title: Qt: UI with c++ vs with xml vs with qml
body: <p>I have started learning qt today and have a question. When I create a project, it comes with *.ui file which is XML kind of file but in the book, I am only creating UI with pure c++(classes). I have heard there is another way of creating the UI with qml.</p>
  
  <p>So, What are pros and cons of each UI creating way?</p>
  
  <p>Thanks in advance</p>
  
  <p>EDIT: I am using QT 5.1.0</p>