我将如何使按钮是动态的取决于按钮的数量？

Question

import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
    
public class ButtonGrid{
    public static void main(String[] args) {
        int count = 26, i;
        JFrame frame = new JFrame("Title");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(1100,900);
        frame.setVisible(true);
        if (count >= 1 && count <= 30) {
            int rowcount = count / 10;
            frame.setLayout(new GridLayout(rowcount,10));
        
            for (i = 1; i <= count; i++) {
                frame.add(new JButton(""+i+""));
            }
        }
    }
}

我该怎么解决呢？

Answer 1

我制作了一个演示如何创建动态按钮jpanel的小GUI。

以下是初始状态：

下面是输入5个按钮后的状态：

我创建了一个JFrame和两个JPanels。输入JPanel使用BorderLayout和FlowLayout的组合来创建布局。按钮JPanel使用GridLayout。

下面是完整的可运行代码。

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

import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;

public class ButtonGrid implements Runnable {

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new ButtonGrid());
    }
    
    private JFrame frame;
    
    private JPanel buttonPanel;
    private JPanel inputPanel;
    
    private JTextField buttonCountField;

    @Override
    public void run() {
        frame = new JFrame("Button Grid");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        
        this.inputPanel = createInputPanel();
        frame.add(inputPanel, BorderLayout.BEFORE_FIRST_LINE);
        this.buttonPanel = createButtonPanel(30);
        frame.add(buttonPanel, BorderLayout.CENTER);
        
        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }
    
    private JPanel createInputPanel() {
        JPanel panel = new JPanel(new BorderLayout());
        panel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
        
        JPanel inputPanel = new JPanel(new FlowLayout());
        inputPanel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
        
        JLabel label = new JLabel("How many buttons? (1 - 30):");
        inputPanel.add(label);
        
        buttonCountField = new JTextField(5);
        inputPanel.add(buttonCountField);
        
        panel.add(inputPanel, BorderLayout.BEFORE_FIRST_LINE);
        
        JButton button = new JButton("Submit");
        panel.add(button, BorderLayout.AFTER_LAST_LINE);
        
        button.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent event) {
                int buttonCount = valueOf(buttonCountField.getText().trim());
                if (buttonCount >= 1 && buttonCount <= 30) {
                    createButtons(buttonPanel, buttonCount);
                }
            }
            
            private int valueOf(String number) {
                try {
                    return Integer.valueOf(number);
                } catch (NumberFormatException e) {
                    return -1;
                }
            }
        });
        
        return panel;
    }
    
    private JPanel createButtonPanel(int count) {
        JPanel panel = new JPanel(new GridLayout(0, 10, 5, 5));
        panel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
        createButtons(panel, count);
        
        return panel;
    }
    
    public void createButtons(JPanel panel, int count) {
        panel.removeAll();
        
        for (int index = 0; index < count; index++) {
            JButton button = new JButton(Integer.toString(index + 1));
            panel.add(button);
        }
        
        panel.validate();
        panel.repaint();
    }

}