setPreferredSize(getMinimumSize());
        public EnvelopeCanvas (EnvelopeNode [] e,Patch pa,JTextField[] f)        {super(); values=f;nodes=e;p=pa;    nodeX=new int[nodes.length];         setMinimumSize (new Dimension (300,50));         MyListener myListener = new MyListener ();         addMouseListener (myListener);         addMouseMotionListener (myListener);                  nodeY=new int[nodes.length];        }