title: Hide android.support.v7.widget.Toolbar programmatically
body: <p>In my activity I do:</p>
  
  <pre><code>setSupportActionBar(toolbar);
  </code></pre>
  
  <p>where toolbar is an instance of android.support.v7.widget.Toolbar</p>
  
  <p>Is there any way after this to hide and show back Toolbar widget programmatically? I already tried</p>
  
  <pre><code>toolbar.setVisibility(View.INVISIBLE);
  </code></pre>
  
  <p>but this only makes it invisible and it still takes space, so that content of the activity starts after it, and I see white space instead in the header.</p>