Question

根据在其他面板中找到的JPanel点击，我无法更新我的JList之一。我尝试过使用我在这里找到的代码：

repaint JPanel with every click at JList

但我还有问题。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();
    }
}

在我上面的迭代中，代码与链接中的代码不同。原因是我在那里尝试了代码;我完全复制并粘贴并通过它工作，没有任何反应。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。在我的情况下，它是一个面板中的列表，另一个面板添加到JFrame。就像我说的那样，上面的代码放弃了链接中找到的样本。相反，我尝试做的是创建面板将它们添加到框架，并通过更改其名称值编辑每次发生单击时我想要更改的面板; name值用于获取正确的文件。

Answer 1

调用repaint()对您的情况没有影响，因为在CharacterDetailsPanel的构造期间评估CharacterDetailsPanel中设置的名称，因此永远不会执行您的else分支。相反，您可以将JLabel存储在您将图像设置为成员的位置，并在调用setName时更新图像。

根据JList单击更改JPanel

1 个答案: