java - 如何询问 JButton 是否是 JButton 数组的一部分？

Question

如何询问数组中的某个按钮是否属于矩阵？例如这个。

JButton matrix = new JButton[8][8];

如何询问数组中的某个按钮是否属于矩阵？例如这个。

matrix[i+2][j-1]

任何帮助将不胜感激，我对java真的很陌生，并且没有向我解释任何内容。所以我一直在挣扎。

Answer 1

最好的解决方案是仅将按钮数组类型的 ActionListener(或更好的 AbstractAction)提供给实际上位于数组中的 JButton。换句话说，单独的 ActionListener 或 AbstractActions 用于单独的行为。分而治之!

例如:

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.*;

@SuppressWarnings("serial")
public class GuiEg extends JPanel {
   private static final String[][] BUTTON_TXTS = { 
      { "1", "2", "3" },
      { "4", "5", "6" }, 
      { "7", "8", "9" }, 
      { "", "0", "" } };
   private JButton[][] calcButtons = new JButton[BUTTON_TXTS.length][BUTTON_TXTS[0].length];

   public GuiEg() {
      // get rid of magic numbers
      setLayout(new BorderLayout(5, 5));
      add(createEastPanel(), BorderLayout.EAST);
      add(createCenterPanel(), BorderLayout.CENTER);
   }

   private JComponent createEastPanel() {
      JPanel eastPanel = new JPanel(new GridLayout(0, 1));
      eastPanel.add(new JButton(new AbstractAction("Start") {

         @Override
         public void actionPerformed(ActionEvent e) {
            System.out.println("Start has been pressed!");
         }
      }));
      eastPanel.add(new JButton(new AbstractAction("Stop") {

         @Override
         public void actionPerformed(ActionEvent e) {
            System.out.println("Stop has been pressed!");
         }
      }));
      eastPanel.add(new JButton(new AbstractAction("Pause") {

         @Override
         public void actionPerformed(ActionEvent e) {
            System.out.println("Pause has been pressed!");
         }
      }));
      eastPanel.add(new JButton(new AbstractAction("Exit") {

         @Override
         public void actionPerformed(ActionEvent e) {
            Window win = SwingUtilities.getWindowAncestor(GuiEg.this);
            win.dispose();
         }
      }));
      return eastPanel;
   }

   private JComponent createCenterPanel() {
      int rows = BUTTON_TXTS.length;
      int cols = BUTTON_TXTS[0].length;
      JPanel centerPanel = new JPanel(new GridLayout(rows , cols));
      ActionListener calcListener = new CalcListener(); 
      for (int r = 0; r < BUTTON_TXTS.length; r++) {
         for (int c = 0; c < BUTTON_TXTS[r].length; c++) {
            String text = BUTTON_TXTS[r][c];
            if (!text.isEmpty()) {
               calcButtons[r][c] = new JButton(text);
               calcButtons[r][c].addActionListener(calcListener);
               centerPanel.add(calcButtons[r][c]);
            } else {
               centerPanel.add(new JLabel());
            }
         }
      }
      return centerPanel;
   }

   private class CalcListener implements ActionListener {
      @Override
      public void actionPerformed(ActionEvent evt) {
         System.out.println(evt.getActionCommand() + " button pressed!");
      }
   }

   private static void createAndShowGui() {
      GuiEg mainPanel = new GuiEg();

      JFrame frame = new JFrame("GuiEg");
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.getContentPane().add(mainPanel);
      frame.pack();
      frame.setLocationByPlatform(true);
      frame.setVisible(true);
   }

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