Question

更新

我正在创建怀孕到期日倒计时，因此我使用android.widget.DatePicker作为设置截止日期的工具。

例如：

设置截止日期为Jan. 9 2015
现在的日期是Nov. 9 2014
所以左边的几个月，几天和几周是2 months, 62 days and 8weeks

到目前为止，我只能显示设定截止日期。

问题： 如何在用户设置截止日期时获得确切的几个星期和几天。

更新代码

以下是代码：

private TextView txtResultDueDate ;
       private DatePicker datePicker;
       private Calendar calendar;
       private int year;
       private int month;
       private int day;

       static final int DATE_DIALOG_ID = 999;

       @Override
       protected void onCreate(Bundle savedInstanceState) {

          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_profile);

           txtResultDueDate = (TextView) findViewById(R.id.txtDue);
           btnChangeDate = (Button)findViewById(R.id.button1);

            calendar = Calendar.getInstance();
            year = calendar.get(Calendar.YEAR);
            month = calendar.get(Calendar.MONTH);
            day = calendar.get(Calendar.DAY_OF_MONTH);
            showDate(year, month+1, day);

       @SuppressWarnings("deprecation")
       public void setDate(View view) {
          showDialog(999);
          Toast.makeText(getApplicationContext(), "ca", Toast.LENGTH_SHORT)
          .show();
       }

       @Override
       protected Dialog onCreateDialog(int id) {
       // TODO Auto-generated method stub
          if (id == 999) {
             return new DatePickerDialog(this, myDateListener, year, month, day);
           }
          return null;
       }

       private DatePickerDialog.OnDateSetListener myDateListener
       = new DatePickerDialog.OnDateSetListener() {

       @Override
       public void onDateSet(DatePicker arg0, int year, int month, int day) {
     Chronology chrono = GregorianChronology.getInstance();  
       DateTime end = new DateTime(arg0.getYear(), arg0.getMonth(), arg0.getDayOfMonth(), 0, 0, chrono);

       DateTime current = new DateTime();
       Interval interval = new Interval(current.toInstant(), end.toInstant());
       Period duePeriod = interval.toPeriod();
       showDate(duePeriod.getYears(), duePeriod.getMonths(), duePeriod.getDays());


       }
       };

       private void showDate(int year, int month, int day) {
          txtResultDueDate.setText(new StringBuilder().append(day).append("/")
          .append(month).append("/").append(year));
       }

这是我使用DatePicker设置截止日期时遇到的错误：

致命的例外：主要

java.lang.IllegalArgumentException：结束时刻必须大于等于开头

at org.joda.time.base.Abstraction.checkInterval（AbstractInterval.java.63）

at org.joda.time.base.BaseInterval（BaseInterval.java:94）

at org.joda.time.Interval。（Interval.java.122）

at com.date.androin.Profile $ 1.onDataset（Profile.java:168）

在android.app.DatePickerDialog.tryNotifyDataSet（DatePickerDialog.java.148）

在android.app.DatePickerDialog.onClick（DatePickerDialog.java.116）

at com.android.internal.app.AlertController $ ButtonHandler.handleMessage（AlertController.java:166）

在android.os.Handler.dispatchMessage（Handler.java:99）

在android.os.Looper.loop（Looper.java:137）

在android.app.ActivityThread.main（ActivityThread.java:5103）

at java.lang.reflect.Method.invokeNative（Native Method）

at java.lang.reflect.Method.invoke（Method.java:511）

at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:786）

at com.android.internal.os.ZygoteInit.main（ZygoteInit.java:553）

at dalvik.system.NativeStrat.main（Native Method）

Answer 1

有一个图书馆Joda Time。 Java提供的Date API更好

Joda Time有一个时间间隔的概念：

Interval interval = new Interval(oldTime, new Instant());

是的，您可以将joda lib与android DatePicker

一起使用

Chronology chrono = GregorianChronology.getInstance();
// end datetime
DateTime end = new DateTime(datePicker.getYear(), datePicker.getMonth(),       datePicker.getDayOfMonth(), 0, 0 ,chrono);

// current datetime
DateTime current = new DateTime();

然后使用开始和结束日期时间实例化Interval

Interval interval = new Interval(current.toInstant(), end.toInstant()); 然后使用Interval api获取可以提取月/天/周差异的时间段

Period duePeriod = interval.toPeriod();

// get difference in months

duePeriod.getMonths();

// get difference in weeks

duePeriod.getWeeks();

请参阅以下Javadoc of Period以获取API的完整列表 http://joda-time.sourceforge.net/apidocs/org/joda/time/Period.html

对于Android，在您的情况下，将上述代码添加到DatePicker onDateSet侦听器中。最后，监听器方法会这样，

@Override
public void onDateSet(DatePicker arg0, int year, int month, int day) {
   // TODO Auto-generated method stub
   Chronology chrono = GregorianChronology.getInstance(); 
   // end datetime 
   DateTime end = new DateTime(arg0.getYear(), arg0.getMonth(), arg0.getDayOfMonth(), 0, 0, chrono);
   // current datetime 
   DateTime current = new DateTime();
   Interval interval = new Interval(current.toInstant(), end.toInstant());
   Period duePeriod = interval.toPeriod();
   showDate(duePeriod.getYears(), duePeriod.getMonths(), duePeriod.getDays());
}

Answer 2

//somewhere in your code, init part
Calendar then = setDate(9, 0, 2015);//9 january 2015
Calendar c = Calendar.getInstance();
Calendar now = setDate(c.get(Calendar.DAY_OF_MONTH), c.get(Calendar.MONTH), c.get(Calendar.YEAR));
String leftDays = getLeftDays(then, now);//your result

//method setting days months years - we ignore hours and minutes
private String getLeftDays(Calendar then, Calendar now) {
    long leftMilis = then.getTimeInMillis() - now.getTimeInMillis();
    int seconds = (int) (leftMilis / 1000);
    Log.d(TAG, "seconds:" + seconds);
    int minutes = seconds / 60;
    Log.d(TAG, "minutes:" + minutes);
    int hours = minutes / 60;
    Log.d(TAG, "hours:" + hours);
    int days = hours / 24;
    Log.d(TAG, "days:" + days);
    int weeks = days / 7;
    Log.d(TAG, "weeks:" + weeks);

    //months.. another way calculating data due not equal amount of days per month
    Calendar temp = ((Calendar) then.clone());
    temp.add(Calendar.MONTH, -now.get(Calendar.MONTH));
    int months = temp.get(Calendar.MONTH);
    Log.d(TAG, "months:" + months);

    StringBuilder sb = new StringBuilder();
    String format = "%d months, %d days, %d weeks";
    String formatStr = String.format(format, months, days, weeks);

    String result = sb.append(formatStr).toString();
    Log.d(TAG, sb.toString());
    return result;
}

private Calendar setDate(int day, int month, int year) {
    Calendar c = Calendar.getInstance();
    c.set(Calendar.DAY_OF_MONTH, day);
    c.set(Calendar.MONTH, month);
    c.set(Calendar.YEAR, year);
    c.set(Calendar.HOUR, 0);
    c.set(Calendar.MINUTE, 0);
    c.set(Calendar.SECOND, 0);
    Log.d(TAG, c.getTime().toString());
    return c;
}

Answer 3

日历c = calendar.getInstance（）;

和DatePickerDialog d

@覆盖 public void onDateSet（DatePicker视图，int Year，int mont of Year，int day of month）{

吐司

c.get（Calendar.Year），c.get（的Calendar.MONTH），c.get（Calendar.Day_of_Month）;

d.show

Answer 4

this code is to find week from selected date,it's proper work.
Calendar date1 = Calendar.getInstance();
        Calendar date2 = Calendar.getInstance();

        date1.clear();
        date1.set(Integer.parseInt(selected_year), Integer.parseInt(selected_month), Integer.parseInt(selected_date)); // set date 1 (yyyy,mm,dd)
        System.out.println("Selected Date==>>" + date1);

        date2.clear();
        date2.set(Integer.parseInt(current_year), Integer.parseInt(current_month), Integer.parseInt(current_date));
        System.out.println("Current Date==>>" + date2);

        long diff = date2.getTimeInMillis() - date1.getTimeInMillis();
        float dayCount = (float) diff / (24 * 60 * 60 * 1000);
        week = (int) (dayCount / 7);

        if (week <= 0) {
            Toast.makeText(this, "Sry System Error", Toast.LENGTH_SHORT).show();
            System.out.println("Week==>>" + week);
            test = false;
        } else {
            Toast.makeText(this, "Done", Toast.LENGTH_SHORT).show();
            System.out.println("Week==>>" + week);
            test = true;
        }

如何获得MONTHS，DAYS和周（android datepicker）

4 个答案: