title: Android Home button in collapsing toolbar with image
body: <p>I am looking to keep the home button in my toolbar. I have a collapsing toolbar with an image which disappears if scrolled up. In my other toolbar I implemented the tool bar with :</p>
  
  <pre><code>getSupportActionBar().setHomeButtonEnabled(true);
  getSupportActionBar().setDisplayHomeAsUpEnabled(true);
  </code></pre>
  
  <p>but it doesn't work now. I can't see the button both when the toolbar is collapsed (when the image isn't shown) and when the toolbar is open (when the image is visible and the toolbar is expanded).</p>
  
  <p>My Toolbar code:</p>
  
  <pre><code>    Toolbar toolbar = (Toolbar) findViewById(R.id.anim_toolbar);
      setSupportActionBar(toolbar);
      getSupportActionBar().setHomeButtonEnabled(true);
      getSupportActionBar().setDisplayHomeAsUpEnabled(true);
      CollapsingToolbarLayout collapsingToolbar = (CollapsingToolbarLayout) findViewById(R.id.collapsing_toolbar);
      collapsingToolbar.setTitle("Awesome");
  </code></pre>