title: how to access views in tab activity?
body: <p>I've created an android application to my final project 
  it has a tab activity with three tabs, within each tab there are a lot of components. For example, in the second tab I have a WebView and a button and, when I click the button, the webview must load some data.<br>
  How can I handle the code?<br>
  In the tab1activity.java is not possible because there is no <code>findViewById()</code> also in mainactivity.java that's make my app crashed 
  what can I do?</p>