title: enterText() in Robotium
body: <p>i am new in android testing, I try to calculate two values using Edit Text. i tried in two ways. One way is solo.enterText(EditText edittext, String text); and another one is solo,enterText(int index, String text);</p>
  
  <p>This one is working for me</p>
  
  <pre><code>//Access First value (editfiled) and putting firstNumber value in it
  EditText FirsteditText = (EditText) solo.getView(R.id.EditText01);
  solo.enterText(FirsteditText, String.valueOf("10"));
  </code></pre>
  
  <p>This one is not working for me</p>
  
  <pre><code>solo.enterText(0, "10");
  </code></pre>
  
  <p>whats the problem here?</p>