Android DatePickerDialog: Set min and max date for selection

Try this method

@NonNull
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    Calendar calendar = Calendar.getInstance();
    int year    = calendar.get(Calendar.YEAR);
    int month   = calendar.get(Calendar.MONTH);
    int day     = calendar.get(Calendar.DAY_OF_MONTH);

    DatePickerDialog dialog = new DatePickerDialog(getContext(), listener, year, month, day);
    Field mDatePickerField;
    try {
            mDatePickerField = dialog.getClass().getDeclaredField("mDatePicker");
            mDatePickerField.setAccessible(true);
    } catch (Exception e) {
            e.printStackTrace();
    }
    dialog.getDatePicker().setMinDate(System.currentTimeMillis() - 1000);
    return dialog;
}

instead of your

@NonNull
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    Calendar calendar = Calendar.getInstance();
    int year    = calendar.get(Calendar.YEAR);
    int month   = calendar.get(Calendar.MONTH);
    int day     = calendar.get(Calendar.DAY_OF_MONTH);

    DatePickerDialog dialog = new DatePickerDialog(getContext(), listener, year, month, day);
    dialog.getDatePicker().setMinDate(calendar.getTimeInMillis());
    return dialog;
}

EDIT1:

I have also faced this issue that user can select not-selectable dates in Android L 5.0.2. Currently there is bug reported here. It is solved in Android L 5.1.0.

For temporary solution of this issue you can compare selected date with current system date and put some condition based on that. I used this as my workaround

EDIT2:

add onDateSent() method in DatePickerDialogFragment and just check if it's earlier than the date you set in setMinDate(). If so, then just show the DatePickerDialog again.

final long today = System.currentTimeMillis() - 1000;

@Override
public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
            Calendar calendar = Calendar.getInstance();
            calendar.set(year, monthOfYear, dayOfMonth);
            //If user tries to select date in past (or today)
            if (calendar.getTimeInMillis() < today)
            {
                //Make them try again
               DatePickerDialogFragment fragment = new DatePickerDialogFragment();
               fragment.setListener(dateSetListener);
               fragment.show(getSupportFragmentManager(), "Choose booking date");
               Toast.makeText(this, "Invalid date, please try again", Toast.LENGTH_LONG).show();
            }
            else
            {
                //success
            }
}

Get System Time and subtract 1 second from It

 @Override
 public Dialog onCreateDialog(Bundle savedInstanceState) {
    Calendar calendar = Calendar.getInstance();
    int year    = calendar.get(Calendar.YEAR);
    int month   = calendar.get(Calendar.MONTH);
    int day     = calendar.get(Calendar.DAY_OF_MONTH);

     dialog = new DatePickerDialog(act, listener, year, month, day);
     dialog.getDatePicker().setMinDate(System.currentTimeMillis() -1000);
     return dialog;
 }

dialog.getDatePicker().setMinDate(calendar.getTimeInMillis());