new ContentValues();
        values.put("name",name);
        database.insert("user",null,values);
    }
    public List<UserBean> select(){
        List<UserBean> list = new ArrayList<>();
        UserBean userBean;
        Cursor query = database.query("user", null, null, null, null, null, null);
        while (query.moveToNext()){
            String name = query.getString(query.getColumnIndex("name"));
            userBean = new UserBean(name);
            list.add(userBean);
        }
        return list;
    }
}

3.UserBean

package com.example.laji;

public class UserBean {
    private String name;

    public UserBean(String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}