Question

目前，我遇到了这个代码的问题，我希望每次我都向地图添加一个点，将JPanel添加到数组Panels（这是一个JPanel数组）。

我无法使用for语句，因为我想每次调用添加1个Jpanel（addPanel（）），而且我还面临动作侦听器的问题，它只识别第一个元素数组是正常的，因为JPanel没有添加到数组中。

import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.*;
import javax.swing.border.EmptyBorder;
import java.awt.BorderLayout;

public class TestGrid02 extends JPanel  {

   private static final long serialVersionUID = 1L;

   protected static final Color SELECTION_COLOR = Color.pink;
   private Color originalColor = new Color(238,238,238) ;
   private static final Dimension PREF_SIZE = new Dimension(50, 50);
   public JPanel panel_2;
   public JPanel panel_3;
   public JFrame frame;
   public JTextField textField;
   public int maxX =10;
   public int maxY =10;
   public String name;
   JPanel[] panels = new JPanel[100];


   public TestGrid02() {
       initUI();
       createMap(panel_2,maxX ,maxY );

   }

   public final void initUI() {

       setLayout(new BorderLayout(0, 0));

        panel_2 = new JPanel();
        add(panel_2, BorderLayout.WEST);
        panel_2.setLayout(new GridLayout(10, 10, 1, 1));
        panel_2.setBackground(Color.GRAY);

        panel_3 = new JPanel(new BorderLayout(4, 4));
        add(panel_3, BorderLayout.LINE_END);
        panel_3.setBackground(Color.GREEN);

        JPanel controls = new JPanel(new GridLayout(0, 1, 0, 25));
        panel_3.add(controls, BorderLayout.PAGE_START);
        controls.setBackground(Color.CYAN);
        controls.setBorder(new EmptyBorder(40, 20, 20, 20));
        controls.add(new JTextField(10));
        controls.add(new JTextField(10));
        controls.add(new JButton("OK"));
   }


   public void createMap(JPanel a,int maxX,int maxY)  {    

       String [ ][ ] map = new String [maxX][maxY];

      for (int x = maxX-1; x>=0 ; x--) {

          for (int y = 0; y<maxY  ; y++) { 
               int i=x-1;
               int j=y-1;

              map [x][y] =  i + ","+  j ;
              System.out.println( map [x][y]); 
              addPanel(a,i,j);

}}}

   public void addPanel(JPanel a,int c, int d) {
              int i =0;
              panels[i] = new JPanel();        
              a.add(panels[i]);
              panels[i].setPreferredSize(PREF_SIZE);
              name = String.format("[%d, %d]", c,d);
              panels[i].setBackground(originalColor);
              panels[i].setName(name); 
              System.out.println(  "PanelName:"+panels[i].getName());
              //panels[i] =panels[i]; 
              //I need this statement to add the panel to the array panels

              panels[i].addMouseListener(new MouseAdapter() {
                @Override
                public void mouseEntered(MouseEvent e) {
                    panels[i].setBackground(Color.pink);
                    panels[i].add(new JLabel(panels[i].getName()));

                    panels[i].repaint();
                    panels[i].revalidate();

                }

                @Override
                public void mouseExited(MouseEvent e) {
                    panels[i].setBackground(originalColor);
                    panels[i].repaint();
                    panels[i].removeAll();

                }
            });

   }   


   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {
         public void run() {
             JFrame frame = new JFrame("Astar");
             frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
             frame.getContentPane().add(new TestGrid02());
             frame.setLocationRelativeTo(null);
             frame.pack();
             frame.setVisible(true);     

         }
      });
   }
}

Answer 1

它只识别数组中的第一个元素

这是因为你所有的代码都引用了变量＆＃34; i＆＃34;这似乎永远不会改变。

从可见GUI添加（或删除）组件时，基本代码为：

panel.add(...);
panel.revalidate(); // to invoke the layout manager
panel.repaint();

不要使用阵列来固定面板。你正在限制自己的硬编码大小。而是使用ArrayList。或者真正的问题是你甚至需要一个数组来保存面板以供将来处理吗？

您的MouseListener代码错误。要引用生成事件的组件，您的代码应该是：

JPanel panel = (JPanel)e.getSource();
panel.setBackground(...);

如何将JPanels逐个添加到JPanel类型的数组中

1 个答案: