Java JFrame 意外地奇怪地删除组件

Question

我的 Java JFrame 项目的组件存在问题，删除了 JComboBox 在 space 中使用的所有内容。

我的程序中的bug视频示例可以直观查看here。

主要代码如下。您可以通过将 3 个面板替换为 random JCombobox(es) 并使用主 class 调用它来复制它。

如有任何帮助，我们将不胜感激。

package com.company;

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

public class DisplayPage extends JFrame implements ActionListener {

    EnterDetailsPage newRecord;
    ViewMore viewMoreRecord;
    ViewPage viewRecord;
    JPanel contentPanel = new JPanel(new FlowLayout());

    public DisplayPage(){
        setLayout(new BorderLayout());
        setSize(900, 600);
        setTitle("Add Flight Details");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        setPage(1);
        MenuSection menuSection = new MenuSection();

        //Add action listener to buttons
        menuSection.addNewButton.addActionListener(this::addActionPerformed);
        menuSection.updateButton.addActionListener(this::updateActionPerformed);
        menuSection.viewButton.addActionListener(this::viewActionPerformed);

        add("West", menuSection.getMainMenu());
        add("Center", contentPanel);
        setVisible(true);
    }

    public void setPage(int selection){
        contentPanel.removeAll();
        contentPanel.revalidate();
        //contentPanel.repaint();
        switch (selection) {
            case 1:
                newRecord = new EnterDetailsPage();
                contentPanel = newRecord.getTotalPanel();
                break;
            case 2:
                viewMoreRecord = new ViewMore();
                contentPanel = viewMoreRecord.getViewMorePanel();
                break;
            case 3:
                viewRecord = new ViewPage();
                contentPanel = viewRecord.getUpdatePagePanel();
                break;
        }
        add("Center", contentPanel);
    }

    public void actionPerformed(ActionEvent e){

    }

    public void addActionPerformed(ActionEvent e){
        setPage(1);
    }

    public void updateActionPerformed(ActionEvent e){
        setPage(2);
    }

    public void viewActionPerformed(ActionEvent e){
        setPage(3);
    }
}

Answer 1

与其费心制作自己的 GUI，不如查看 java 文档以检查是否有与您想要使用的类似的内容。无需制作您自己的 "MenuSection"，已经有 JTabbedPanes，您可以更轻松地使用它（没有闪烁和其他图形问题）。 https://docs.oracle.com/javase/tutorial/uiswing/components/tabbedpane.html

或者，您可以使用 CardLayout。 https://docs.oracle.com/javase/tutorial/uiswing/layout/card.html

CardLayout 示例：

public class DisplayPage extends JFrame implements ActionListener {
 ...

    CardLayout cl;
 ...

    public DisplayPage(){
     ...

        cl = new CardLayout();
        contentPanel.setLayout(cl);
     ...

        contentPanel.add(newRecord,"newRecord");
        contentPanel.add(viewMoreRecord,"viewMoreRecord");
        contentPanel.add(viewRecord,"viewRecord");
     ...
        cl.show(contentPanel,"newRecord");
     }


    public void addActionPerformed(ActionEvent e){
        cl.show(contentPanel,"newRecord");
    }

    public void updateActionPerformed(ActionEvent e){
        cl.show(contentPanel,"viewMoreRecord");
    }

    public void viewActionPerformed(ActionEvent e){
        cl.show(contentPanel,"viewRecord");
    }

Java JFrame 意外地奇怪地删除组件

Java JFrame Removing Components Weirdly by Accident

java

swing

jpanel

jframe

jcombobox