当打开相同 window 的多个实例时，将数据传递到所需的 window Java

Question

有人请帮助我

我正在使用一个 java 应用程序制作销售发票。我已经在下面复制了我的部分代码的工作示例。此应用程序包含一个带有菜单项的主 window，单击该菜单项时，将打开一个带有组合框的“促销”window select 项。在 selecting 项目上将打开一个弹出窗口以显示 select 价格，然后打开另一个弹出窗口以显示 select 数量。在 selecting Qty 时，销售单 Window 中的 table 将填写 Item、Price 和 Qty。

当打开多个销售 Windows 时，数量 window 中的数据将转到最后打开的销售 window。有什么方法可以将数据传递给旧的销售 window，通过鼠标单击将其置于最前面？

import java.awt.EventQueue;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;

import javax.swing.JComboBox;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.table.DefaultTableModel;

 public class Main extends JFrame {
    private static JPanel contentPane;
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    Main frame = new Main();
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }
    public Main() {
        setTitle("Menu");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBounds(500, 500, 500, 425);
        setLocationRelativeTo(null);
        contentPane = new JPanel();
        contentPane.setLayout(null);
        
        JMenuBar menuBar = new JMenuBar();
        setJMenuBar(menuBar);
        
        JMenu mnSales = new JMenu("Sales");
        menuBar.add(mnSales);
        
        JMenuItem mntmProcessSale = new JMenuItem("Generate Sales Invoice");
        mntmProcessSale.addActionListener( e -> {
            Sale frame = new Sale(this);
            frame.setVisible(true);
        });
        mnSales.add(mntmProcessSale);
    }
    
    public static class Sale extends JDialog {
        private JComboBox combobox;
        private JLabel lbl;
        private static JTable table;

        public Sale(JFrame sale) {
            super(sale);
            setTitle("Sale");
            setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);
            setBounds(500, 500, 400, 400);
            setLocationRelativeTo(null);
            contentPane = new JPanel();
            contentPane.setLayout(null);
            setContentPane(contentPane);
            
            lbl=new JLabel("Select Item");
            lbl.setBounds(30, 30, 100, 20);
            contentPane.add (lbl);
          
            String [] item = {"A","B","C","D"};
            combobox=new JComboBox(item);
            combobox.addItemListener(new ItemListener() {
                @Override
                public void itemStateChanged(ItemEvent e) {
                    if(e.getStateChange() == ItemEvent.SELECTED) {
                        String s= (String) combobox.getSelectedItem();
                        Price.Item(s);
                        combobox.setSelectedIndex(-1);
                        new Price(sale).setVisible(true);
                    }
                }
            });
            combobox.setBounds(30, 50, 200, 20);
            combobox.setSelectedIndex(-1);
            contentPane.add (combobox);
            
            JScrollPane scrollPane= new JScrollPane();
            scrollPane.setBounds(20, 80, 250, 150);
            contentPane.add(scrollPane);
            
            table=new JTable();
            table.setModel(new DefaultTableModel(
                    new Object[][] {
                    },
                    new String[] {
                        "Item","Price", "Qty"
                    }
                ));
            scrollPane.setViewportView(table);
           
            
        }
        
        public static void filltable(Object[] row) {
        
            DefaultTableModel tm1 = (DefaultTableModel)table.getModel();
            tm1.addRow(row);
            System.out.println(row);
        }   
    }
    
    public static class Price extends JDialog {
        private JComboBox combobox;
        private JLabel lbl;
        private JPanel contentPane1;
        static String Item =null;

        public Price(JFrame price) {
            super(price);
            setTitle("Price");
            setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);
            setBounds(500, 500, 300, 300);
            contentPane1 = new JPanel();
            contentPane1.setLayout(null);
            setLocationRelativeTo(null);
            setContentPane(contentPane1);
            
            lbl=new JLabel("Select Price");
            lbl.setBounds(30, 30, 100, 20);
            contentPane1.add (lbl);
          
            String [] Price = {"5","10","20","30"};
            combobox=new JComboBox(Price);
            combobox.addItemListener(new ItemListener() {
                @Override
                public void itemStateChanged(ItemEvent e) {
                    if(e.getStateChange() == ItemEvent.SELECTED) {
                        String s= (String) combobox.getSelectedItem();
                        Qty.Price(Item,s);
                        combobox.setSelectedIndex(-1);
                        new Qty(price).setVisible(true);
                        dispose();
                    }
                }
            });
            combobox.setBounds(30, 50, 200, 20);
            combobox.setSelectedIndex(-1);
            contentPane1.add (combobox);   
        }
        public static void Item(String item) {
            Item=item;
        }
    }
    
    public static class Qty extends JDialog {
        private JComboBox combobox;
        private JLabel lbl;
        private JPanel contentPane2;
        static String Item =null;
        static String Price =null;

        public Qty(JFrame qty) {
            super(qty);
            setTitle("Qty");
            setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);
            setBounds(500, 500, 300, 300);
            setLocationRelativeTo(null);
            contentPane2 = new JPanel();
            contentPane2.setLayout(null);
            setContentPane(contentPane2);
            
            lbl=new JLabel("Select Qty");
            lbl.setBounds(30, 30, 100, 20);
            contentPane2.add (lbl);
          
            String [] Qty = {"1","2","3","4"};
            combobox=new JComboBox(Qty);
            combobox.addItemListener(new ItemListener() {
                @Override
                public void itemStateChanged(ItemEvent e) {
                    if(e.getStateChange() == ItemEvent.SELECTED) {
                        
                        String qty= (String) combobox.getSelectedItem();
                        
                        Sale.filltable(new Object[] {Item,Price,qty});
                        
                        dispose();
                    }
                }
            });
            combobox.setBounds(30, 50, 200, 20);
            combobox.setSelectedIndex(-1);
            contentPane2.add (combobox);   
        }
        public static  void Price(String item, String price) {
            Item=item; Price=price;
        }
    }
    
    }

Answer 1

您的销售 class 静态引用了您正在填写的 table。这意味着 Sale 的所有实例共享相同的 table 引用 - 而这个 table 引用实际上属于上次打开的销售 window。这是一个主要错误，也是非常糟糕的做法。

我假设您将方法 fillTable 设为静态，因为您没有在 QTY 对话框中引用 Sale 对象。而这个静态方法导致静态字段。

我认为你必须阅读模型-视图-控制器范式并重新设计你的程序。

您当前的问题很容易解决：

table class 销售 private final。
将 Sale 对象作为构造函数参数传递给 Qty 对话框。然后你可以在ot.

Answer 2

每个人和他的狗都给他们的名字命名 class Main。我把名字改成了OthrMain.
不要在每次单击“销售”菜单项时都创建另一个 Sale 实例。我在 class OthrMain.

salesDlg

HIDE_ON_CLOSE 是 JDialog 的默认值，因此无需明确设置。
不需要显式设置 JDialog 内容窗格，所以不要这样做。
不要使用静态变量将数据从一个对象传递到另一个对象。如果您想将“销售额”JDialog 中的值传递给“价格”JDialog，则向“价格”JDialog 添加一个方法，即“销售额”JDialog 可以打电话。
不要使用空布局。使用适当的 layout managers
每个 JDialog 的所有者应该是打开它的 JDialog。例如，“价格”JDialog 的所有者应该是“销售”JDialog.

我相信下面的代码可以满足您的需求。

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;

import javax.swing.JComboBox;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.table.DefaultTableModel;

public class OthrMain extends JFrame {
    private Sale  saleDlg;

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    OthrMain frame = new OthrMain();
                    frame.setVisible(true);
                }
                catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    public OthrMain() {
        setTitle("Menu");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(500, 425);
        setLocationByPlatform(true);
        JMenuBar menuBar = new JMenuBar();
        setJMenuBar(menuBar);
        JMenu mnSales = new JMenu("Sales");
        menuBar.add(mnSales);
        JMenuItem mntmProcessSale = new JMenuItem("Generate Sales Invoice");
        mntmProcessSale.addActionListener(e -> {
            if (saleDlg == null) {
                saleDlg = new Sale(this);
            }
            saleDlg.setVisible(true);
        });
        mnSales.add(mntmProcessSale);
    }

    public static class Sale extends JDialog {
        private JComboBox<String> combobox;
        private JLabel lbl;
        private final JTable table;
        private Price  priceDlg;

        public Sale(JFrame sale) {
            super(sale);
            setTitle("Sale");
            setSize(400, 400);
            setLocationRelativeTo(sale);
            JPanel topPanel = new JPanel();
            lbl = new JLabel("Select Item");
            topPanel.add(lbl);

            String[] item = {"A", "B", "C", "D"};
            combobox = new JComboBox<>(item);
            combobox.addItemListener(e -> {
                if (e.getStateChange() == ItemEvent.SELECTED) {
                    if (priceDlg == null) {
                        priceDlg = new Price(Sale.this);
                    }
                    priceDlg.setVisible(true);
                }
            });
            combobox.setSelectedIndex(-1);
            topPanel.add(combobox);
            add(topPanel, BorderLayout.PAGE_START);

            JScrollPane scrollPane = new JScrollPane();
            add(scrollPane, BorderLayout.CENTER);

            table = new JTable();
            table.setModel(new DefaultTableModel(new Object[][]{},
                                                 new String[]{"Item", "Price", "Qty"}));
            scrollPane.setViewportView(table);
        }

        public void filltable(Object price, Object qty) {
            Object[] row = new Object[3];
            row[0] = combobox.getSelectedItem();
            combobox.setSelectedIndex(-1);
            row[1] = price;
            row[2] = qty;
            DefaultTableModel tm1 = (DefaultTableModel) table.getModel();
            tm1.addRow(row);
        }
    }

    public static class Price extends JDialog {
        private JComboBox<String> combobox;
        private JLabel lbl;
        private Qty  qtyDlg;

        public Price(JDialog price) {
            super(price);
            setTitle("Price");
            setSize(300, 300);
            setLocationRelativeTo(price);
            JPanel panel = new JPanel();
            lbl = new JLabel("Select Price");
            panel.add(lbl);

            String[] prices = {"5", "10", "20", "30"};
            combobox = new JComboBox<>(prices);
            combobox.addItemListener(new ItemListener() {
                @Override
                public void itemStateChanged(ItemEvent e) {
                    if (e.getStateChange() == ItemEvent.SELECTED) {
                        if (qtyDlg == null) {
                            qtyDlg = new Qty(Price.this);
                        }
                        qtyDlg.setVisible(true);
                    }
                }
            });
            combobox.setSelectedIndex(-1);
            panel.add(combobox);
            add(panel, BorderLayout.PAGE_START);
        }

        public void clearPrice() {
            combobox.setSelectedIndex(-1);
        }

        public Object getPrice() {
            return combobox.getSelectedItem();
        }
    }

    public static class Qty extends JDialog {
        private JComboBox<String> combobox;
        private JLabel lbl;

        public Qty(JDialog qty) {
            super(qty);
            setTitle("Qty");
            setSize(300, 300);
            setLocationRelativeTo(qty);
            JPanel contentPane2 = new JPanel();

            lbl = new JLabel("Select Qty");
            contentPane2.add(lbl);

            String[] Qty = {"1", "2", "3", "4"};
            combobox = new JComboBox<>(Qty);
            combobox.addItemListener(this::fillTable);
            combobox.setSelectedIndex(-1);
            contentPane2.add(combobox);
            add(contentPane2);
        }

        public void fillTable(ItemEvent event) {
            if (event.getStateChange() == ItemEvent.SELECTED) {
                Object qty = combobox.getSelectedItem();
                combobox.setSelectedIndex(-1);
                Object price = ((Price) getOwner()).getPrice();
                ((Price) getOwner()).clearPrice();
                ((Sale) getOwner().getOwner()).filltable(price, qty);
                setVisible(false);
                getOwner().setVisible(false);
            }
        }
    }
}

当打开相同 window 的多个实例时，将数据传递到所需的 window Java

Pass data to desired window when multiple instances of same window are opened Java

java

swing

multiple-instances