title: How to get int to a SimpleDateFormat
body: <p>I have a method that collect the year, month and day from a DatePicker and stores them in separate integers.</p>
  
  <pre><code>public void onDateChanged(DatePicker datePicker, int year, int month, int dayOfMonth) {                    
      yearD = year;
      monthD = (month + 1);
      dayD = dayOfMonth;
  }
  </code></pre>
  
  <p>How can I transform these integers to a SimpleDateFormat with the pattern "yyyy-MM-dd"?</p>
  
  <pre><code>SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
  </code></pre>