Question

我目前正在尝试在用户可以输入日期的功能中加入一个功能，然后当他们保存日期时，我想计算从今天开始到该日期的剩余天数。我的代码如下：

public void daysLeft(String dateSent){

    String []ar = dateSent.split("[/]");
    int mDay = Integer.parseInt(ar[1]);
    int mMonth = Integer.parseInt(ar[0]);
    int mYear = Integer.parseInt(ar[2]);

    Time TimerSet = new Time();
    TimerSet.set(0, 5, 0, mDay, mMonth, mYear); //day month year
    TimerSet.normalize(true);
    long millis = TimerSet.toMillis(true);

    Time TimeNow = new Time();
    TimeNow.setToNow(); // set the date to Current Time
    TimeNow.normalize(true);
    long millis2 = TimeNow.toMillis(true);

    long millisset = millis - millis2; //subtract current from future to set the time remaining

    final int smillis = (int) (millis); //convert long to integer to display conversion results
    final int smillis2 = (int) (millis2);

    new CountDownTimer(millisset, 1000) {
        public void onTick(long millisUntilFinished) {

            mText = (TextView)findViewById(R.id.DateData);

            // decompose difference into days, hours, minutes and seconds 
            int weeks = (int) ((millisUntilFinished / 1000) / 604800);
            int days = (int) ((millisUntilFinished / 1000) / 86400);
            int hours = (int) (((millisUntilFinished / 1000) - (days * 86400)) / 3600);
            int minutes = (int) (((millisUntilFinished / 1000) 
                            - ((days * 86400) + (hours * 3600))) / 60);
            int seconds = (int) ((millisUntilFinished / 1000) % 60);
            int millicn = (int) (millisUntilFinished / 1000);

            mText.setText(" " + days);
            saveDate(String.valueOf(days));
        }

        public void onFinish() {}
    }.start();
}

当我运行此代码并说日期为2015年7月19日，然后剩下的日子回到760，他们本应该是730.我认为有一些计算略有偏离，真的很感激一些帮助有这个。

由于

Answer 1

错误在月计算中。在java中，Months从0开始（0表示1月）。

因此，

int mMonth = Integer.parseInt(ar[0]);

在您的示例中不正确，它被解释为8月。

您需要减去1：

int mMonth = Integer.parseInt(ar[0]) - 1;

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TimerSet.set(0, 5, 0, mDay, mMonth, mYear);

需要一个基于0的月份。 7，在您的示例中，被理解为August，这就是您需要将1减去您解析的基于1的值的原因。

Answer 2

您可以使用我的TimeSpan课程：

Calendar future = Calendar.getInstance();
future.set(2015, 6, 19); // month is zero based

Date now = Calendar.getInstance().getTime();

TimeSpan timeSpan = TimeSpan.fromMiliseconds(future.getTimeInMillis() - now.getTime());

Log.d(TAG, "Days left : " + timeSpan.getDays()); // "Days left : 730"

TimeSpan上课：

public class TimeSpan implements Comparable<TimeSpan> {
    Long days;
    Long hours;
    Long minutes;
    Long seconds;
    Long milliseconds;

    public TimeSpan() {
        days = hours = minutes = seconds = milliseconds = 0l;
    }

    public TimeSpan(long _days, long _hours, long _minutes, long _seconds, long _milliseconds) {

        long totalMS = _days * 86400000 + _hours * 3600000 + _minutes * 60000 + _seconds * 1000 + _milliseconds;

        days = Long.valueOf(totalMS / 86400000);
        totalMS -= days * 86400000;

        hours = Long.valueOf((int) totalMS / 3600000);
        totalMS -= hours * 3600000;

        minutes = Long.valueOf((int) totalMS / 60000);
        totalMS -= minutes * 60000;

        seconds = Long.valueOf((int) totalMS / 1000);
        totalMS -= seconds * 1000;

        milliseconds = Long.valueOf((int) totalMS);
    }

    public static TimeSpan fromSeconds(int _seconds) {
        return new TimeSpan(0, 0, 0, _seconds, 0);
    }

    public static TimeSpan fromMiliseconds(long _miliseconds) {
        return new TimeSpan(0, 0, 0, 0, _miliseconds);
    }

    @Override
    public String toString() {
        return Long.toString(getTotalMilliseconds());
    }

    public String toSimpleShortString() {
        if (hours > 0)
            return String.format("%d:%d:%02d", hours, minutes, seconds);
        else
            return String.format("%d:%02d", minutes, seconds);
    }

    public String toShortString() {
        return String.format("%02d:%02d:%02d", hours, minutes, seconds);
    }

    public String toLongString() {
        return String.format("%02d:%02d:%02d:%02d", hours, minutes, seconds, milliseconds);
    }

    public long getHours() {
        return hours;
    }

    public long getDays() {
        return days;
    }

    public long getMinutes() {
        return minutes;
    }

    public long getSeconds() {
        return seconds;
    }

    public long getMilliseconds() {
        return milliseconds;
    }

    public long getTotalMilliseconds() {
        return days * 86400000 + hours * 3600000 + minutes * 60000 + seconds * 1000 + milliseconds;
    }

    @Override
    public int compareTo(TimeSpan another) {
        return (int) (getTotalMilliseconds() - another.getTotalMilliseconds());
    }
}

Android天左计算错了？

2 个答案:

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