title: Qt: QWidget doesn't show when running the application?
body: <p>My Qt application works fine and, finally yesterday, I manage to create the executable and it is ready for distribution. </p>
  
  <p>Today though, I want to add more features but whenever I try to add/remove a QWidget to the mainwindow.ui on Qt-designer, the changes never displayed when running the application in either release or debug mode !. It always shows me the old version (i.e.: before the modification)</p>
  
  <p>why does this happen and how to fix this ?</p>
  
  <p><strong>UPDATE:</strong></p>
  
  <p>I have to mention that after deploying my application, I changed the application name as follow:</p>
  
  <ol>
  <li>opened Qt-creator, in .pro file, change TARGET value  </li>
  <li>closed QT-creator, go to source folder and rename it  </li>
  <li>inside the source folder, renamed the .pro file too</li>
  </ol>
  
  <p>afterward, I realized that whenever I change anything in the Qt-Designer, these changes never take place when running the app.</p>