title: How to create a VTK Chart in a QVTKWidget
body: <p>I tried now for 2 hours creating a simple chart with vtk without any success. It just does not render anything and I cannot call the view->getRenderer()->render () function. It results in an exception.</p>
  
  <p>What I understood so far is:</p>
  
  <pre><code>vtkContextView* view = vtkContextView::New ();
  QVTKWidget*  widget = new QVTKWidget (); 
  widget-&gt;setRenderWindow (view-&gt;getRenderWindow ());
  </code></pre>
  
  <p>After creating chart and adding it...
      view->getRenderer ()->render ();</p>
  
  <p>I'm using vtk 7.1, qt 5.7 with vs15.</p>
  
  <p>I also tried to find a full example in the Internet but I haven't found any complete.</p>
  
  <p>Could someone show an example of how to create such a vtk chart with qt?</p>