十天冲刺

今天又系统学习了安卓开发数据库Sqlite的相关知识，相关api操作数据库的具体写法：

学习视频https://www.bilibili.com/video/BV1wt411n7pz?from=search&seid=5602890916190660679

按照up主的视频一步步掌握其使用方法

package com.example.myapplicationgb;


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

import androidx.annotation.Nullable;

public class DatabaseHelper extends SQLiteOpenHelper {

    public static final String COST_MONEY = "cost_money";
    public static final String COST_DATE = "cost_date";
    public static final String COST_TITLE = "cost_title";
    public static final String FAMILY_BILL = "family_bill";

    public DatabaseHelper(@Nullable Context context) {
        super(context, "family_bill", null, 2);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("create table if not exists family_bill(" +
                "id integer primary key, " +
                "cost_title varchar, "+
                "cost_date varchar, "+
                "cost_money varchar)");
    }

    public void insertCost(CostBean costBean){
        SQLiteDatabase database = getWritableDatabase();
        ContentValues cv = new ContentValues();
        cv.put(COST_TITLE,costBean.costTitle);
        cv.put(COST_DATE,costBean.costDate);
        cv.put(COST_MONEY,costBean.costMoney);
        database.insert(FAMILY_BILL,null,cv);
    }

    public Cursor getAllCostData(){
        SQLiteDatabase database = getWritableDatabase();
        return database.query(FAMILY_BILL,null,null,null,null,null,"COST_DATE ASC");
    }

    public void deleteOne(CostBean costBean)
    {
        SQLiteDatabase database=getWritableDatabase();
        database.delete(FAMILY_BILL,"COST_TITLE = ? and COST_MONEY = ? and COST_DATE = ?", new String[]{""+costBean.costTitle,""+costBean.costMoney,""+costBean.costDate});
    }
    public  Cursor selectlist(String s){
        SQLiteDatabase database =getWritableDatabase();
//        String sql = "select * from "+ FAMILY_BILL +"where cost_date = '%"+s+"%' ";
//        database.execSQL(sql);
//        database.close();
        return database.query(FAMILY_BILL,null,"cost_date LIKE ?",new String[]{"%"+s+"%"},null,null,"COST_DATE ASC");
    }
    public void deleteAllData(){
        SQLiteDatabase database = getWritableDatabase();
        database.delete(FAMILY_BILL,null,null);
    }


    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    }
}

 我在团队中的任务是编写可视化显示数据。