title: add scrollbar in qt window?
body: <p>i have been learning qt from video tutorials <a href="https://www.youtube.com/watch?v=6KtOzh0StTc&amp;feature=youtube_gdata_player" rel="nofollow noreferrer">here</a>.
  i have completed 35 videos. So i wanted to create a sample application just to understand qt.
  i am using the latest version of qt creator.</p>
  
  <p>i added some <strong>push-buttons</strong> &amp; deleted the menu bar &amp; tool bar in main window.</p>
  
  <p><img src="https://i.stack.imgur.com/40O8j.png" alt="enter image description here"></p>
  
  <p>after running i found that if i resize the window scroll-bars don't appear. </p>
  
  <p><img src="https://i.stack.imgur.com/6xA2j.png" alt="enter image description here"></p>
  
  <p>i don't want the push-buttons to resize or move. i am fine with them becoming invisible but i want the scroll-bars so that the user can scroll to the invisible parts.
  i added a scroll area widget but it doesn't work. i did some coding by searching on internet but that didn't work either. when i increase the size of scroll area upto the window size; after running the window appears blank. maybe the push-buttons go 'below' the scroll-area. how do i change which object should be on 'top'?</p>
  
  <p>also since i am just a beginner, i don't know whats the best approach in designing using qt. should i just put the required widgets using designer &amp; then give their characteristics by coding? or should i do complete designing using designer? or should i abandon designer &amp; do the complete coding?
  THANK YOU!</p>
  
  <p><strong>edit</strong>
  @Synxis,
  that didnt help much. I even used the secentralwidget(ui->scrollareacontentswidget);
  i tried deleting the centralwidget QWidget, but i cant.
  Any solution?</p>
  
  <p><img src="https://i.stack.imgur.com/aWDBV.png" alt="enter image description here"></p>