title: How to play a local video in a Qt Widgets Application, in Qt creator?
body: <p>This is probably a very noob question... I am very new to Qt, and trying programming in Qt creator. Now I created a new Qt Widgets Application from Qt creator, and want to play a video with it. I now have the following 6 files in my project:</p>
  
  <ul>
  <li>Project
  <ul>
  <li>Project.pro</li>
  <li>Headers
  <ul>
  <li>videoplayer.h</li>
  </ul></li>
  <li>Sources
  <ul>
  <li>main.cpp</li>
  <li>videoplayer.cpp</li>
  </ul></li>
  <li>Forms
  <ul>
  <li>videoplayer.ui</li>
  </ul></li>
  <li>Other files
  <ul>
  <li>/Users/somebody/somewhere
  <ul>
  <li>Demo.mp4</li>
  </ul></li>
  </ul></li>
  </ul></li>
  </ul>
  
  <p>Where and how exactly should I write my code to make it play Demo.mp4 when I run my application (maybe using some tools called QVideoPlayer)? Should I add some Qwidget onto my videoplayer.ui? I now have four buttons "play", "pause", "full_screen" and "rearrange" on my videoplayer.ui. The result I want is something with features of:</p>
  
  <ul>
  <li>Press play button to play Demo.mp4 on the top-left of the entire window</li>
  <li>Press Pause to pause</li>
  <li>Press full_screen to enter full screen (if QMediaPlayer can enter/quit full screen itself, then this feature is not necessary)</li>
  <li>press rearrange to put the playing window from top-left to top-right</li>
  <li>additional: fast forward and rewind (again, if QVideoPlayer or something Qt provided not already has this feature) </li>
  </ul>