Android记账本开发（三）：数据库开发

今天做了一些关于数据库的内容。

根据app功能，需要进行数据存储的无非三个方面：用户的个人信息、该用户的收入情况和支出情况，下面进行具体论述。

首先是用户的个人信息，初步设计账号密码功能，后续可能添加头像等。

然后是收入情况，可以先设计一个收入类型的列表，记录所有的收入类别，例如工资，奖金等，目的是为之后用户选择添加收入时提供添加选项。

然后是个人的收入记录，列表项有种类Category，金额Money，备注remark，日期date等。

支出状况类似。

首先定义DatabaseHelper.java类建立数据库。

package com.example.thorineaccount.db;

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

import com.example.thorineaccount.R;

import java.text.SimpleDateFormat;
import java.util.Date;

public class DatabaseHelper extends SQLiteOpenHelper {
    private static final String DATABASE_NAME = "account.db";
    private static final int DATABASE_VERSION = 1;
    public DatabaseHelper(Context context) {//修改构造方法
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {//启动程序时第一次创建，若程序已安装，需要先卸载
        // 建表
        //收入类别
        String sql = "CREATE table accountincometype (id integer primary key autoincrement,category text,icon integer)";
        db.execSQL(sql);
        //收入明细表(id,类别，金额，备注，日期时间)
        sql = "CREATE table accountincome (id integer primary key autoincrement,category text,"+
                "money double,remark text,date text)";
        db.execSQL(sql);

        //支出类别
        sql = "CREATE table accountoutlaytype (id integer primary key autoincrement,category text,icon integer)";
        db.execSQL(sql);
        //支出明细表(id,类别，金额，备注，日期时间)
        sql = "CREATE table accountoutlay (id integer primary key autoincrement,category text,"+
                "money double,remark text,date text)";
        db.execSQL(sql);

        //初始化的数据
        initData(db);
    }

    //自动增长的列表，不需要给值；某个字段不想给值，不出现在表名后的列表中
    private void initData(SQLiteDatabase db) {
        //收入类别
        String sql = String.format("insert into accountincometype(category,icon) values(‘工资‘,%d)", R.drawable.fund_icon);
        db.execSQL(sql);
        sql = String.format("insert into accountincometype(category,icon) values(‘奖金‘,%d)", R.drawable.insurance_icon);
        db.execSQL(sql);
        sql = String.format("insert into accountincometype(category,icon) values(‘兼职收入‘,%d)", R.drawable.baby_icon);
        db.execSQL(sql);

        //支出类别
        sql = String.format("insert into accountoutlaytype(category,icon) values(‘交通‘,%d)", R.drawable.traffic_icon);
        db.execSQL(sql);
        sql = String.format("insert into accountoutlaytype(category,icon) values(‘食物‘,%d)", R.drawable.breakfast_icon);
        db.execSQL(sql);
        sql = String.format("insert into accountoutlaytype(category,icon) values(‘图书‘,%d)", R.drawable.book_icon);
        db.execSQL(sql);
        sql = String.format("insert into accountoutlaytype(category,icon) values(‘电影‘,%d)", R.drawable.film_icon);
        db.execSQL(sql);
        sql = String.format("insert into accountoutlaytype(category,icon) values(‘房租‘,%d)", R.drawable.housing_loan_icon);
        db.execSQL(sql);
        sql = String.format("insert into accountoutlaytype(category,icon) values(‘运动‘,%d)", R.drawable.sport_icon);
        db.execSQL(sql);

        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        String currentDate = sdf.format(new Date());
        //收入明细
        sql = "insert into accountincome(category,money,date) values(‘工资‘,10000,‘"+currentDate+"‘)";
        db.execSQL(sql);
        sql = "insert into accountincome(category,money,date) values(‘奖金‘,1000,‘"+currentDate+"‘)";
        db.execSQL(sql);

        //支出明细
        sql = "insert into accountoutlay(category,money,date) values(‘交通‘,100,‘"+currentDate+"‘)";
        db.execSQL(sql);
        sql = "insert into accountoutlay(category,money,date) values(‘食物‘,200,‘"+currentDate+"‘)";
        db.execSQL(sql);
        sql = "insert into accountoutlay(category,money,date) values(‘图书‘,150,‘"+currentDate+"‘)";
        db.execSQL(sql);
        sql = "insert into accountoutlay(category,money,date) values(‘电影‘,100,‘"+currentDate+"‘)";
        db.execSQL(sql);
    }
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    }
}

收入数据表：accountincome

收入种类表：accountincometype

支出数据表：accountoutlay

支出种类表：accountoutlaytype

即完成数据表的基本创建。

编写AccountDao.java 文件

package com.example.thorineaccount.db;

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

import com.example.thorineaccount.entity.AccountCategory;
import com.example.thorineaccount.entity.AccountItem;

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

public class AccountDao {
    private DatabaseHelper helper;
    private SQLiteDatabase db;
    public AccountDao(Context context){
        //创建数据库
        helper = new DatabaseHelper(context);
        db = helper.getWritableDatabase();
    }

    //收入类型
    public List<AccountCategory> getIncomeType(){
        List<AccountCategory> result = new ArrayList<AccountCategory>();
        String sql = "select id,category,icon from AccountIncomeType";
        Cursor cursor = db.rawQuery(sql, null);
        while (cursor.moveToNext()){
            int id = cursor.getInt(cursor.getColumnIndex("id"));
            String category = cursor.getString(cursor.getColumnIndex("category"));
            int icon = cursor.getInt(cursor.getColumnIndex("icon"));
            AccountCategory c = new AccountCategory(id,category,icon);
            result.add(c);
        }
        cursor.close();
        return result;
    }

    //支出类型
    public List<AccountCategory> getOutlayType(){
        ArrayList<AccountCategory> result = new ArrayList<AccountCategory>();
        String sql = "select id,category,icon from AccountOutlayType";
        Cursor cursor = db.rawQuery(sql, null);
        while (cursor.moveToNext()){
            int id = cursor.getInt(cursor.getColumnIndex("id"));
            String category = cursor.getString(cursor.getColumnIndex("category"));
            int icon = cursor.getInt(cursor.getColumnIndex("icon"));
            AccountCategory c = new AccountCategory(id,category,icon);
            result.add(c);
        }
        cursor.close();
        return result;
    }

    public List<AccountItem> getIncomeList(){
        ArrayList<AccountItem> result = new ArrayList<>();
        Cursor cursor = db.query("AccountIncome",null,null,null,null,null,null);
        while (cursor.moveToNext()){//依次读取，将每次读取的对象加入集合中
            AccountItem item = new AccountItem();
            item.setId(cursor.getInt(cursor.getColumnIndex("id")));
            item.setCategory(cursor.getString(cursor.getColumnIndex("category")));
            item.setMoney(cursor.getDouble(cursor.getColumnIndex("money")));
            item.setDate(cursor.getString(cursor.getColumnIndex("date")));
            item.setRemark(cursor.getString(cursor.getColumnIndex("remark")));
            result.add(item);
        }
        cursor.close();
        return result;
    }

    //支出类型
    public List<AccountItem> getOutlayList(){
        ArrayList<AccountItem> result = new ArrayList<AccountItem>();
        String sql = "select id,category,money,remark,date from AccountOutlay";
        Cursor cursor = db.rawQuery(sql, null);
        while (cursor.moveToNext()){
            AccountItem item = new AccountItem();
            item.setId(cursor.getInt(cursor.getColumnIndex("id")));
            item.setCategory(cursor.getString(cursor.getColumnIndex("category")));
            item.setMoney(cursor.getDouble(cursor.getColumnIndex("money")));
            item.setDate(cursor.getString(cursor.getColumnIndex("date")));
            item.setRemark(cursor.getString(cursor.getColumnIndex("remark")));
            result.add(item);
        }
        cursor.close();
        return result;
    }

    public void addIncome(AccountItem item){
        db.beginTransaction();//开启事务
        try{
            db.execSQL("INSERT INTO AccountIncome(id,category,money,date,remark) VALUES(null,?,?,?,?)",new Object[]{item.getCategory(),item.getMoney(),item.getDate(), item.getRemark()});
            db.setTransactionSuccessful();
        }finally {
            db.endTransaction();//结束
        }
    }

    //添加支出
    public void addOutlay(AccountItem item) {
        db.beginTransaction();
        try {
            db.execSQL("INSERT INTO AccountOutlay(id,category,money,date,remark) VALUES(null,?,?,?,?)",
                    new Object[]{item.getCategory(), item.getMoney(),item.getDate(),item.getRemark()});

            db.setTransactionSuccessful();
        } finally {
            db.endTransaction();
        }
    }
    //删除收入
    public void deleteIncome(long id) {
        String sql = "delete from AccountIncome where id="+id;

        db.beginTransaction();
        try {
            db.execSQL(sql);
            db.setTransactionSuccessful();
        } finally {
            db.endTransaction();
        }

    }

    //添加收入类型
    public void addIncomeCategory(String category,int icon) {
        db.beginTransaction();
        try {
            db.execSQL("INSERT INTO AccountIncomeType(id,category,icon) VALUES(null,?,?)",
                    new Object[]{category,icon});

            db.setTransactionSuccessful();
        } finally {
            db.endTransaction();
        }
    }

    //添加支出3类型
    public void addOutlayCategory(String category,int icon) {
        db.beginTransaction();  //开始事务
        try {
            db.execSQL("INSERT INTO AccountOutlayType(id,category,icon) VALUES(null,?,?)",
                    new Object[]{category,icon});

            db.setTransactionSuccessful();  //设置事务成功完成
        } finally {
            db.endTransaction();    //结束事务
        }
    }
}

完成增删改查等基本操作。

原文地址：https://www.cnblogs.com/dongao/p/12300896.html