AccountApp

AccountApp

[TOC]

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RecordBean数据抽象类

UUID

uuid = UUID.randomUUID().toString();

输出：

RecordBean: 772c4b12-9439-4217-93da-37613ad78be4
RecordBean: b0351438-21de-4bea-91c1-622f3db9052b

时间戳：

timeStamp = System.currentTimeMillis();

输出(long型的时间戳)：

RecordBean: 1556431010425

日期操作类：

转换时间戳的静态方法：

//导包：
//import java.text.SimpleDateFormat;
//import java.util.Date;
//util time -> HH:mm
public static String getFormattedTime(long timeStamp){
    SimpleDateFormat formatter = new SimpleDateFormat("HH:mm");
    return formatter.format(new Date(timeStamp));

}

得到今天日期的静态方法：

//得到今天日期
//util time(今天日期) -> yyyy-MM-dd
public static String getFormattedDate(){
    SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
    return formatter.format(new Date());
}

输出：

2019-04-28

android上转换后的时间少了8小时，时间戳后面多了三位（前面几位正确的），用命令行Java转换也能得到正确的时间

网上有人说：

“这个时间时慕课服务器上的，它服务器采用的时utc时间，而我们电脑本地的时间时东八区，也就是utc+8的时间。当然差了8个小时啦。

换言之，如果慕课他们服务器上的时间一直采用UTC，我们就比他们快8小时。”

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.我暂时不处理.

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• .RecordDatabaseHelper.

数据库实现：

SQLiteOpenHelper类

两个回调必须重写：

• onCreate
• onUpgrade

编写自己的数据库操作帮组类，并继承SQLiteOpenHelper：

public class RecordDatabaseHelper extends SQLiteOpenHelper 

onCreate回调时自动创建一张表：

public void onCreate(SQLiteDatabase db) {
    db.execSQL(CREATE_RECORD_DB);   //执行SQL语句的方法：exeSQL(String)    //表纯在不执行
}

​ 其中的SQL语句：

• public static final String CREATE_RECORD_DB = "create table Record("
  + "id integer primary key autoincrement,"
  + "uuid text,"
  + "type integer,"
  + "remark integer,"
  + "time integer,"
  + "amount double,"
  + "data data)";
  

这个主要用来对要操作的数据库进行操作（增删改查）的：

//插入一条记录
public void addRecord(RecordBean bean){
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put("uuid",bean.getUuid());
    values.put("type",bean.getType());
    values.put("remark",bean.getRemark());
    values.put("amount",bean.getAmount());
    values.put("date",bean.getDate());
    values.put("time",bean.getTimeStamp());
    db.insert(DB_NAME,null,values);
}
//删除一条记录  //根据uuid删除
public void removeRecord(String uuid){
    SQLiteDatabase db = this.getWritableDatabase();
    db.delete(DB_NAME,"uuid = ?",new String[]{uuid});
}
//编辑记录  //根据uuid编辑
public void editRecord(String uuid,RecordBean bean){
    //先删除旧记录
    removeRecord(uuid);
    //在添加新记录
    addRecord(bean);
}

//查询
public LinkedList readRecords(String dateStr){
    LinkedList records = new LinkedList<>();
    SQLiteDatabase db = this.getWritableDatabase();

    Cursor cursor = db.rawQuery("select DISTINCE * from Record where data = ? order by time asc",new String[]{dateStr});
    if(cursor.moveToFirst()){
        do {
            //字段
            String uuid = cursor.getString(cursor.getColumnIndex("uuid"));
            int type = cursor.getInt(cursor.getColumnIndex("type"));
            String category = cursor.getString(cursor.getColumnIndex("category"));
            String remark = cursor.getString(cursor.getColumnIndex("remark"));
            double amount = cursor.getDouble(cursor.getColumnIndex("amount"));
            String date = cursor.getString(cursor.getColumnIndex("date"));
            long timeStamp = cursor.getLong(cursor.getColumnIndex("time"));

            RecordBean record = new RecordBean();
            record.setUuid(uuid);
            record.setType(type);
            record.setCategory(category);
            record.setRemark(remark);
            record.setAmount(amount);
            record.setDate(date);
            record.setTimeStamp(timeStamp);

            records.add(record);
        }while (cursor.moveToNext());
    }
    cursor.close();

    return records;
}
//
public LinkedList getAvaliableDate(){
    LinkedList dates = new LinkedList<>();
    SQLiteDatabase db = this.getWritableDatabase();

    Cursor cursor = db.rawQuery("select DISTINCE * from Record order by date asc",new String[]{});
    if(cursor.moveToFirst()){
        do {
            String data = cursor.getString(cursor.getColumnIndex("date"));
            if (!dates.contains(data)){
                dates.add(data);
            }
        }while (cursor.moveToNext());
    }
    cursor.close();

    return dates;
}

查询的操作还可以学习下

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.界面布局.

数字滚动动画使用第三方开源库：

Robinhood

安装：

implementation 'com.robinhood.ticker:ticker:2.0.1'

使用：

final TickerView tickerView = findViewById(R.id.tickerView);
tickerView.setCharacterLists(TickerUtils.provideNumberList());

添加依赖：

support-v13 --> (CoordinatorLayout(协调布局)

support:design --> FloatButton

添加之后会在bulid:gradle（module:app）添加：

implementation 'com.android.support:support-v13:28.0.0'
implementation 'com.android.support:design:28.0.0'

CoordinatorLayout

android:fitsSystemWindows="true"

AppBarLayout:

android:elevation="0dp"   

设置高度