Android——LitePal

    implementation 'org.litepal.android:java:3.0.0'

1. 修改AndroidManifest.xml 

android:name="org.litepal.LitePalApplication"

2. main包下生成assets文件夹，并创建litepal.xml

<?xml version="1.0" encoding="utf-8" ?>
<litepal>
<!--   数据库名 -->
    <dbname value="weather.db"/>
<!--   版本号 -->
    <version value="1"/>
<!--    和类映射的mapping文件，如果有多个实体类，那就写多个mapping-->
    <list>
<!--      mapping 映射 包名加上类全名  -->
        <mapping class="com.example.myandroiddemo.domain.Weather" />
<!--        <mapping class="com.example.myandroiddemo.domain.Data" />-->
    </list>
<!--    每更新一次数据库，版本号需要改变， +1-->
</litepal>

<!-- 
　　dbname设置数据库名称
　　version 设置版本号，修改表结构或者新增与删除表需要更改 version
　　list 里添加表
-->

3. 创建bean类，继承LitePalSupport

package com.example.myandroiddemo.domain;

import org.litepal.crud.LitePalSupport;

public class Weather extends LitePalSupport {
    private String date;
    private String temperature;
    private String weather;
    private String direct;



    public String getTemperature() {
        return temperature;
    }

    public void setTemperature(String temperature) {
        this.temperature = temperature;
    }

    public String getWeather() {
        return weather;
    }

    public void setWeather(String weather) {
        this.weather = weather;
    }

    public String getDirect() {
        return direct;
    }

    public void setDirect(String direct) {
        this.direct = direct;
    }

    public String getDate() {
        return date;
    }

    public void setDate(String date) {
        this.date = date;
    }

    @Override
    public String toString() {
        return "Weather{" +
                "date='" + date + '\'' +
                ", temperature='" + temperature + '\'' +
                ", weather='" + weather + '\'' +
                ", direct='" + direct + '\'' +
                '}';
    }
}

4. 在util包下生成：LiteHelper 暴露接口

package com.example.myandroiddemo.litepalManager;

import android.content.ContentValues;

import com.example.myandroiddemo.domain.Weather;

import org.litepal.LitePal;

import java.util.ArrayList;
import java.util.List;

public class LitePals {
    // 删除
    public static void deleteWeather(int id){
//        根据id删除
        LitePal.delete(Weather.class,id);
    }

    // 增加
    public static void addWeatherData(Weather weather){
        weather.save(); //继承的那个 ， 设置后直接save
    }

    //查询
    public static List<Weather> findAllWeatherData(){
//        List<Weather> list = new ArrayList<>();
        List<Weather> weatherList = LitePal.findAll(Weather.class);
//        for (int i = 0; i < list.size(); i++) {
//            list.add(weatherList.get(i));
//        }
        return weatherList;
    }

    //修改
    public static void updateWeatherData(int id){
        ContentValues contentValues = new ContentValues();
        LitePal.update(Weather.class,contentValues,id);
    }
}