单击 JButton 创建 JButton

Question

我正在做一个项目，我需要点击一个按钮来制作另一个按钮。最终，我希望能够更好地控制新按钮的定位并能够多次创建新按钮，但是现在......我只想让一个 JButton 创建另一个 JButton。

使用下面的代码，我的目标是让白色 B1 创建红色 B3 按钮。我还想让蓝色 B2 按钮创建一个绿色 B4 按钮。

最终，我还希望 B3 和 B4（从按钮生成的按钮）让用户能够单击它们并使其消失。

这两个按钮似乎都不起作用，我不明白为什么。我有 3 个 class 个文件。知道我可能哪里出错了吗？

Window.Java

package gui;

import javax.swing.JFrame;

public class Window {

public static void main(String[] args) {

    //frame creation
    JFrame frame = new MainFrame("Button Create Button Test");

    //frame size
    frame.setSize(800, 800);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setVisible(true);

}
}

DetailsPanel.Java

package gui;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class DetailsPanel extends JPanel {
    public DetailsPanel() {
        Dimension size = getPreferredSize();
        size.width = 400;
        setPreferredSize(size);

        ///Buttons

        JButton button1 = new JButton("B1");
        button1.setPreferredSize(new Dimension (72, 73));
        button1.setBackground(Color.WHITE);
        button1.setBorderPainted(true);

        JButton button2 = new JButton("B2");
        button2.setPreferredSize(new Dimension (72, 73));
        button2.setBackground(Color.BLUE);
        button2.setBorderPainted(true);


        setLayout (new GridBagLayout());

        GridBagConstraints gc = new GridBagConstraints();

        /// Layout ///
        /// Row 1 ///

        gc.anchor = GridBagConstraints.NORTH;

        gc.weightx = 0.5;
        gc.weighty = 0.5;

        gc.gridx = 1;
        gc.gridy = 1;

        add(button1, gc);

        gc.gridx = 1;
        gc.gridy = 2;

        add(button2, gc);

        button1.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                JButton button3 = new JButton("B3");
                button3.setPreferredSize(new Dimension (72, 73));
                button3.setBackground(Color.RED);
                button3.setBorderPainted(true);

                gc.gridx = 1;
                gc.gridy = 3;

                add(button3, gc);
            }
        });

        button2.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                JButton button4 = new JButton("B3");
                button4.setPreferredSize(new Dimension (72, 73));
                button4.setBackground(Color.GREEN);
                button4.setBorderPainted(true);

                gc.gridx = 1;
                gc.gridy = 4;

                add(button4, gc);
            }
        });
    }
}

MainFrame.Java

    package gui;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JTextArea;

public class MainFrame extends JFrame {

    private DetailsPanel detailsPanel;

    public MainFrame(String title) {
        super(title);

        // set layout manager
        setLayout (new BorderLayout());

        // Create Swing Component
        detailsPanel = new DetailsPanel();
        detailsPanel.setBackground(Color.BLACK);

        // Add swing components to content pane
        Container container = getContentPane();

        container.add(detailsPanel, BorderLayout.WEST);



            }       
    }

Answer 1

您必须在添加按钮后触发布局管理器的重绘。

之后

  add(button3, gc);

添加

invalidate();
validate();

有关详细信息，请参阅 Swing 文档和 invalidate() 和 validate() 的 javadoc。

Answer 2

为了在点击按钮 B1 后显示按钮 B3，您需要添加...

revalidate();
repaint();

行后...

add(button3, gc);

在文件 DetailsPanel.java.
中同样适用于按钮 B2。

单击 JButton 创建 JButton

Creating a JButton with the click of a JButton

java

user-interface

swing

software-design

jbutton