DatePicker.OnDateChangedListener called twice

Question

I\'m trying to create an app where the user selects a date from a DatePicker, and then a list is updated with some values.

My GUI looks like this:

Answer 1

Instead of the onDateSet callback I've overridden onClick method of the DatePickerDialog dialog and handle BUTTON_POSITIVE clicks only.

public static class DatePickerFragment extends DialogFragment {
    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        final Calendar c = Calendar.getInstance();
        int initialYear = c.get(Calendar.YEAR);
        int initialMonth = c.get(Calendar.MONTH);
        int initialDay = c.get(Calendar.DAY_OF_MONTH);
        return new DatePickerDialog(getActivity(), null, initialYear, initialMonth, initialDay) {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                if (which == BUTTON_POSITIVE) {
                    int year = getDatePicker().getYear();
                    int month = getDatePicker().getMonth();
                    int day = getDatePicker().getDayOfMonth();

                    //TODO: Do your logic here
                }
                super.onClick(dialog, which);
            }
        };
    }
}

The code stays clear but still it's not clear why onDateSet is called twice.

Answer 2

private DatePicker.OnDateChangedListener dateSetListener = new DatePicker.OnDateChangedListener() {
    boolean fired = false;
    public void onDateChanged(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
         if (fired == true){
//Twince
         }
         else{
             Calendar c = Calendar.getInstance();
             c.set(year, monthOfYear, dayOfMonth);
             System.out.println ("TEST");
         }

    }
};

Answer 3

Please check my answer over here. It is for TimePickerDialog but also applicable for DatePickerDialog. You can create a custom dialog, it's almost equally as fast and simple and just works.

https://stackoverflow.com/a/25672760/940450

Answer 4

When I test my application, method onDateSet called twice after accept the date selection and once when I canceled.

I added a validation in the method onDateSet with parameter view, something like this

@Override
public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth){
    if (view.isShown()) {
        updateDate(year, monthOfYear, dayOfMonth);
    }
}

I hope you serve

Answer 5

private DatePicker.OnDateChangedListener dateSetListener = new DatePicker.OnDateChangedListener() { 

    public void onDateChanged(DatePicker view, int year, int monthOfYear, 
            int dayOfMonth) { 
         Calendar c = Calendar.getInstance(); 
         c.set(year, monthOfYear, dayOfMonth); 
         updateDisplay();

    } 
}; 


TextView datetext;
datetext = (TextView) findViewById(R.id.selected_date);


private void updateDisplay() {
        this.datetext.setText(new StringBuilder()
                // Month is 0 based so add 1
                .append(mMonth + 1).append("-").append(mDay).append("-")
                .append(mYear).append(" "));
    }

Answer 6

Perhaps modify the listener by adding instance variables, that way you can check to see if they are different from the last time the method was called:

final DatePickerDialog datePickerDialog = new DatePickerDialog (this, new DatePickerDialog.OnDateSetListener()
    {   
        private int year;
        private int month;
        private int day;

        @Override
        public void onDateSet (DatePicker view, int year, int monthOfYear, int dayOfMonth)
        {
            if (this.year == year && this.month == monthOfYear && this.day == dayOfMonth)
                return;

            this.year = year;
            this.month = monthOfYear;
            this.day = dayOfMonth;

            calendar.set (year, month, day);
            int index = officeCalendar.indexOfKey (calendar.getTimeInMillis ());

            if (index > -1)
                viewPager.setCurrentItem (index);
        }
    }, calendar.get (Calendar.YEAR), calendar.get (Calendar.MONTH), calendar.get (Calendar.DATE));