根据 JList 点击更改 JPanel

Question

我无法根据在另一个面板中找到的JList单击来更新我的一个JPanel。我尝试使用我在这里找到的代码：

在JList上每次点击都重新粉刷JPanel

但我仍然有问题。我在下面粘贴了我的代码：

import javax.swing.ListSelectionModel;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
public class SelectionFrame extends JFrame {
    private BufferedImage backgroundImage;  
    private JList<Object> superClassList;
    private JPanel contentPane;
    private CharacterListPanel clp;
    private CharacterDetailsPanel cdp;
    private CardLayout card = new CardLayout();
    protected SelectionFrame() {
        // Create the background image
        try {
            backgroundImage = ImageIO.read(new File(GUIConfig.DEFAULT_GAME_BACKGROUND));
        } catch (Exception e) {
            e.printStackTrace();
        }
        // Set the title to the default
        setTitle(GUIConfig.DEFAULT_GAME_TITLE);
        // Set the frame background
        contentPane = new JPanel(){ 
            public void paintComponent(Graphics g) {
                Image img = Toolkit.getDefaultToolkit().getImage(Gui.class.getResource("/others/background_1.png"));  
                g.drawImage(img, 0, 0, this.getWidth(), this.getHeight(), this);  
               }  
        };
        contentPane.setBackground(new Color(238, 238, 238));
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        setContentPane(contentPane);
        // Add Character List Panel to JFrame
        clp = new CharacterListPanel();
        cdp = new CharacterDetailsPanel();
        add(clp, BorderLayout.LINE_START);
        add(cdp, BorderLayout.LINE_END);
        // Grab its list and store it in super class list
        superClassList = clp.getCharacterList();
        // List for change in list
        superClassList.getSelectionModel().addListSelectionListener(new ListSelectionListener() {
            @Override
            public void valueChanged(ListSelectionEvent e) {
                if (!e.getValueIsAdjusting()) {
                    String selectedVal = superClassList.getSelectedValue().toString();
                    System.out.println(selectedVal);
                    cdp.setName(selectedVal);
                    repaint();
                }
            }
        });
        // Set the size of the frame to the default, center frame, hide top level and do not allow resizing
        setSize(GUIConfig.DEFAULT_SELECTION_MENU_WIDTH, GUIConfig.DEFAULT_SELECTION_MENU_HEIGHT);
        setLocation(GUIConfig.HALF_DIMENSION_WIDTH - (int) this.getSize().getWidth()/2, GUIConfig.HALF_DIMENSION_HEIGHT - (int) this.getSize().getHeight()/2);
        setUndecorated(true);
        setResizable(false);
        pack();
        // Show frame
        setVisible(true);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
    }
    // This sub class is used to display the list of playable characters. it will include the character name and character icon
    class CharacterListPanel extends JPanel {
        private JList<Object> characterList;
        protected CharacterListPanel() {
            // Create list to hold name and icon for characters
            characterList = new JList<Object>();
            // Set list details
            characterList.setBorder(new LineBorder(Color.BLACK));
            characterList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
            // Map of characters
            Map<Object, ImageIcon> characters = new HashMap<Object, ImageIcon>();
            // Loop through default character names and retrieve character icon file paths
            for(int i = 0; i < GUIConfig.DEFAULT_CHARACTER_NAMES.size(); i+=1) {
                ImageIcon img = new ImageIcon(GUIConfig.DEFAULT_CHARACTER_SYMBOLS.get(GUIConfig.DEFAULT_CHARACTER_NAMES.get(i)));
                characters.put(GUIConfig.DEFAULT_CHARACTER_NAMES.get(i), img);
            }
            // Add items to the list
            characterList.setListData(GUIConfig.DEFAULT_CHARACTER_NAMES.toArray());
            characterList.setCellRenderer(new IconListRenderer(characters));
            // Add list to JPanel
            add(characterList);
            // Remove grey background of JPanel
            setOpaque(false);
        }
        protected JList<Object> getCharacterList() {
            return characterList;
        }
    }
    // This sub class is used to display the character details card based on what the user has selected in the list
    class CharacterDetailsPanel extends JPanel {
        private String name = null;
        protected CharacterDetailsPanel() {
            System.out.println(getName());
            if(getName() == null || getName().isEmpty()){
                try {
                    BufferedImage img = ImageIO.read(new File(GUIConfig.DEFAULT_CHARACTER_DETAILS.get("Default")));
                    JLabel picLabel = new JLabel(new ImageIcon(img));
                    add(picLabel);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            } else {
                try {
                    BufferedImage img = ImageIO.read(new File(GUIConfig.DEFAULT_CHARACTER_DETAILS.get(getName())));
                    JLabel picLabel = new JLabel(new ImageIcon(img));
                    add(picLabel);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

            // Remove grey background of JPanel
            setOpaque(false);
        }
        public String getName() {
            return name;
        }
        public void setName(String name) {
            this.name = name;
        }
    }
    public static void main(String[] args) {
        SelectionFrame sf = new SelectionFrame();
    }
}

在我当前的迭代中，上面的代码与链接中的代码不同。原因是我在那里尝试了代码;我从字面上复制和粘贴并按照我的方式工作，什么也没发生。我认为这是因为在他的情况下，它是一个直接添加到框架和面板的列表。就我而言，它是一个面板中的列表，另一个面板添加到JFrame中。所以就像我说的，上面的代码放弃了链接中找到的示例。相反，我尝试做的是创建面板将它们添加到框架中，并通过更改其名称值来编辑每次单击时想要更改的面板;名称值用于获取正确的文件。

Answer 1

调用

repaint()在您的情况下没有效果，因为在构造CharacterDetailsPanel期间会评估CharacterDetailsPanel中设置的名称，因此您的else分支永远不会被执行。相反，您可以存储将映像设置为成员的JLabel，并在调用 setName 时更新映像。