Question

我正在尝试设置日历对象 - ＆gt;今天到一个月的第一周的特定日子。

    Calendar today = Calendar.getInstance();

    today.set(Calendar.HOUR_OF_DAY, 0); // ! clear would not reset the hour of day !
    today.clear(Calendar.MINUTE);
    today.clear(Calendar.SECOND);
    today.clear(Calendar.MILLISECOND);
    today.getTime();

    today.set(Calendar.YEAR,year);
    today.set(Calendar.MONTH, month);
    today.set(Calendar.WEEK_OF_MONTH,today.getActualMinimum(Calendar.WEEK_OF_MONTH));
    today.set(Calendar.DAY_OF_WEEK, getDay()+1);

    Log.d(TAG, "Test : "+getName()+", time : "+ today.getTime()+"  ,year : "+year+"   ,month : "+ month);

问题是，日历正在返回当前日期的当天日期。

Answer 1

使用以下代码：

public static String getEightWeeksDateString() {
    DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-01 00:00:00");
    Calendar cal = Calendar.getInstance();
    cal.add(Calendar.DATE, 0);
    return dateFormat.format(cal.getTime());
}

以字符串格式返回日期，然后你应该把它转换成你想要的

Answer 2

 Calendar c = Calendar.getInstance();   // this takes current date
    c.set(Calendar.DAY_OF_MONTH, 1);

Answer 3

班级日历中有一个DAY_OF_MONTH字段，如果您想要完成目标，则需要更改该字段。查看documentation。你只需要使用set方法：

today.set(Calendar.DAY_OF_MONTH, 1);

Answer 4

您可以使用以下代码。它会将当天的日期返回到当天的第一周。

public String getDayFromFirstWeek() {
    DateFormat formatter = new SimpleDateFormat("dd/MM/yyyy",Locale.getDefault());

    Calendar date = Calendar.getInstance(Locale.getDefault());
    date.set(Calendar.DAY_OF_MONTH, 1);
    date.add(Calendar.DAY_OF_YEAR, (date.get(Calendar.DAY_OF_WEEK)+ Calendar.getInstance().get(Calendar.DAY_OF_WEEK) - 1) % 7);
    return formatter.format(date.getTime());
}

Answer 5

以下代码有助于在特定月份内创建重复事件。

   Calendar today = Calendar.getInstance();

    today.clear();
    today.set(Calendar.DAY_OF_MONTH, 1);
    today.set(Calendar.YEAR,year);
    today.set(Calendar.MONTH, month-1);
    today.set(Calendar.DAY_OF_MONTH, 1);
    today.add(Calendar.DAY_OF_YEAR,0); 
    today.getTime();

    long id = (getId()*10000)+(year%100)*100;


    for(int i = 0; i<today.getActualMaximum(Calendar.WEEK_OF_MONTH);i++){

        Calendar startTime = (Calendar) today.clone();
        Calendar endTime = (Calendar) today.clone();

        startTime.setTimeInMillis(start.getTime());
        startTime.set(Calendar.YEAR, year);
        startTime.set(Calendar.MONTH,month-1);
        startTime.add(Calendar.DAY_OF_YEAR,7*i); 
        startTime.set(Calendar.DAY_OF_WEEK,getDay()+1);
        startTime.getTime();

        if(startTime.get(Calendar.MONTH) == month) //break the loop if enters next month.
            break;

        endTime.setTimeInMillis(end.getTime());
        endTime.set(Calendar.YEAR, year);
        endTime.set(Calendar.MONTH,month-1);
        endTime.add(Calendar.DAY_OF_YEAR,7*i); 
        endTime.set(Calendar.DAY_OF_WEEK,getDay()+1);
        endTime.getTime();


        // Set values into event.
        WeekViewEvent weekViewEvent = new WeekViewEvent();
        weekViewEvent.setName(getName());
        weekViewEvent.setId(id+startTime.get(Calendar.WEEK_OF_YEAR));
        weekViewEvent.setStartTime(startTime);
        weekViewEvent.setEndTime(endTime);
        weekViewEvent.setColor(Color.GREEN);
        weekViewEvent.setEventBy(getEventBy());

        Log.d(TAG, "weekly event recieved : "+getName()+",  id : "+weekViewEvent.getId()+", time : "+ startTime.getTime() +" - "+ endTime.getTime());
        // Append WeekViewEvent to the list.
        list.add(weekViewEvent);


    }

在Java中将日历设置为一个月的第一周

5 个答案: