所以我用Java制作了一个基于文本的RPG Applet.我正在使用SWING面板,上面有文本字段和按钮.我在Netbeans中编程,我正在使用GUI编辑器.我制作了HTML页面,它在浏览器中打开很好.当我单击按钮切换面板(基本上设置第一个不可见)时,新面板不会加载.我尝试使用repaint()和validate()但它只是不起作用…..任何帮助？

package applettest;

import javax.swing.UIManager;

public class NewApplet extends java.applet.Applet {

    startScreen ss;
    registerScreen rs;
    charactercreationScreen ccs;

    @Override
    public void init() {

        try {
            //This sets the look and feel to NIMBUS.
            UIManager.setLookAndFeel("com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel");
        } catch (Exception ex) {
            ex.printStackTrace();
        }
        try {
            java.awt.EventQueue.invokeAndWait(new Runnable() {

                @Override
                public void run() {
                    initComponents();
                    startup();
                }
            });
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }

    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
        this.setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 400, Short.MAX_VALUE)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 300, Short.MAX_VALUE)
        );
    }// </editor-fold>                        
    // Variables declaration - do not modify                     
    // End of variables declaration                   

    public void startup() {
        showCharacterCreationScreenSTART();
        showRegisterScreenSTART();
        showStartScreenSTART();
    }

    public void showStartScreen() {
        setSize(410, 350);
        ss = new applettest.startScreen(this);
        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
        this.setLayout(layout);
        layout.setHorizontalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).
                addComponent(ss, javax.swing.GroupLayout.PREFERRED_SIZE,
                javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));
        layout.setVerticalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).
                addComponent(ss, javax.swing.GroupLayout.PREFERRED_SIZE,
                javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));
    }

    public void showStartScreenSTART() {
        setSize(410, 350);
        rs.setVisible(false);
        ss = new applettest.startScreen(this);
        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
        this.setLayout(layout);
        layout.setHorizontalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).
                addComponent(ss, javax.swing.GroupLayout.PREFERRED_SIZE,
                javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));
        layout.setVerticalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).
                addComponent(ss, javax.swing.GroupLayout.PREFERRED_SIZE,
                javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));
        repaint();
        validate();
    }

    public void showRegisterScreen() {
        repaint();
        validate();
        ss.setVisible(false);
        setSize(400, 350);
        rs = new applettest.registerScreen(this);
        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
        this.setLayout(layout);
        layout.setHorizontalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).
                addComponent(rs, javax.swing.GroupLayout.PREFERRED_SIZE,
                javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));
        layout.setVerticalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).
                addComponent(rs, javax.swing.GroupLayout.PREFERRED_SIZE,
                javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));
        repaint();
        validate();
    }

    public void showRegisterScreenSTART() {
        repaint();
        validate();
        ccs.setVisible(false);
        setSize(400, 350);
        rs = new applettest.registerScreen(this);
        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
        this.setLayout(layout);
        layout.setHorizontalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).
                addComponent(rs, javax.swing.GroupLayout.PREFERRED_SIZE,
                javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));
        layout.setVerticalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).
                addComponent(rs, javax.swing.GroupLayout.PREFERRED_SIZE,
                javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));
        repaint();
        validate();
    }

    public void showCharacterCreationScreen() {
        rs.setVisible(false);
        setSize(400, 350);
        ccs = new applettest.charactercreationScreen(this);
        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
        this.setLayout(layout);
        layout.setHorizontalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).
                addComponent(ccs, javax.swing.GroupLayout.PREFERRED_SIZE,
                javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));
        layout.setVerticalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).
                addComponent(ccs, javax.swing.GroupLayout.PREFERRED_SIZE,
                javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));
        repaint();
        validate();

    }

    public void showCharacterCreationScreenSTART() {
        setSize(400, 350);
        ccs = new applettest.charactercreationScreen(this);
        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
        this.setLayout(layout);
        layout.setHorizontalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).
                addComponent(ccs, javax.swing.GroupLayout.PREFERRED_SIZE,
                javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));
        layout.setVerticalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).
                addComponent(ccs, javax.swing.GroupLayout.PREFERRED_SIZE,
                javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE));

    }
}

解决方法:

听起来你应该使用CardLayout.

也可以看看：

> How to Use CardLayout
> Java UI, trying to go to next page upon clicking button
> Dynamically Add Components to a JDialog