public class MyPanel extends JPanel
implements MouseMotionListener, ActionListener
{
 private MyFrame myFrame;
 int red,green,blue;
 JButton bclear = new JButton("clear");
 JButton bred = new JButton("red");
 JButton bgreen = new JButton("green");
 JButton bblue = new JButton("blue");
 public MyPanel(MyFrame myFrame)
 {
  super();
  this.myFrame = myFrame;
  myPanel.add(bclear); //ここでmyPanelを使えるようにしたい(アクセサーを利用らしいです)
  myPanel.add(bred);
  myPanel.add(bgreen);
  myPanel.add(bblue);
  bclear.addActionListener(this);
  bred.addActionListener(this);
  bgreen.addActionListener(this);
  bblue.addActionListener(this);
  
  addMouseMotionListener(this);
  setPreferredSize(new Dimension(640, 480));
 }