java - 我如何通过按键连续移动到 ActionMap 中？

Question

我的代码有问题。我尝试做蛇游戏，但我停在了绘制面板的 Action map 的连续移动上。我尝试在循环中使用drawPanel.repaint，但它仅在到达末尾时向我显示，但我希望所有运动都在ActionMap中给出。我怎样才能做到呢？或者有人有其他解决方案吗？

    DrawPanel drawPanel = new DrawPanel();

    public Snake(){           
        InputMap inputMap = drawPanel.getInputMap();//JPanel.WHEN_IN_FOCUSED_WINDOW);
        ActionMap actionMap = drawPanel.getActionMap();                       
        inputMap.put(KeyStroke.getKeyStroke("RIGHT"), "rightAction");
        actionMap.put("rightAction", rightAction);            
        inputMap.put(KeyStroke.getKeyStroke("LEFT"), "leftAction");
        actionMap.put("leftAction", leftAction);            
        inputMap.put(KeyStroke.getKeyStroke("UP"), "upAction");
        actionMap.put("upAction", upAction);            
        inputMap.put(KeyStroke.getKeyStroke("DOWN"), "downAction");
        actionMap.put("downAction", downAction);

        add(drawPanel);            
        pack();
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        setVisible(true);
    }

    private class DrawPanel extends JPanel {

        protected void paintComponent(Graphics g) {                
            super.paintComponent(g);
            g.setColor(Color.GRAY);
                    g.fillRect(0, 0, getWidth(), getHeight());
            g.setColor(Color.GREEN);
            g.fillRect(x, y, 10, 10);    
        }
        public Dimension getPreferredSize() {
            return new Dimension(400, 400);
        }             
    }

    Action downAction = new AbstractAction(){
        public void actionPerformed(ActionEvent e) { 
            while (y<390)
            {              
                y +=+10;             
                drawPanel.repaint(); 
            }                
          /*  if (y<390)
                y +=+10; 
            else
                y = 390; 
            drawPanel.repaint();   
            */     
          }
    };

    Action upAction = new AbstractAction(){
        public void actionPerformed(ActionEvent e) {
            if (y>0)
                y -=10;
            else
                y = 0;
            drawPanel.repaint();
        }
    };

      Action leftAction = new AbstractAction(){
        public void actionPerformed(ActionEvent e) {
            if (x>0)
                x -=10;
            else
                x = 0;
            drawPanel.repaint();
        }
    };

    Action rightAction = new AbstractAction(){
        public void actionPerformed(ActionEvent e) {
            if (x<390)
                x +=10;
            else
                x = 390;
            drawPanel.repaint();
        }
    };    

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable(){
            public void run(){
                new Snake();
            }
        });
    }
}

Answer 1

如图here和 here ，您可以在 javax.swing.Timer 的 ActionListener 中调用您自己的 Action 实例的 actionPerformed() 方法。 。您可以调整计时器的延迟来调节动画的节奏。