Android/Java - Date Difference in days

Question

I am getting the current date (in format 12/31/1999 i.e. mm/dd/yyyy) as using the below code:

Textview txtViewData;
txtViewDate.setText(\"Today is \" +
              


        

Answer 1

Not really a reliable method, better of using JodaTime

  Calendar thatDay = Calendar.getInstance();
  thatDay.set(Calendar.DAY_OF_MONTH,25);
  thatDay.set(Calendar.MONTH,7); // 0-11 so 1 less
  thatDay.set(Calendar.YEAR, 1985);

  Calendar today = Calendar.getInstance();

  long diff = today.getTimeInMillis() - thatDay.getTimeInMillis(); //result in millis

Here's an approximation...

long days = diff / (24 * 60 * 60 * 1000);

To Parse the date from a string, you could use

  String strThatDay = "1985/08/25";
  SimpleDateFormat formatter = new SimpleDateFormat("yyyy/MM/dd");
  Date d = null;
  try {
   d = formatter.parse(strThatDay);//catch exception
  } catch (ParseException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  } 


  Calendar thatDay = Calendar.getInstance();
  thatDay.setTime(d); //rest is the same....

Although, since you're sure of the date format... You Could also do Integer.parseInt() on it's Substrings to obtain their numeric values.