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JList未在单独窗格中更新(Swing、Java)

jlist swing java
  •  0
  • frillybob  · 技术社区  · 9 年前

    在名为“密码库”的第一个选项卡上,我有一个JList,其中包含存储密码的“网站”列表。在第二个选项卡上,我有一个添加“密码”功能。当我添加密码时,JList仅在窗格中更新。当我切换回另一个选项卡“密码保险库”时,它尚未更新。当我重新启动该程序时,它已被更新。我使用字段,所以这不是局部变量的问题。 

    public final class PasswordManagerView1 extends JFrame
    implements PasswordManagerView, ListSelectionListener {
/**
 * JList.
 */
private JList<String> list;

/**
 * JButtons.
 */
private JButton enter, unlock, reset, buttonAddEnter;

/**
 * Controller.
 */
private PasswordManagerController controller;

/**
 * Dimensions.
 */
private Dimension maxSize;

/**
 * JTabbedPanes.
 */
private JTabbedPane tabbedPane;

/**
 * JTextField.
 */
private JTextField passwordDisplay, textField;

/**
 * PasswordField.
 */
private JPasswordField passwordField, resetField, passwordFieldadd;

/**
 * Useful Constants.
 */
private static final int MAX_SIZE_HORI = 800, MAX_SIZE_VERTI = 400,
        EMPTY_BORDER_SIZE = 5;

/**
 * Constructor.
 */
public PasswordManagerView1() {
    super("Password Manager");
    JTabbedPane tabbedPane = new JTabbedPane();
    //Initial JPanel creation
    tabbedPane.setBorder(
            new EmptyBorder(PasswordManagerView1.EMPTY_BORDER_SIZE,
                    PasswordManagerView1.EMPTY_BORDER_SIZE,
                    PasswordManagerView1.EMPTY_BORDER_SIZE,
                    PasswordManagerView1.EMPTY_BORDER_SIZE));
    this.maxSize = new Dimension(PasswordManagerView1.MAX_SIZE_HORI,
            PasswordManagerView1.MAX_SIZE_VERTI);
    tabbedPane.setPreferredSize(this.maxSize);
    this.getContentPane().add(tabbedPane);

    //Initial JTabbedPane creation

    //Tab creation
    JComponent panel1 = this.makePasswordVault();
    ImageIcon icon = new ImageIcon("lock-icon.png");
    tabbedPane.addTab("Password Vault", icon, panel1,
            "View the passwords in the vault");
    JComponent panel3 = this.makeAddPanel("Add Password");
    tabbedPane.addTab("Add Password", icon, panel3,
            "Add passwords to the vault");
    //JComponent panel2 = this.makeAddPanel("ALSO ADDS");
    //tabbedPane.addTab("Delete Password", icon, panel2,
    //        "Deletes a password from the vault");

    JComponent panel4 = this.makeInfoPanel();
    tabbedPane.addTab("Info", icon, panel4,
            "View settings and program info");
    //Pack up
    this.setResizable(false);
    this.pack();
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    this.setVisible(true);
}

@Override
public JComponent makeAddPanel(String text) {
    JPanel panel = new JPanel();
    panel.setLayout(null);
    //Creation of string array of with stores
    String[] listContentC = this.getStore();

    this.list = new JList<>(listContentC);
    this.list.setBounds(0, 0, 233, 360);
    JScrollPane pane = new JScrollPane(this.list);
    pane.setBounds(0, 0, 233, 360);
    panel.add(pane);
    JLabel labelAdd = new JLabel("Add Password");
    labelAdd.setHorizontalAlignment(SwingConstants.CENTER);
    labelAdd.setFont(new Font("Times New Roman", Font.PLAIN, 24));
    labelAdd.setBounds(427, 38, 163, 31);
    panel.add(labelAdd);

    this.passwordFieldadd = new JPasswordField();
    this.passwordFieldadd.setBounds(536, 100, 116, 22);
    panel.add(this.passwordFieldadd);

    this.textField = new JTextField();
    this.textField.setBounds(375, 100, 116, 22);
    panel.add(this.textField);

    JLabel lblWebsite = new JLabel("Website");
    lblWebsite.setHorizontalAlignment(SwingConstants.CENTER);
    lblWebsite.setFont(new Font("Times New Roman", Font.PLAIN, 13));
    lblWebsite.setBounds(401, 126, 56, 16);
    panel.add(lblWebsite);

    JLabel lblPassword = new JLabel("Password");
    lblPassword.setHorizontalAlignment(SwingConstants.CENTER);
    lblPassword.setFont(new Font("Times New Roman", Font.PLAIN, 13));
    lblPassword.setBounds(566, 126, 56, 16);
    panel.add(lblPassword);

    this.buttonAddEnter = new JButton("Enter");
    this.buttonAddEnter.setBounds(465, 161, 97, 25);
    panel.add(this.buttonAddEnter);
    this.buttonAddEnter.addActionListener(this);
    return panel;
}

@Override
public JComponent makeInfoPanel() {
    JPanel panel = new JPanel();
    panel.setLayout(new GridLayout(1, 1));
    StringBuilder toPrint = new StringBuilder();
    SimpleReader in = new SimpleReader1L("data/Notice.txt");
    while (!in.atEOS()) {
        toPrint.append(in.nextLine() + "\n");
    }
    String toPrintString = toPrint.toString();
    JTextArea noticeText = new JTextArea(toPrintString);
    noticeText.setEditable(false);
    JScrollPane noticeTextScroll = new JScrollPane(noticeText);
    panel.add(noticeTextScroll);
    in.close();
    return panel;

}

@Override
public JComponent makePasswordVault() {
    JPanel panel = new JPanel();
    panel.setLayout(null);
    /*
     * Ask for help on this.
     *
     * I would have liked to create the listContentC by passing nothing into
     * the controller and then the controller using the model to extract the
     * data from a text file. However, my array was always initialized to
     * something null and caused a runtime error.
     *
     *
     */

    //Creation of string array of with stores
    String[] listContentC = this.getStore();

    //GUI setup of list
    this.list = new JList<>(listContentC);
    this.list.setLayoutOrientation(JList.VERTICAL);
    this.list.addListSelectionListener(this);
    JScrollPane pane = new JScrollPane(this.list);
    pane.setBounds(0, 0, 233, 360);
    panel.add(pane);

    //The label creation (for instructions)
    JLabel labelA = new JLabel("the store and press enter!");
    labelA.setFont(new Font("Times New Roman", Font.PLAIN, 13));
    labelA.setBounds(294, 70, 157, 31);
    panel.add(labelA);
    JLabel labelB = new JLabel("To view a password, click on");
    labelB.setFont(new Font("Times New Roman", Font.PLAIN, 13));
    labelB.setBounds(284, 54, 163, 31);
    panel.add(labelB);

    //Enter button creation
    this.enter = new JButton("Enter");
    this.enter.setBounds(303, 128, 116, 25);
    panel.add(this.enter);
    this.enter.setEnabled(false);
    this.enter.addActionListener(this);

    //Password Display field creation
    this.passwordDisplay = new JTextField();
    this.passwordDisplay.setBackground(Color.WHITE);
    this.passwordDisplay.setEditable(false);
    this.passwordDisplay
            .setFont(new Font("Times New Roman", Font.PLAIN, 13));
    this.passwordDisplay.setHorizontalAlignment(SwingConstants.CENTER);
    this.passwordDisplay.setText("");
    this.passwordDisplay.setBounds(303, 247, 116, 22);
    panel.add(this.passwordDisplay);
    this.passwordDisplay.setColumns(10);

    //Password Label creation
    JLabel passwordLabel = new JLabel("Password:");
    passwordLabel.setHorizontalAlignment(SwingConstants.CENTER);
    passwordLabel.setFont(new Font("Times New Roman", Font.PLAIN, 13));
    passwordLabel.setBounds(336, 218, 56, 16);
    panel.add(passwordLabel);

    //Master password notice
    JLabel mastPass = new JLabel("Enter master password to unlock vault:");
    mastPass.setFont(new Font("Times New Roman", Font.PLAIN, 13));
    mastPass.setBounds(532, 54, 218, 31);
    panel.add(mastPass);

    //Password Field
    this.passwordField = new JPasswordField();
    this.passwordField.setBounds(532, 128, 116, 24);
    panel.add(this.passwordField);

    //Unlock button
    this.unlock = new JButton("Unlock");
    this.unlock.setFont(new Font("Times New Roman", Font.PLAIN, 13));
    this.unlock.setBounds(660, 127, 97, 25);
    panel.add(this.unlock);
    this.unlock.addActionListener(this);

    //New setup label
    JLabel labelC = new JLabel("Reset/Set up new master pass:");
    labelC.setHorizontalAlignment(SwingConstants.CENTER);
    labelC.setFont(new Font("Times New Roman", Font.PLAIN, 13));
    labelC.setBounds(532, 217, 218, 16);
    panel.add(labelC);

    //New setup label
    JLabel defaultLabel = new JLabel("Default Password = \"password\"");
    defaultLabel.setHorizontalAlignment(SwingConstants.CENTER);
    defaultLabel.setFont(new Font("Times New Roman", Font.PLAIN, 13));
    defaultLabel.setBounds(560, 77, 171, 16);
    panel.add(defaultLabel);

    this.resetField = new JPasswordField();
    this.resetField.setBounds(532, 246, 116, 24);
    panel.add(this.resetField);

    this.reset = new JButton("Update");
    this.reset.setFont(new Font("Times New Roman", Font.PLAIN, 13));
    this.reset.setBounds(660, 245, 97, 25);
    this.reset.setEnabled(false);
    panel.add(this.reset);
    this.reset.addActionListener(this);
    return panel;
}

@Override
public String[] getStore() {

    int storeCount = 0;
    SimpleReader in = new SimpleReader1L("data/store.txt");
    while (!in.atEOS()) {
        storeCount++;
        in.nextLine();
    }
    in.close();
    String[] listContentC = new String[storeCount];
    SimpleReader in2 = new SimpleReader1L("data/store.txt");
    for (int i = 0; i < storeCount; i++) {
        listContentC[i] = in2.nextLine();
    }
    in2.close();
    return listContentC;
}

@Override
public void registerObserver(PasswordManagerController controller) {
    this.controller = controller;
}

@Override
public void updateEnterButtonVaultTab(boolean result) {
    this.enter.setEnabled(result);
}

@Override
public void actionPerformed(ActionEvent event) {
    //Wait cursor
    this.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));

    //What button was pressed
    Object source = event.getSource();
    if (source == this.enter) {
        int index = this.list.getSelectedIndex();
        System.out.println(index);
        if (this.list.getSelectedIndex() != -1) {
            this.controller.processEnterEvent(this.list.getSelectedValue());
        }
    } else if (source == this.unlock) {
        this.controller
                .processUnlockEvent(this.passwordField.getPassword());
    } else if (source == this.reset) {
        this.controller.processResetEvent(this.resetField.getPassword());
    } else if (source == this.buttonAddEnter) {
        this.controller.processAddEvent(this.textField.getText(),
                this.passwordFieldadd.getPassword());
        //needs done in model
        this.updateListModel();
    }
    this.setCursor(Cursor.getDefaultCursor());
}

@Override
public void updateListModel() {
    //MOVE TO THE MODEL
    String[] temp = this.getStore();
    DefaultListModel<String> temp2 = new DefaultListModel<>();
    for (int i = 0; i < temp.length; i++) {
        temp2.addElement(temp[i]);
    }
    this.list.setModel(temp2);
}

@Override
public JTabbedPane getTabbedPane() {
    return this.tabbedPane;
}

@Override
public void setTabbedPane(JTabbedPane tabbedPane) {
    this.tabbedPane = tabbedPane;
}

@Override
public void updatePasswordField() {
    this.passwordField.setText("");
}

@Override
public void updateResetPasswordDisplay() {
    this.resetField.setText("");
}

@Override
public void displayWrongPass() {
    JOptionPane.showMessageDialog(this, "Wrong password entered!");

}

@Override
public void displayUpdatedPass() {
    JOptionPane.showMessageDialog(this, "Master password updated!");
}

@Override
public void updateResetButton(boolean result) {
    this.reset.setEnabled(result);
}

@Override
public void updatePasswordDisplay(char[] password) {
    StringBuilder passwordCreation = new StringBuilder();
    for (int i = 0; i < password.length; i++) {
        passwordCreation.append(password[i]);
    }
    this.passwordDisplay.setText(passwordCreation.toString());

}

@Override
public JComponent makeTextPanel(String text) {
    // TODO Auto-generated method stub
    return null;
}

@Override
public void valueChanged(ListSelectionEvent arg0) {

}

}
    3 回复  |  直到 9 年前
        1
  •  4
  •   FredK    9 年前

    构造函数调用makePasswordPanel(),其中包含以下行: 

       this.list = new JList<>(listContentC);

    然后构造函数调用makeAddPanel(),该函数具有以下行: 

    这list=新的JList<>(列表内容C);

    因此,现在您已经放弃了第一个列表的句柄,并将其替换为对新列表的引用。然后在updateListModel中,更改此的模型。列表(这是makeAddPanel列表)。无法同时更新密码面板的模型,因为您已经放弃了对该面板的引用。

        2
  •  1
  •   Community Mohan Dere    8 年前

    同样,要显示多个JList,所有的JList都显示相同的内容,那么所有的Jlist都应该共享相同的模型。如果您这样做,那么对一个JList所做的更改将反映在所有其他JList中,因为这些更改实际上并不是对JList本身所做的(它只显示模型的内容),而是对共享模型所做的。为了理解这一点,您需要阅读MVC或Model-View-Controller设计模式,因为Swing组件使用 变种 这一点。

    例如,请参阅下面的代码,其中我创建了3个JPanel,每个JPanel都有自己的JList,但它们都共享相同的内容 DefaultListModel<String> 注意,我有三个JPanel都是从一个父类扩展而来的,该父类实际上包含JList并在其构造函数中接受模型。然后,如果我在一个JPanel中添加列表项或在另一个JPpanel中删除列表项,它们都会显示在3个JPanels的所有列表中。还可以查看我是如何最小化代码,使其接近编译、运行和显示问题或解决方案所需的最小值的 minimal code example program 或MCVE: 

    import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import javax.swing.*;

@SuppressWarnings("serial")
public class PanelsWithSharedList extends JPanel {
    private static final int PREF_W = 400;
    private static final int PREF_H = 250;
    private JTabbedPane tabbedPane = new JTabbedPane();
    private DefaultListModel<String> listModel = new DefaultListModel<>();

    public PanelsWithSharedList() {
        for (int i = 0; i < 10; i++) {
            listModel.addElement("List element " + (i + 1));
        }

        setLayout(new BorderLayout());
        add(tabbedPane);
        tabbedPane.add("Panel 1", new ListShowingPanel1(listModel));
        tabbedPane.add("Panel 2", new ListShowingPanel2(listModel));
        tabbedPane.add("Panel 3", new ListShowingPanel3(listModel));
    }

    @Override
    public Dimension getPreferredSize() {
        Dimension superSz = super.getPreferredSize();
        if (isPreferredSizeSet()) {
            return superSz;
        }
        int prefW = Math.max(superSz.width, PREF_W);
        int prefH = Math.max(superSz.height, PREF_H);
        return new Dimension(prefW, prefH);
    }

    private static void createAndShowGui() {
        PanelsWithSharedList mainPanel = new PanelsWithSharedList();

        JFrame frame = new JFrame("Panels With Shared List");
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        frame.getContentPane().add(mainPanel);
        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> createAndShowGui());
    }
}

@SuppressWarnings("serial")
abstract class AbstractListShowingPanel extends JPanel {
    private JList<String> list;

    public AbstractListShowingPanel(DefaultListModel<String> listModel) {
        list = new JList<>(listModel);
        list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
    }

    public JList<String> getList() {
        return list;
    }

    public DefaultListModel<String> getModel() {
        return (DefaultListModel<String>) list.getModel();
    }
}

@SuppressWarnings("serial")
class ListShowingPanel1 extends AbstractListShowingPanel {
    private JTextField textField = new JTextField(10);

    public ListShowingPanel1(DefaultListModel<String> listModel) {
        super(listModel);
        add(new JScrollPane(getList()));
        add(new JLabel("Text to add:"));

        Action action = new AddTextAction();
        textField.setAction(action);
        add(textField);
        add(new JButton(action));

    }

    private class AddTextAction extends AbstractAction {
        public AddTextAction() {
            super("Add Text");
            putValue(MNEMONIC_KEY, KeyEvent.VK_A);
        }

        @Override
        public void actionPerformed(ActionEvent e) {
            getModel().addElement(textField.getText());
            textField.selectAll();
        }
    }

}

@SuppressWarnings("serial")
class ListShowingPanel2 extends AbstractListShowingPanel {
    public ListShowingPanel2(DefaultListModel<String> listModel) {
        super(listModel);
        add(new JScrollPane(getList()));
        add(new JButton(new DeleteItemAction()));
    }

    private class DeleteItemAction extends AbstractAction {
        public DeleteItemAction() {
            super("Delete Selected Item");
            putValue(MNEMONIC_KEY, KeyEvent.VK_D);
        }

        public void actionPerformed(ActionEvent e) {
            JList<String> list = getList();
            String selection = list.getSelectedValue();
            if (selection != null) {
                getModel().removeElement(selection);
            }
        }
    }
}

@SuppressWarnings("serial")
class ListShowingPanel3 extends AbstractListShowingPanel {
    public ListShowingPanel3(DefaultListModel<String> listModel) {
        super(listModel);
        setLayout(new BorderLayout());
        add(new JScrollPane(getList()));
    }
}
        3
  •  0
  •   Jorge_B    9 年前

    仅从学术角度来看,我建议将图形元素和底层数据模型之间的这种关系实现为观察者模式( https://en.wikipedia.org/wiki/Observer_pattern ). 当您开始使用5或6个GUI元素来响应同一共享数据结构中的更改时,您向我们展示的方法可能很快就会变得令人困惑和难以维护。

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