Question

请承担我所犯的任何错误，因为我还是Java新手。我正在完成一项任务，而且我被困了。我需要创建一个基于java的GUI，可以用作零售计算器。我已完成所有标签和字段，以及一些ActionListener，但我在最后一部分工作中苦苦挣扎。

我需要将输入的数据存储到表中以供将来查看。我尝试过JTable，但我似乎无法做到。我的代码如下。任何帮助或建议将不胜感激。

/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package my.numberaddition;

/**
*
* @author Andrew
*/
public class NumberAdditionUI extends javax.swing.JFrame {

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

    jScrollPane1 = new javax.swing.JScrollPane();
    jTable1 = new javax.swing.JTable();
    jButton3 = new javax.swing.JButton();
    jLabel1 = new javax.swing.JLabel();
    originalPrice = new javax.swing.JTextField();
    jLabel2 = new javax.swing.JLabel();
    discountPercentage = new javax.swing.JTextField();
    salePrice = new javax.swing.JTextField();
    jLabel3 = new javax.swing.JLabel();
    jButton1 = new javax.swing.JButton();
    jButton2 = new javax.swing.JButton();
    jLabel4 = new javax.swing.JLabel();
    jSeparator1 = new javax.swing.JSeparator();
    jLabel5 = new javax.swing.JLabel();
    itemName = new javax.swing.JTextField();
    departmentName = new javax.swing.JComboBox();
    jLabel6 = new javax.swing.JLabel();
    scrollPane1 = new java.awt.ScrollPane();
    jLabel7 = new javax.swing.JLabel();

    jTable1.setModel(new javax.swing.table.DefaultTableModel(
        new Object [][] {
            {null, null, null, null},
            {null, null, null, null},
            {null, null, null, null},
            {null, null, null, null}
        },
        new String [] {
            "Title 1", "Title 2", "Title 3", "Title 4"
        }
    ));
    jScrollPane1.setViewportView(jTable1);

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

    jButton3.setText("Exit");
    jButton3.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton3ActionPerformed(evt);
        }
    });

    jLabel1.setText("Original Price:");

    originalPrice.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            originalPriceActionPerformed(evt);
        }
    });

    jLabel2.setText("Discount Percentage:");

    discountPercentage.setToolTipText("");
    discountPercentage.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            discountPercentageActionPerformed(evt);
        }
    });

    jLabel3.setText("Sale Price:");

    jButton1.setText("Calculate");
    jButton1.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton1ActionPerformed(evt);
        }
    });

    jButton2.setText("Next Item");
    jButton2.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton2ActionPerformed(evt);
        }
    });

    jLabel4.setFont(new java.awt.Font("Tahoma", 1, 18)); // NOI18N
    jLabel4.setText("Retail Calculator");

    jLabel5.setText("Item Name:");

    departmentName.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "Select Department", "Kitchen & Bath", "Mens Clothing", "Women's Clothing", "Electronics", "Hardware" }));
    departmentName.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            departmentNameActionPerformed(evt);
        }
    });

    jLabel6.setText("Department:");

    jLabel7.setFont(new java.awt.Font("Tahoma", 1, 18)); // NOI18N
    jLabel7.setText("Previously Calculated Items");

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
            .addGap(0, 0, Short.MAX_VALUE)
            .addComponent(jButton3)
            .addGap(19, 19, 19))
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addComponent(scrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addGroup(layout.createSequentialGroup()
                    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addGroup(layout.createSequentialGroup()
                            .addGap(19, 19, 19)
                            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                                .addGroup(layout.createSequentialGroup()
                                    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                                        .addComponent(jLabel1)
                                        .addComponent(jLabel2)
                                        .addComponent(jLabel3)
                                        .addComponent(jLabel5)
                                        .addComponent(jLabel6))
                                    .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                                    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                                        .addComponent(jButton1)
                                        .addComponent(jButton2)
                                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING, false)
                                            .addComponent(itemName, javax.swing.GroupLayout.Alignment.LEADING)
                                            .addComponent(salePrice, javax.swing.GroupLayout.Alignment.LEADING)
                                            .addComponent(discountPercentage, javax.swing.GroupLayout.Alignment.LEADING)
                                            .addComponent(originalPrice, javax.swing.GroupLayout.Alignment.LEADING, javax.swing.GroupLayout.PREFERRED_SIZE, 130, javax.swing.GroupLayout.PREFERRED_SIZE))
                                        .addComponent(departmentName, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)))
                                .addComponent(jLabel4)))
                        .addGroup(layout.createSequentialGroup()
                            .addGap(140, 140, 140)
                            .addComponent(jLabel7)))
                    .addGap(0, 114, Short.MAX_VALUE))
                .addComponent(jSeparator1, javax.swing.GroupLayout.Alignment.TRAILING))
            .addContainerGap())
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addComponent(jLabel4)
            .addGap(18, 18, 18)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(departmentName, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addComponent(jLabel6))
            .addGap(8, 8, 8)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGroup(layout.createSequentialGroup()
                    .addGap(6, 6, 6)
                    .addComponent(jLabel5))
                .addComponent(itemName, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(jLabel1)
                .addComponent(originalPrice, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(discountPercentage, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addComponent(jLabel2))
            .addGap(9, 9, 9)
            .addComponent(jButton1)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(jLabel3)
                .addComponent(salePrice, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addComponent(jButton2)
            .addGap(33, 33, 33)
            .addComponent(jSeparator1, javax.swing.GroupLayout.PREFERRED_SIZE, 10, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addComponent(jLabel7)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 11, Short.MAX_VALUE)
            .addComponent(scrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 229, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(jButton3)
            .addContainerGap())
    );

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

private void originalPriceActionPerformed(java.awt.event.ActionEvent evt) {                                              
    // TODO add your handling code here:
}                                             

private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {                                         
System.exit(0);
}                                        

private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    originalPrice.setText("");
    discountPercentage.setText("");
    salePrice.setText("");
    itemName.setText("");
    departmentName.setSelectedIndex(0);
}                                        

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    // First we define float variables.
    float num1, num2, result;
    // We have to parse the text to a type float.
    num1 = Float.parseFloat(originalPrice.getText());
    num2 = (Float.parseFloat(discountPercentage.getText()))/100;
    // Now we can perform the addition.
    result = num1-(num1*num2);
    // We will now pass the value of result to jTextField3.
    // At the same time, we are going to
    // change the value of result from a float to a string.
    salePrice.setText(String.valueOf(result));
}                                        

private void departmentNameActionPerformed(java.awt.event.ActionEvent evt) {                                               
    // TODO add your handling code here:
}                                              

private void discountPercentageActionPerformed(java.awt.event.ActionEvent evt) {                                                   
    // TODO add your handling code here:
}                                                  

/**
 * @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(NumberAdditionUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        java.util.logging.Logger.getLogger(NumberAdditionUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        java.util.logging.Logger.getLogger(NumberAdditionUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(NumberAdditionUI.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 NumberAdditionUI().setVisible(true);
        }
    });
}

// Variables declaration - do not modify                     
private javax.swing.JComboBox departmentName;
private javax.swing.JTextField discountPercentage;
private javax.swing.JTextField itemName;
private javax.swing.JButton jButton1;
private javax.swing.JButton jButton2;
private javax.swing.JButton jButton3;
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.JLabel jLabel6;
private javax.swing.JLabel jLabel7;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JSeparator jSeparator1;
private javax.swing.JTable jTable1;
private javax.swing.JTextField originalPrice;
private javax.swing.JTextField salePrice;
private java.awt.ScrollPane scrollPane1;
// End of variables declaration                   
}

Answer 1

处理表的最佳方法是创建一个扩展AbstractTableModel的TableModel类。所有数据操作都应在表模型对象中完成。当数据被更改时，您应该调用一些fireTable *方法。

将jTextFields保存到JTable

1 个答案: