datePicker.getMonth() +1 doesn't give expected result

Question

             Toast.makeText(getBaseContext(),
            "Date selected:" + datePicker.getMonth()+1+
            "/"+ datePicker.getDayOfMonth() +
            "/"+ datePicker.getYear() +"\n" +
            "Time Slected:" + timePicker.getCurrentHour() + 
            ":"+ timePicker.getCurrentMinute(),
            Toast.LENGTH_SHORT).show();

BY adding 1 to the datePicker.getMonth(),i am getting month number

            output like->
            jan-01,feb-11,mar-21

But when i removing the "1" i am getting month number output like

            jan-0,feb-01,mar-02

Answer 1

You want parentheses.

(datePicker.getMonth()+1)

Otherwise you are doing string concatenation.

For example

If getMonth() returns 0 (for January), then

"Date selected: " + datePicker.getMonth()+1

is

("Date selected: " + 0) + 1
= "Date selected: 0" + 1
= "Date selected: 01"

But with parens

"Date selected: " + (datePicker.getMonth()+1)
= "Date selected: " + (0+1)
= "Date selected: " + 1
= "Date selected: 1"