Question

我的问题是如何将两个组合框连接在一起。原因是我希望用户能够选择制造商品牌，并希望下一个组合框显示链接到该制造商的汽车。然后我希望将数据放入jtextarea以显示给用户。这也适用于我的程序中的jlists。

package rlc.building.program;
/*
 *
 * @author Jacob
 */
public class GUI extends javax.swing.JFrame {

/**
 * Creates new form GUI
 */
public GUI() {
    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() {

    jScrollPane2 = new javax.swing.JScrollPane();
    jList2 = new javax.swing.JList();
    jScrollPane3 = new javax.swing.JScrollPane();
    jTextArea1 = new javax.swing.JTextArea();
    jLabel1 = new javax.swing.JLabel();
    jLabel2 = new javax.swing.JLabel();
    jLabel3 = new javax.swing.JLabel();
    jLabel4 = new javax.swing.JLabel();
    jLabel5 = new javax.swing.JLabel();
    jScrollPane1 = new javax.swing.JScrollPane();
    jList1 = new javax.swing.JList();
    jButton1 = new javax.swing.JButton();
    jComboBox3 = new javax.swing.JComboBox();
    jComboBox4 = new javax.swing.JComboBox();

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

    jList2.setModel(new javax.swing.AbstractListModel() {
        String[] strings = { "LED Light Bar £250", "Rally Light Hood Mount £150", "Rally Lights x2 £100", "Limo Tinted Windows £1500", "Custom Exo-Skelton Roll Cage £3000", "Custom Roll-Cage £1000", "Thick White Wall Tires £1450", "Front and Rear Strut Bars £400", " ", " " };
        public int getSize() { return strings.length; }
        public Object getElementAt(int i) { return strings[i]; }
    });
    jScrollPane2.setViewportView(jList2);

    jTextArea1.setColumns(20);
    jTextArea1.setRows(5);
    jScrollPane3.setViewportView(jTextArea1);

    jLabel1.setFont(new java.awt.Font("Arial", 1, 14)); // NOI18N
    jLabel1.setText("Real Life Car Building Program");

    jLabel2.setFont(new java.awt.Font("Tahoma", 0, 12)); // NOI18N
    jLabel2.setText("Modifications");
    jLabel2.setToolTipText("This area below is a list of all the modifications you can choose from for any vehicle.");

    jLabel3.setFont(new java.awt.Font("Tahoma", 0, 12)); // NOI18N
    jLabel3.setText("Manufacturers");
    jLabel3.setToolTipText("The car companys that you can choose from.");

    jLabel4.setFont(new java.awt.Font("Tahoma", 0, 12)); // NOI18N
    jLabel4.setText("Vehicles");
    jLabel4.setToolTipText("The vehicles you can choose from.");

    jLabel5.setFont(new java.awt.Font("Tahoma", 0, 12)); // NOI18N
    jLabel5.setText("Parts");
    jLabel5.setToolTipText("The parts that you can install on the vehicle straight from the manufacturer.");

    jList1.setModel(new javax.swing.AbstractListModel() {
        String[] strings = { "Leather Seats £1000", "New Stainless Steel Exhaust £500", "Alloy Wheels £1200", "Checker Plated Steel Panels £400", " " };
        public int getSize() { return strings.length; }
        public Object getElementAt(int i) { return strings[i]; }
    });
    jScrollPane1.setViewportView(jList1);

    jButton1.setFont(new java.awt.Font("Arial", 0, 12)); // NOI18N
    jButton1.setText("Reset");
    jButton1.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton1ActionPerformed(evt);
        }
    });

    jComboBox3.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "Chevrolet", "Dodge", "Ford", "Honda", "Infiniti", "Land Rover", "Mazda", "Mitsubishi", "Nissan", "Pontiac", "Scion", "Subaru", "Toyota", "Volkswagen" }));
    jComboBox3.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jComboBox3ActionPerformed(evt);
        }
    });

    jComboBox4.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "Item 1", "Item 2", "Item 3", "Item 4" }));

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addGap(208, 208, 208)
            .addComponent(jLabel1)
            .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        .addGroup(layout.createSequentialGroup()
            .addGap(59, 59, 59)
            .addComponent(jLabel3)
            .addGap(163, 163, 163)
            .addComponent(jLabel5)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
            .addComponent(jLabel2)
            .addGap(93, 93, 93))
        .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
            .addContainerGap()
            .addComponent(jScrollPane3)
            .addGap(18, 18, 18)
            .addComponent(jButton1)
            .addGap(26, 26, 26))
        .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGroup(layout.createSequentialGroup()
                    .addContainerGap()
                    .addComponent(jComboBox3, javax.swing.GroupLayout.PREFERRED_SIZE, 173, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGroup(layout.createSequentialGroup()
                    .addContainerGap()
                    .addComponent(jComboBox4, javax.swing.GroupLayout.PREFERRED_SIZE, 173, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGroup(layout.createSequentialGroup()
                    .addGap(71, 71, 71)
                    .addComponent(jLabel4)))
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 240, Short.MAX_VALUE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addComponent(jScrollPane2, javax.swing.GroupLayout.PREFERRED_SIZE, 241, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addContainerGap())
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 43, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addGap(14, 14, 14)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addComponent(jLabel2, javax.swing.GroupLayout.Alignment.TRAILING)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel5)
                    .addComponent(jLabel3)))
            .addGap(11, 11, 11)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGroup(layout.createSequentialGroup()
                    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 73, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGroup(layout.createSequentialGroup()
                            .addComponent(jComboBox3, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                            .addGap(3, 3, 3)
                            .addComponent(jLabel4)
                            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                            .addComponent(jComboBox4, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)))
                    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addGroup(layout.createSequentialGroup()
                            .addGap(47, 47, 47)
                            .addComponent(jButton1)
                            .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
                        .addGroup(layout.createSequentialGroup()
                            .addGap(18, 18, 18)
                            .addComponent(jScrollPane3, javax.swing.GroupLayout.DEFAULT_SIZE, 129, Short.MAX_VALUE)
                            .addContainerGap())))
                .addGroup(layout.createSequentialGroup()
                    .addComponent(jScrollPane2, javax.swing.GroupLayout.PREFERRED_SIZE, 73, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addGap(0, 0, Short.MAX_VALUE))))
    );

    pack();
}// </editor-fold>                        

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    jTextArea1.setText("");
}                                        

private void jComboBox3ActionPerformed(java.awt.event.ActionEvent evt) {                                           

}                                          

/**
 * @param args the command line arguments
 */




public static void main(String args[]) {
    /* Set the Nimbus look and feel */
    //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
    /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
     * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
     */
    try {
        for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
                javax.swing.UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    } catch (ClassNotFoundException ex) {
        java.util.logging.Logger.getLogger(GUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        java.util.logging.Logger.getLogger(GUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        java.util.logging.Logger.getLogger(GUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(GUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }
    //</editor-fold>

    /* Create and display the form */

    java.awt.EventQueue.invokeLater(new Runnable() {
        public void run() {
            new GUI().setVisible(true);
        }
    });



}



// Variables declaration - do not modify                     
private javax.swing.JButton jButton1;
private javax.swing.JComboBox jComboBox3;
private javax.swing.JComboBox jComboBox4;
private javax.swing.JLabel jLabel1;
private javax.swing.JLabel jLabel2;
private javax.swing.JLabel jLabel3;
private javax.swing.JLabel jLabel4;
private javax.swing.JLabel jLabel5;
private javax.swing.JList jList1;
private javax.swing.JList jList2;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JScrollPane jScrollPane2;
private javax.swing.JScrollPane jScrollPane3;
private javax.swing.JTextArea jTextArea1;
// End of variables declaration                   
}

代码适用于我已经构建的GUI。我只需填写骨头即可使程序正常运行。

Answer 1

原因是我希望用户能够选择一个制造商品牌和下一个组合框显示汽车与该制造商有关。

一些提示：

创建一个Manufacturer POJO类，其中包含制造商的数据以及包含相关汽车的列表。
将Manufacturer个对象列表添加到第一个组合框模型中。
根据第一个组合中选择的Manufacturer获取其关联汽车的列表，并填充第二个组合框模型。
根据在第二个组合框中选择的Car设置文本区域的文本以显示其数据。

你必须：

为两个组合框提供ItemListener或ActionListener。
至少为第一个组合框提供自定义ListCellRenderer。

建议读数

How to Use Combo Boxes
Handling Events on a Combo Box
Providing a Custom Renderer
Combo Box With Custom Renderer（Rob Camick饰演）

如何将两个jComboBox链接在一起并将数据显示到jtextarea中？

1 个答案:

建议读数