java - 从按钮数组中返回选择

Question

我有一个从 A-Z 创建按钮的数组，但我想在返回按下按钮的方法。

这是我的按钮原始代码:

String  b[]={"A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"};
for(i = 0; i < buttons.length; i++)
{
    buttons[i] = new JButton(b[i]);
    buttons[i].setSize(80, 80);
    buttons[i].setActionCommand(b[i]);
    buttons[i].addActionListener(new ActionListener(){
        public void actionPerformed(ActionEvent e) {
            String choice = e.getActionCommand();
            JOptionPane.showMessageDialog(null, "You have clicked: "+choice);
        }
    });
    panel.add(buttons[i]);
}

Answer 1

我不确定你的问题到底是什么，所以我有几个答案:

1. 如果您想将按钮创建拉入一个方法中 - 请参阅示例中的 getButton 方法

2. 如果您想在单击时访问实际的按钮，您可以使用 ActionEvent.getSource() 方法(未显示)或在单击期间将按钮标记为最终按钮来实现声明(如示例所示)。从那里你可以用按钮做任何你想做的事。

3. 如果您的问题是“我如何创建一个接受字母数组并将最后单击的按钮返回给我的方法”，您应该修改您的问题以明确说明这一点。我没有在这里回答这个问题，因为除非你有非常特殊的情况，否则这可能不是解决你正在处理的问题的好方法。您可以解释为什么需要这样做，我们可以建议更好的替代方案。

例子:

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class TempProject extends Box{
    /** Label to update with currently pressed keys */
    JLabel output = new JLabel();

    public TempProject(){
        super(BoxLayout.Y_AXIS);
        for(char i = 'A'; i <= 'Z'; i++){
            String buttonText = new Character(i).toString();
            JButton button = getButton(buttonText);
            add(button);
        }
    }

    public JButton getButton(final String text){
        final JButton button = new JButton(text);
        button.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e) {
                JOptionPane.showMessageDialog(null, "You have clicked: "+text);
                //If you want to do something with the button:
                button.setText("Clicked"); // (can access button because it's marked as final)
            }
        });
        return button;
    }

    public static void main(String args[])
    {
        EventQueue.invokeLater(new Runnable()
        {
            public void run()
            {
                JFrame frame = new JFrame();
                frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
                frame.setContentPane(new TempProject());    
                frame.pack();
                frame.setVisible(true);
                new TempProject();
            }
        });
    }   
}