调用方法时java找不到图形变量？

Question

这是一个JButton，当单击它时需要有动作监听器，它将调用drawPiece方法。当前错误是connect find symbol变量g

JButton column3 = new JButton();
    column3.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        x = 2;
        //.drawPiece(g);
        column3.drawPiece(g);


      }
    });

这是drawPiece方法，在这里初始化图形

public void paintComponent(Graphics pen) {
    super.paintComponent(pen);
    drawBoard(pen);
    drawPiece(pen);
    boardarray();
  }

  public void drawPiece(Graphics g) {
    x = x;
    y=0;// fixed at 0
    int turn=0; 
    boolean p1Win = false;
    boolean p2Win = false;
    //while(p1Win==false && p2Win==false) {
      checkPiece();
      g.setColor(Color.RED);
      g.fillOval(10+x*110,10+y*110,100,100);
      //checkWin();     
      p1Win = true;
  }

如有任何建议，我们将不胜感激

Answer 1

column3.drawPiece(g);

您不应该直接从侦听器调用绘画方法。如果要重新绘制组件，请告诉组件重新绘制自身：

column3.repaint();

调用RepaintManager来计划重新绘制。最终paintComponent()方法将被相应的Graphics对象调用