title: What's the need to call DataBindingUtil.setContentView() when using Data Binding Library?
body: <p>I am learning to use Data Binding Library. I came to know that it removes the need to call findViewById() manually and makes the code more robust and readable.</p>
  
  <p>To understand the use, I did the following:</p>
  
  <ol>
  <li><p>made a temp_layout.xml which contains 2 text views with ids 'tv1' and 'tv2'</p></li>
  <li><p>added the <code>&lt;layout&gt;</code> tag as root</p></li>
  <li><p>clicked on 'build project'</p></li>
  </ol>
  
  <p>Now I found that a new 'TempLayoutBinding' class was available which contained the variables 'tv1' and 'tv2'.</p>
  
  <p><strong>My question is that</strong>, even when I already specified the <code>&lt;layout&gt;</code> tag in the temp_layout.xml, why do I still need to call <code>mBinding = DataBindingUtil.setContentView(...)</code>?
  What specifically does it do?</p>