title: On screen orientation change of my android app layout
body: <p>When orientation of screen changes, I have read many a times that in order to save data of edit text and text view or any of the radio button I have to use <code>onSaveInstanceState()</code> method.</p>
  
  <p>But when I'm changing the screen orientation my data of edit text, text view and radio button are not getting erased.</p>
  
  <p>So what is the main purpose of using <code>onSaveInstanceState()</code> method. Why do we have to use it if my data are preserved safely ?</p>