寒假打卡day25

今天做了什么

教程第五天

搭建数据库
Sqlite的运用是重难点
首先创建一个DBHelper类：按第四步的方法新建类，命名为：DBHelper

package com.example.myaccountapp;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

import androidx.annotation.Nullable;

public class DBHelper extends SQLiteOpenHelper {

private static int DB_VERSION = 1;
private static String DB_NAME = "account_daily.db";

public DBHelper(Context context) {
super(context, DB_NAME ,null, DB_VERSION);
}

@Override
public void onCreate(SQLiteDatabase db) {
String sql="create table account(_id integer primary key autoincrement," +//主键
"Title varchar(20)," +//Title
"Date varchar(20)," +//Date
"Money vaechar(20))";//Money
db.execSQL(sql);
}

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

}
}

然后我们写一个类专门存放赋值和取出这些数据的方法，命名为costList

package com.example.myaccountapp;

public class costList {
private String _id;
private String Title;
private String Date;
private String Money;

public String getMoney() {
return Money;
}

public void setMoney(String money) {
Money = money;
}

public String getDate() {
return Date;
}

public void setDate(String date) {
Date = date;
}

public String getTitle() {
return Title;
}

public void setTitle(String title) {
Title = title;
}

public String get_id() {
return _id;
}

public void set_id(String _id) {
this._id = _id;
}
}