title: Should we replace Action Bar by ToolBar?
body: <p>I have been using <code>ToolBar</code> since it was added into <strong>Support v7 library</strong>. And I think I used it well. But there is a point I can't understand. Why would Google create such a widget? I mean we can do anything <code>ToolBar</code> can do by using <code>ActionBar</code>. Why do we have to use <code>ToolBar</code>? What are advantages of <code>ToolBar</code> over <code>ActionBar</code> if any? Is it necessary to replace <code>ActionBar</code> by <code>ToolBar</code>?</p>
  
  <p>Any tips are appreciated. And thanks in advance.</p>
  
  <p><strong>PS:</strong> I found <code>ToolBar</code> is a decandant of <code>ViewGroup</code>. So, how could we use <code>ToolBar</code> like a <code>Layout</code>? Could somebody post some codes of that?</p>