Java 2 ME GameCanvas —如何接收所有keyPressed事件？

class CalculatorCanvas extends GameCanvas
{
    public CalculatorCanvas() throws java.io.IOException
    {
        super(true);
        setFullScreenMode(true);

        cursor = new Sprite(Image.createImage(\"/cursor.png\"));
    }

    public void paint(Graphics g)
    {
        g.setColor(0);
        g.fillRect(0, 0, getWidth(), getHeight());
        cursor.paint(g);
    }

    protected void keyPressed(int keyCode)
    {
        System.out.println(\"keyPressed: \" + getKeyName(key));
        if (keyCode == getKeyCode(RIGHT))
            cursor.move(STEP, 0);
        if (key == getKeyCode(LEFT))
            cursor.move(-STEP, 0);
            /*...*/
        repaint();
    }

    private final int STEP = 3;
    private Sprite cursor;
}