Java jMenuItem ActionListiner

尊敬的先生 以下代码中的问题是什么 地位

我想执行jMenuItem ActionListiner操作

对于新客户jMenuItem，它工作，但对于删除客户jMenuItem，它不工作

我执行了代码，但没有得到我想要的正确输出

主菜单代码

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
public class MainMenu extends JFrame implements ActionListener
{ 
    //Constructor   
public MainMenu() 
{
    JMenuBar menuBar = new JMenuBar();
    this.setJMenuBar(menuBar);
    this.setVisible(true);
    this.setSize(646,401);
    this.setResizable( false );
    this.setTitle("Shree Datta Digambar");
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    JMenu customer=new JMenu("Customer");
    menuBar.add(customer);
    JMenu paper=new JMenu("Paper");
    menuBar.add(paper);
    JMenu edit=new JMenu("Edit");
    menuBar.add(edit);              
    JMenu view=new JMenu("View");
    menuBar.add(view); 
    JMenu bill=new JMenu("Bill");
    menuBar.add(bill);
    JMenu help=new JMenu("Help");
    menuBar.add(help);

   JMenuItem newItem = new JMenuItem("New Customer");
    customer.add(newItem);
    JMenuItem deleteItem = new JMenuItem("Delete Customer");
    customer.add(deleteItem);

    JMenuItem addpaperItem = new JMenuItem("Add Paper");
    paper.add(addpaperItem);
    JMenuItem deletepaperItem = new JMenuItem("Delete Paper");
    paper.add(deletepaperItem);

    JMenuItem customer_detail = new JMenuItem("Customer Detail");
    edit.add(customer_detail);
    JMenuItem paper_detail = new JMenuItem("Paper Detail");
    edit.add(paper_detail);

    JMenuItem perticular_customer_detail = new JMenuItem("Perticular Customer Detail");
    view.add(perticular_customer_detail);

    JMenuItem customer_bill = new JMenuItem("Customer Bills");
    bill.add(customer_bill);   
    newItem.addActionListener(this);  
    newItem.setActionCommand("New Customer"); 
    deleteItem.addActionListener(this);  
    deleteItem.setActionCommand("Delete Customer");
}
    public void actionPerformed(ActionEvent e) 
    {     
        if(e.getActionCommand().equals("New Customer"))
        {         
            System.out.println("clicked new customer menu");  
            MainMenu.this.dispose(); 
            New_Customer nn = new New_Customer() {}; 
        }
        else if(e.getActionCommand().equals("Delete Customer"))   
        {                                 
            System.out.println("clicked new customer menu");  
            MainMenu.this.dispose(); 
            Delete_Customer ntn = new Delete_Customer(); 
        } 
    }
public static void main(String arg[])
{
    MainMenu menu1= new MainMenu();
}   
}

import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import javax.swing.*;
 public class Delete_Customer extends JFrame implements ActionListener
 {
JTextField tx1;
JLabel l1;
JLabel l2;
JButton b1;
Container c = getContentPane();
Delete_Customer()
{
    super("Shree Datta Digambar");
    setBounds(140,50,525,450);
    c.setLayout(null);
    tx1 = new JTextField(); 
l1 = new JLabel("Delete Customer Entry");
l2 = new JLabel("Building No");     
l1.setBounds(10,10,340,20);
l2.setBounds(10,20,140,70);
tx1.setBounds(10,70,90,20);     
b1 = new JButton("Ok"); 
b1.setBounds(110,70,70,20);
c.add(b1);
    c.add(l1);
c.add(l2);
    c.add(tx1);        
setVisible(true);
setDefaultCloseOperation(EXIT_ON_CLOSE);
    b1.addActionListener(this);        
}    
 public void actionPerformed(ActionEvent e)
        {

            System.out.println("You clicked the button");
            if(e.getSource()==b1)
            {
                try 
                {
                    Connection con;
                    Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
                    con = DriverManager.getConnection("jdbc:odbc:Dalvi");
                    try 
                    {

                        java.sql.Statement st = con.createStatement();
                        PreparedStatement ps = con.prepareStatement("DELETE FROM customer_details " + " WHERE Customer_Id = ?");                            
                        ps.setString(1,tx1.getText());
                        int string = ps.executeUpdate();
                        tx1.setText("");
                        JOptionPane.showMessageDialog(null,"You Successfully Deleted The Customer");                           
                    } 
                    catch (SQLException s) 
                    {
                        System.out.println("SQL code does not execute.");
                        JOptionPane.showMessageDialog(null,"Please Enter the Detail Correctly");   
                    }
                } 
                catch (ClassNotFoundException | SQLException ee) 
                {
                    System.out.println("Error:connection not created");
                    JOptionPane.showMessageDialog(null,"Please Enter the Detail Correctly");
                }
            }

            }

public static void main(String args[])
{
    Delete_Customer dc = new Delete_Customer();
}
}

删除客户代码

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
public class MainMenu extends JFrame implements ActionListener
{ 
    //Constructor   
public MainMenu() 
{
    JMenuBar menuBar = new JMenuBar();
    this.setJMenuBar(menuBar);
    this.setVisible(true);
    this.setSize(646,401);
    this.setResizable( false );
    this.setTitle("Shree Datta Digambar");
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    JMenu customer=new JMenu("Customer");
    menuBar.add(customer);
    JMenu paper=new JMenu("Paper");
    menuBar.add(paper);
    JMenu edit=new JMenu("Edit");
    menuBar.add(edit);              
    JMenu view=new JMenu("View");
    menuBar.add(view); 
    JMenu bill=new JMenu("Bill");
    menuBar.add(bill);
    JMenu help=new JMenu("Help");
    menuBar.add(help);

   JMenuItem newItem = new JMenuItem("New Customer");
    customer.add(newItem);
    JMenuItem deleteItem = new JMenuItem("Delete Customer");
    customer.add(deleteItem);

    JMenuItem addpaperItem = new JMenuItem("Add Paper");
    paper.add(addpaperItem);
    JMenuItem deletepaperItem = new JMenuItem("Delete Paper");
    paper.add(deletepaperItem);

    JMenuItem customer_detail = new JMenuItem("Customer Detail");
    edit.add(customer_detail);
    JMenuItem paper_detail = new JMenuItem("Paper Detail");
    edit.add(paper_detail);

    JMenuItem perticular_customer_detail = new JMenuItem("Perticular Customer Detail");
    view.add(perticular_customer_detail);

    JMenuItem customer_bill = new JMenuItem("Customer Bills");
    bill.add(customer_bill);   
    newItem.addActionListener(this);  
    newItem.setActionCommand("New Customer"); 
    deleteItem.addActionListener(this);  
    deleteItem.setActionCommand("Delete Customer");
}
    public void actionPerformed(ActionEvent e) 
    {     
        if(e.getActionCommand().equals("New Customer"))
        {         
            System.out.println("clicked new customer menu");  
            MainMenu.this.dispose(); 
            New_Customer nn = new New_Customer() {}; 
        }
        else if(e.getActionCommand().equals("Delete Customer"))   
        {                                 
            System.out.println("clicked new customer menu");  
            MainMenu.this.dispose(); 
            Delete_Customer ntn = new Delete_Customer(); 
        } 
    }
public static void main(String arg[])
{
    MainMenu menu1= new MainMenu();
}   
}

import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import javax.swing.*;
 public class Delete_Customer extends JFrame implements ActionListener
 {
JTextField tx1;
JLabel l1;
JLabel l2;
JButton b1;
Container c = getContentPane();
Delete_Customer()
{
    super("Shree Datta Digambar");
    setBounds(140,50,525,450);
    c.setLayout(null);
    tx1 = new JTextField(); 
l1 = new JLabel("Delete Customer Entry");
l2 = new JLabel("Building No");     
l1.setBounds(10,10,340,20);
l2.setBounds(10,20,140,70);
tx1.setBounds(10,70,90,20);     
b1 = new JButton("Ok"); 
b1.setBounds(110,70,70,20);
c.add(b1);
    c.add(l1);
c.add(l2);
    c.add(tx1);        
setVisible(true);
setDefaultCloseOperation(EXIT_ON_CLOSE);
    b1.addActionListener(this);        
}    
 public void actionPerformed(ActionEvent e)
        {

            System.out.println("You clicked the button");
            if(e.getSource()==b1)
            {
                try 
                {
                    Connection con;
                    Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
                    con = DriverManager.getConnection("jdbc:odbc:Dalvi");
                    try 
                    {

                        java.sql.Statement st = con.createStatement();
                        PreparedStatement ps = con.prepareStatement("DELETE FROM customer_details " + " WHERE Customer_Id = ?");                            
                        ps.setString(1,tx1.getText());
                        int string = ps.executeUpdate();
                        tx1.setText("");
                        JOptionPane.showMessageDialog(null,"You Successfully Deleted The Customer");                           
                    } 
                    catch (SQLException s) 
                    {
                        System.out.println("SQL code does not execute.");
                        JOptionPane.showMessageDialog(null,"Please Enter the Detail Correctly");   
                    }
                } 
                catch (ClassNotFoundException | SQLException ee) 
                {
                    System.out.println("Error:connection not created");
                    JOptionPane.showMessageDialog(null,"Please Enter the Detail Correctly");
                }
            }

            }

public static void main(String args[])
{
    Delete_Customer dc = new Delete_Customer();
}
}

感谢您在advanced中的帮助。

---

更重要的是，如果任何一位程序员想要推荐我的贡献，你可以。

在你的中删除客户代码

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
public class MainMenu extends JFrame implements ActionListener
{ 
    //Constructor   
public MainMenu() 
{
    JMenuBar menuBar = new JMenuBar();
    this.setJMenuBar(menuBar);
    this.setVisible(true);
    this.setSize(646,401);
    this.setResizable( false );
    this.setTitle("Shree Datta Digambar");
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    JMenu customer=new JMenu("Customer");
    menuBar.add(customer);
    JMenu paper=new JMenu("Paper");
    menuBar.add(paper);
    JMenu edit=new JMenu("Edit");
    menuBar.add(edit);              
    JMenu view=new JMenu("View");
    menuBar.add(view); 
    JMenu bill=new JMenu("Bill");
    menuBar.add(bill);
    JMenu help=new JMenu("Help");
    menuBar.add(help);

   JMenuItem newItem = new JMenuItem("New Customer");
    customer.add(newItem);
    JMenuItem deleteItem = new JMenuItem("Delete Customer");
    customer.add(deleteItem);

    JMenuItem addpaperItem = new JMenuItem("Add Paper");
    paper.add(addpaperItem);
    JMenuItem deletepaperItem = new JMenuItem("Delete Paper");
    paper.add(deletepaperItem);

    JMenuItem customer_detail = new JMenuItem("Customer Detail");
    edit.add(customer_detail);
    JMenuItem paper_detail = new JMenuItem("Paper Detail");
    edit.add(paper_detail);

    JMenuItem perticular_customer_detail = new JMenuItem("Perticular Customer Detail");
    view.add(perticular_customer_detail);

    JMenuItem customer_bill = new JMenuItem("Customer Bills");
    bill.add(customer_bill);   
    newItem.addActionListener(this);  
    newItem.setActionCommand("New Customer"); 
    deleteItem.addActionListener(this);  
    deleteItem.setActionCommand("Delete Customer");
}
    public void actionPerformed(ActionEvent e) 
    {     
        if(e.getActionCommand().equals("New Customer"))
        {         
            System.out.println("clicked new customer menu");  
            MainMenu.this.dispose(); 
            New_Customer nn = new New_Customer() {}; 
        }
        else if(e.getActionCommand().equals("Delete Customer"))   
        {                                 
            System.out.println("clicked new customer menu");  
            MainMenu.this.dispose(); 
            Delete_Customer ntn = new Delete_Customer(); 
        } 
    }
public static void main(String arg[])
{
    MainMenu menu1= new MainMenu();
}   
}

import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import javax.swing.*;
 public class Delete_Customer extends JFrame implements ActionListener
 {
JTextField tx1;
JLabel l1;
JLabel l2;
JButton b1;
Container c = getContentPane();
Delete_Customer()
{
    super("Shree Datta Digambar");
    setBounds(140,50,525,450);
    c.setLayout(null);
    tx1 = new JTextField(); 
l1 = new JLabel("Delete Customer Entry");
l2 = new JLabel("Building No");     
l1.setBounds(10,10,340,20);
l2.setBounds(10,20,140,70);
tx1.setBounds(10,70,90,20);     
b1 = new JButton("Ok"); 
b1.setBounds(110,70,70,20);
c.add(b1);
    c.add(l1);
c.add(l2);
    c.add(tx1);        
setVisible(true);
setDefaultCloseOperation(EXIT_ON_CLOSE);
    b1.addActionListener(this);        
}    
 public void actionPerformed(ActionEvent e)
        {

            System.out.println("You clicked the button");
            if(e.getSource()==b1)
            {
                try 
                {
                    Connection con;
                    Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
                    con = DriverManager.getConnection("jdbc:odbc:Dalvi");
                    try 
                    {

                        java.sql.Statement st = con.createStatement();
                        PreparedStatement ps = con.prepareStatement("DELETE FROM customer_details " + " WHERE Customer_Id = ?");                            
                        ps.setString(1,tx1.getText());
                        int string = ps.executeUpdate();
                        tx1.setText("");
                        JOptionPane.showMessageDialog(null,"You Successfully Deleted The Customer");                           
                    } 
                    catch (SQLException s) 
                    {
                        System.out.println("SQL code does not execute.");
                        JOptionPane.showMessageDialog(null,"Please Enter the Detail Correctly");   
                    }
                } 
                catch (ClassNotFoundException | SQLException ee) 
                {
                    System.out.println("Error:connection not created");
                    JOptionPane.showMessageDialog(null,"Please Enter the Detail Correctly");
                }
            }

            }

public static void main(String args[])
{
    Delete_Customer dc = new Delete_Customer();
}
}

请对主要方法发表评论。试试这个

import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import javax.swing.*;
public class Delete_Customer extends JFrame implements ActionListener
{
  JTextField tx1;
  JLabel l1;
 JLabel l2;
JButton b1;
Container c = getContentPane();
Delete_Customer()
{
 super("Shree Datta Digambar");
 setBounds(140,50,525,450);
 c.setLayout(null);
 tx1 = new JTextField(); 
l1 = new JLabel("Delete Customer Entry");
l2 = new JLabel("Building No");     
l1.setBounds(10,10,340,20);
l2.setBounds(10,20,140,70); 
tx1.setBounds(10,70,90,20);     
b1 = new JButton("Ok"); 
b1.setBounds(110,70,70,20);
c.add(b1);
c.add(l1);
c.add(l2);
c.add(tx1);        
setVisible(true);
setDefaultCloseOperation(EXIT_ON_CLOSE);
b1.addActionListener(this);        
}    
public void actionPerformed(ActionEvent e)
    {

        System.out.println("You clicked the button");
        if(e.getSource()==b1)
        {
            try 
            {
                Connection con;
                Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
                con = DriverManager.getConnection("jdbc:odbc:Dalvi");
                try 
                {

                    java.sql.Statement st = con.createStatement();
                    PreparedStatement ps = con.prepareStatement("DELETE FROM customer_details " + " WHERE Customer_Id = ?");                            
                    ps.setString(1,tx1.getText());
                    int string = ps.executeUpdate();
                    tx1.setText("");
                    JOptionPane.showMessageDialog(null,"You Successfully Deleted The Customer");                           
                } 
                catch (SQLException s) 
                {
                    System.out.println("SQL code does not execute.");
                    JOptionPane.showMessageDialog(null,"Please Enter the Detail Correctly");   
                }
            } 
            catch (ClassNotFoundException | SQLException ee) 
            {
                System.out.println("Error:connection not created");
                JOptionPane.showMessageDialog(null,"Please Enter the Detail Correctly");
            }
        }

        }

  /*public static void main(String args[]) 
 {
  Delete_Customer dc = new Delete_Customer();
 }*/   
}

---

你说的“没有得到我想要的正确输出”是什么意思？是否执行了Delete_Customer类？自动提交是正确的还是错误的？不要使用空布局，它们只会导致持续的问题更好地使用操作界面/抽象操作类进行菜单操作请查看