How to add days into the date in android

Question

In my database I am getting start date like 2011-11-30(yyyy/mm/dd)format.and duration date like 40 days.How can i calculate the days and get new date format of mm/dd/yyyy.

Answer 1

It works for me.

Calendar c = Calendar.getInstance();
int mYear = c.get(Calendar.YEAR);
int mMonth = c.get(Calendar.MONTH);
int mDay = c.get(Calendar.DAY_OF_MONTH);

String CurrentDate = mYear + "/" + mMonth + "/" + mDay;
String dateInString = dob; // Select date
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
c = Calendar.getInstance();
try {
c.setTime(sdf.parse(dateInString));
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
c.add(Calendar.DATE, 14);    //14 dats add
sdf = new SimpleDateFormat("dd/MM/yyyy");
Date resultdate = new Date(c.getTimeInMillis());
dateInString = sdf.format(resultdate);
System.out.println(dateInString);

Answer 2

Calendar c = Calendar.getInstance();
    int mYear = c.get(Calendar.YEAR);
    int mMonth = c.get(Calendar.MONTH);
    int mDay = c.get(Calendar.DAY_OF_MONTH);

    // display the current date
    String CurrentDate = mYear + "/" + mMonth + "/" + mDay;

    String dateInString = CurrentDate; // Start date
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

    c = Calendar.getInstance();

    try {
        c.setTime(sdf.parse(dateInString));
    } catch (ParseException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    c.add(Calendar.DATE, 7656);//insert the number of days you want to be added to the current date
    sdf = new SimpleDateFormat("dd/MM/yyyy");
    Date resultdate = new Date(c.getTimeInMillis());
    dateInString = sdf.format(resultdate);

    //Display the Result in the Edit Text or Text View your Choice
    EditText etDOR = (EditText)findViewById(R.id.etDateOfReturn);
    etDOR.setText(dateInString);

Answer 3

You can try something like this,

String dt = "2012-01-04";  // Start date
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Calendar c = Calendar.getInstance();
try {
    c.setTime(sdf.parse(dt));
} catch (ParseException e) {
    e.printStackTrace();
}
c.add(Calendar.DATE, 40);  // number of days to add, can also use Calendar.DAY_OF_MONTH in place of Calendar.DATE
SimpleDateFormat sdf1 = new SimpleDateFormat("MM-dd-yyyy");
String output = sdf1.format(c.getTime()); 

Answer 4

Step-1 Get Calendar instance from the specified string

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
            Calendar c = Calendar.getInstance();
            c.setTime(sdf.parse(dateInString));

Step-2 use add() to add number of days to calendar

c.add(Calendar.DATE, 40); 

Step-3 Convert the dtae to the resultant date format

sdf = new SimpleDateFormat("MM/dd/yyyy");
            Date resultdate = new Date(c.getTimeInMillis());
            dateInString = sdf.format(resultdate);

Source Code

String dateInString = "2011-11-30";  // Start date
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Calendar c = Calendar.getInstance();
        c.setTime(sdf.parse(dateInString));
        c.add(Calendar.DATE, 40);  
        sdf = new SimpleDateFormat("MM/dd/yyyy");
        Date resultdate = new Date(c.getTimeInMillis());
        dateInString = sdf.format(resultdate);
        System.out.println("String date:"+dateInString);

Answer 5

Don't use:

Calendar c = Calendar.getInstance();

Use this instead:

GregorianCalendar calendar =new GregorianCalendar();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.add(Calendar.DAY_OF_MONTH , 30);

Answer 6

This piece of code should do the job well!!!

public static String addDay(String oldDate, int numberOfDays) {
    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
    Calendar c = Calendar.getInstance();
    try {
        c.setTime(dateFormat.parse(oldDate));
    } catch (ParseException e) {
        e.printStackTrace();
    }
    c.add(Calendar.DAY_OF_YEAR,numberOfDays);
    dateFormat=new SimpleDateFormat("MM-dd-YYYY");
    Date newDate=new Date(c.getTimeInMillis());
    String resultDate=dateFormat.format(newDate);
    return resultDate;
}

For more functionality do please checkout this link
Add days,months,years to a date