title: Do you have to call setContentView() from onConfigurationChanged()?
body: <p>I've set the manifest entry for my Activity so that it handles orientation changes by itself.</p>
  
  <p>In my <code>onConfigurationChanged()</code>, I've got this:</p>
  
  <pre><code>@Override
  public void onConfigurationChanged(Configuration newConfig) {
      super.onConfigurationChanged(newConfig);
  
      findViewById(R.id.header).post(new Runnable() {
          @Override
          public void run() {
          }
      });
  }
  </code></pre>
  
  <p>After months of working without problems, I've just had a <code>NullPointerException</code> on the <code>findViewById()</code> line. My conclusion is that the <code>View</code> in question hasn't been created yet, due to the omission of <code>setContentView()</code>.</p>
  
  <p>Is <code>setContentView()</code> really necessary here? If so, why has it been working all this time without incident?</p>