title: how to get the sum of selected checkboxes in android?
body: <p>I'am newer. I get a problem at java.</p>
  
  <p>in XML, If I have 2 checkboxes,
  O book
  O pencil
  Total is : . . .</p>
  
  <p>I want to sum of selected checkboxes.
  If book=10 and pencil=5.
  How?</p>