title: Want to receive event even if not with focus
body: <p>I have a QGraphicsScene inside a QGraphicView.
  I want it to receive my keyboard event even if I didn't press on the screen.
  Because if I click anywhere on the screen with a key held I need to do another action, but now I need to click first, so I need to capture the event even if I'm not with the focus on the QGraphicsScene.
  I tried to put the event on the MainWindow, but it doesn't work.</p>
  
  <p>I get the event like that:</p>
  
  <pre><code>void AreaScene::keyPressEvent(QKeyEvent *event){
      if(event-&gt;key()==Qt::Key_Control){
          MapData::controlPress=true;
      }
  }
  void AreaScene::keyReleaseEvent(QKeyEvent *event){
      if(event-&gt;key()==Qt::Key_Control){
              MapData::controlPress=false;
              this-&gt;renderArea=false;
      }
  }
  </code></pre>