【Android】家庭记账本手机版开发报告一

一、说在前面

昨天	学习了数据库的一些简单操作
今天	使用数据库，完成对记账本的账单记录的增删
问题	没有

二、数据库

1、账单表的结构

（注 id：账单的唯一标识，uid：记录账单的用户的id，cost_time：记录账单的时间，cost_type：账单类型，cost_money：账单金额。）

2、Entity：AccountRecord.java

package com.me.familybookkeepingbook;

import androidx.room.ColumnInfo;
import androidx.room.Entity;
import androidx.room.PrimaryKey;

@Entity
public class AccountRecord {
    @PrimaryKey(autoGenerate = true)
    private int id;
    @ColumnInfo(name = "uid")
    private int uid;
    @ColumnInfo(name = "cost_time")
    private String costTime;
    @ColumnInfo(name = "cost_type")
    private String costType;
    @ColumnInfo(name = "cost_money")
    private Double costMoney;

    public AccountRecord(int uid, String costTime, String costType, Double costMoney) {
        this.uid = uid;
        this.costTime = costTime;
        this.costType = costType;
        this.costMoney = costMoney;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public int getUid() {
        return uid;
    }

    public void setUid(int uid) {
        this.uid = uid;
    }

    public String getCostTime() {
        return costTime;
    }

    public void setCostTime(String costTime) {
        this.costTime = costTime;
    }

    public String getCostType() {
        return costType;
    }

    public void setCostType(String costType) {
        this.costType = costType;
    }

    public Double getCostMoney() {
        return costMoney;
    }

    public void setCostMoney(Double costMoney) {
        this.costMoney = costMoney;
    }
}

3、对数据库的操作：AccountRecordDao.java

package com.me.familybookkeepingbook;

import androidx.room.Dao;
import androidx.room.Delete;
import androidx.room.Insert;
import androidx.room.Query;
import androidx.room.Update;

import java.util.List;

@Dao
public interface AccountRecordDao {
    @Insert
    void insertAccountRecord (AccountRecord ... AccountRecords);
    @Update
    void updateAccountRecord (AccountRecord ... AccountRecords);
    @Delete
    void deleteAccountRecord (AccountRecord ... AccountRecords);
    @Query("DELETE From ACCOUNTRECORD")
    void deleteAllAccountRecord ();
    @Query("SELECT * From ACCOUNTRECORD ORDER BY ID DESC")
    List<AccountRecord> getAllAccountRecord ();
}

AccountRecordDatabase.java

package com.me.familybookkeepingbook;

import androidx.room.Database;
import androidx.room.RoomDatabase;
@Database(entities = {AccountRecord.class },version = 1,exportSchema = false)
public abstract class AccountRecordDatabase extends RoomDatabase {
    public abstract AccountRecordDao getAccountRecordDao();
}

三、界面布局

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <androidx.constraintlayout.widget.Guideline
        android:id="@+id/guideline"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        app:layout_constraintGuide_percent="0.8" />

    <ScrollView
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_marginStart="1dp"
        android:layout_marginLeft="1dp"
        android:layout_marginEnd="1dp"
        android:layout_marginRight="1dp"
        app:layout_constraintBottom_toTopOf="@+id/guideline"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <TextView
            android:id="@+id/textView"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="@string/textview"
            android:textSize="24sp" />
    </ScrollView>

    <Button
        android:id="@+id/buttonInsert"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/buttonInsert"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toStartOf="@+id/buttonDelete"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="@+id/guideline" />

    <Button
        android:id="@+id/buttonDelete"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/buttonDalete"
        app:layout_constraintBottom_toBottomOf="@+id/buttonInsert"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toEndOf="@+id/buttonInsert"
        app:layout_constraintTop_toTopOf="@+id/buttonInsert" />
</androidx.constraintlayout.widget.ConstraintLayout>

四、界面和数据的绑定

1、界面的更新

void updateView(){
        List<AccountRecord> list = accountRecordDao.getAllAccountRecord();
        String text = "";
        for (int i=0;i<list.size();i++){
            AccountRecord accountRecord = list.get(i);
            text += accountRecord.getId() + "   " + accountRecord.getCostType() + "   "+accountRecord.getCostTime() +"   "+
                    accountRecord.getCostMoney() +"\n";
        }
        textView.setText(text);
    }

2、按键的监听

 buttonInsert.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                AccountRecord accountRecord = new AccountRecord(1,"2020-01-26","学习",100.0);
                accountRecordDao.insertAccountRecord(accountRecord);
                updateView();
            }
        });
        buttonDelete.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                accountRecordDao.deleteAllAccountRecord();
                updateView();
            }
        });

五、运行测试

1、插入：

2、删除