title: How to calculate EditText value in Android?
body: <p>In an Android app, I'm using two <code>EditText</code> controls and multiplying their two values.
  If one <code>EditText</code> is <code>null</code> and in the second one I put a value, it's not working properly.
  How can I deal with this case, in which I have a value in one <code>EditText</code> and a <code>null</code> in the other and I want to multiply the two values?</p>