如何在Java中从JList变量获取文本

我试图获取从一个JList项传递到另一个JFrame的信息。我没有问题将JList中的第一个项目转移过来，但是一旦我添加了另一个项目，我就没有任何运气了。举个例子,

我的名单包括：

John Doe
Jane Doe

当选择John Doe时单击编辑按钮时，它会自动分配JList added Jane Doe（在本例中为Jane Doe）中最后一项的名字和姓氏字段。如何让它选择JList中所选项目的FirstName字段？我希望这是有意义的

注意：忽略集群代码

public class MainJPanel extends javax.swing.JPanel {

DefaultListModel contacts = new DefaultListModel();



/**
 * Creates new form JPanel
 */
public MainJPanel() {
    initComponents();
}

/**
 * This method is called from within the constructor to initialize the form.
 * WARNING: Do NOT modify this code. The content of this method is always
 * regenerated by the Form Editor.
 */
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">                          
private void initComponents() {

    firstNameLabel = new javax.swing.JLabel();
    lastNameLabel = new javax.swing.JLabel();
    firstNameField = new javax.swing.JTextField();
    lastNameField = new javax.swing.JTextField();
    jScrollPane1 = new javax.swing.JScrollPane();
    contactList = new javax.swing.JList();
    jPanel1 = new javax.swing.JPanel();
    editButton = new javax.swing.JButton();
    deleteButton = new javax.swing.JButton();
    addButton = new javax.swing.JButton();

    setBorder(javax.swing.BorderFactory.createTitledBorder("Add Contact"));

    firstNameLabel.setText("First Name:");

    lastNameLabel.setText("Last Name:");

    jScrollPane1.setViewportView(contactList);

    editButton.setText("Edit");
    editButton.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            editButtonActionPerformed(evt);
        }
    });

    deleteButton.setText("Delete");
    deleteButton.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            deleteButtonActionPerformed(evt);
        }
    });

    addButton.setText("Add");
    addButton.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            addButtonActionPerformed(evt);
        }
    });

    javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
    jPanel1.setLayout(jPanel1Layout);
    jPanel1Layout.setHorizontalGroup(
        jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(jPanel1Layout.createSequentialGroup()
            .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
            .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGroup(jPanel1Layout.createSequentialGroup()
                    .addGap(86, 86, 86)
                    .addComponent(editButton)
                    .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                    .addComponent(deleteButton))
                .addComponent(addButton)))
    );

    jPanel1Layout.linkSize(javax.swing.SwingConstants.HORIZONTAL, new java.awt.Component[] {addButton, deleteButton, editButton});

    jPanel1Layout.setVerticalGroup(
        jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(jPanel1Layout.createSequentialGroup()
            .addContainerGap()
            .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(addButton)
                .addComponent(deleteButton)
                .addComponent(editButton))
            .addContainerGap())
    );

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
    this.setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                .addComponent(firstNameLabel)
                .addComponent(lastNameLabel))
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addComponent(lastNameField)
                .addComponent(firstNameField))
            .addGap(6, 6, 6))
        .addGroup(layout.createSequentialGroup()
            .addGap(41, 41, 41)
            .addComponent(jScrollPane1))
        .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
            .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
            .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addContainerGap())
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addGap(21, 21, 21)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(firstNameLabel)
                .addComponent(firstNameField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addGap(18, 18, 18)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(lastNameLabel)
                .addComponent(lastNameField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addGap(18, 18, 18)
            .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 196, Short.MAX_VALUE)
            .addContainerGap())
    );
}// </editor-fold>                        

private void addButtonActionPerformed(java.awt.event.ActionEvent evt) {                                          
     contactList.setModel(contacts);
     Object fullName = firstNameField.getText() + " " + lastNameField.getText();
     contacts.addElement(fullName);


}                                         

private void deleteButtonActionPerformed(java.awt.event.ActionEvent evt) {                                             

        int reply = JOptionPane.showConfirmDialog(null, "Are you sure you want to delete this contact?", "Delete Contact?", JOptionPane.YES_NO_OPTION);

        if (reply == JOptionPane.YES_OPTION) {
            contacts.remove(contactList.getSelectedIndex());
        }     

}                                            

private void editButtonActionPerformed(java.awt.event.ActionEvent evt) {                                           

    EditJFrame frame = new EditJFrame();

    String editFirstNameField;
    String editLastNameField;
    int index = contactList.getSelectedIndex();

    editFirstNameField = (String) contactList.



    EditJFrame.editFirstNameField.setText(editFirstNameField);
    EditJFrame.editLastNameField.setText(editLastNameField);



    frame.setVisible(true);
}                                

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你能和我们分享整个课程吗？从通读开始，它会使你的代码更容易阅读。其次，您可能希望完成editFirstNameField=String联系人列表。行，因为不清楚您在做什么，也不清楚如何确定EditLastNameField它不会编译，因为行editFirstNameField=String contactList。不完整…您是否创建了类EditJFrame？若要更快获得更好的帮助，请发布一个。