/// <summary>
 /// Gets executed when a port is being dragged
 /// </summary>
 /// <param name="port"></param>
 public void portDown(PortDrawing port)
 {
     portDrawingBeingDragged = port;
 }
 public void portUp(PortDrawing port)
 {
     if(connectionPossible(port.port)) {
         Connection connection = new Connection(portDrawingBeingDragged.port, port.port);
         circuitManager.addConnection(connection);
         refresh();
         unsavedChangesMade = true;
     }
 }