title: Display a QPixmap or QImage in ImageView in pyqtgraph
body: <p>I'm looking to display an array of RGBA in an ImageView. The only way I am currently able to do so is to make a QImage then a QPixmap and displaying it in a label. However I want it to be displayed in an ImageView to give it all of the other features that I have already implemented. Is this possible?</p>
  
  <pre><code>qimage = pg.fn.makeQImage(x)
  
  pixmap = QtGui.QPixmap.fromImage(qimage)
  
  imvOCTTopLeft.close()
  
  elasticity = QtGui.QLabel()
  
  layout.addWidget(elasticity,4,1)
  
  elasticity.setPixmap(pixmap)
  </code></pre>