在actionPerformed（）方法中创建一个新的JFrame，然后如何使用此JFrame的JButton执行操作

Question

我是java的新手，我的问题是，可以使用JButton v，v1吗？ 在这个actionPerformed（）方法内部？ 如果有可能，那怎么办？ 提前致谢 。

PlaceOrder.java

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

class PlaceOrder extends JFrame implements ActionListener
{
JButton confirm,cancel,logOut;
JRadioButton rb1,rb2,rb3,rb4,rb5,rb6,rb7,rb8;
JTextField r1,r2,r3,r4,r5,r6,r7,r8;
JLabel Item,Quantity;
Food f[] = new Food[10];

double total = 0;

public PlaceOrder()
{
    f[0] = new Food("Chicken Burger",120);
    f[1] = new Food("Chicken BBQ Burger",150);
    f[2] = new Food("Chicken BBQ Cheese Burger",170);
    f[3] = new Food("Beef Burger",130);
    f[4] = new Food("Beef BBQ Burger",160);
    f[5] = new Food("Pizza",180);
    f[6] = new Food("Coffee",80);
    f[7] = new Food("Soft Drinks(Can)",35);

    setSize(700,700);
    setVisible(true);
    setLayout(null);

    rb1 = new JRadioButton("Chicken Burger");
    rb2 = new JRadioButton("Chicken BBQ Burger");
    rb3 = new JRadioButton("Chicken BBQ Cheese Burger");
    rb4 = new JRadioButton("Beef Burger");
    rb5 = new JRadioButton("Beef BBQ Burger");
    rb6 = new JRadioButton("Pizza");
    rb7 = new JRadioButton("Coffee");
    rb8 = new JRadioButton("Soft Drinks(Can)");

    rb1.setBounds(150,100,150,30);
    add(rb1);
    rb2.setBounds(150,130,150,30);
    add(rb2);
    rb3.setBounds(150,160,150,30);
    add(rb3);
    rb4.setBounds(150,190,150,30);
    add(rb4);
    rb5.setBounds(150,220,150,30);
    add(rb5);
    rb6.setBounds(150,250,150,30);
    add(rb6);
    rb7.setBounds(150,280,150,30);
    add(rb7);
    rb8.setBounds(150,310,150,30);
    add(rb8);

    r1 = new JTextField();
    r2 = new JTextField();
    r3 = new JTextField();
    r4 = new JTextField();
    r5 = new JTextField();
    r6 = new JTextField();
    r7 = new JTextField();
    r8 = new JTextField();

    Item = new JLabel("Item");
    Quantity = new JLabel("Quantity");

    Item.setBounds(160,20,100,50);
    add(Item);
    Quantity.setBounds(360,20,100,50);
    add(Quantity);

    r1.setBounds(350,100,150,20);
    add(r1);
    r2.setBounds(350,130,150,20);
    add(r2);
    r3.setBounds(350,160,150,20);
    add(r3);
    r4.setBounds(350,190,150,20);
    add(r4);
    r5.setBounds(350,220,150,20);
    add(r5);
    r6.setBounds(350,250,150,20);
    add(r6);
    r7.setBounds(350,280,150,20);
    add(r7);
    r8.setBounds(350,310,150,20);
    add(r8);

    confirm = new JButton("Order Status");
    cancel = new JButton("Cancel Order");
    logOut = new JButton("LogOut");

    confirm.setBounds(150,500,120,30);
    add(confirm);

    cancel.setBounds(380,500,120,30);
    add(cancel);

    logOut.setBounds(550,50,80,30);
    add(logOut);

    confirm.addActionListener(this);
    cancel.addActionListener(this);
    logOut.addActionListener(this);
}

public void actionPerformed(ActionEvent a)
{
    if(a.getSource() == confirm)
    {
        JFrame YourOrder = new JFrame();
        YourOrder.setSize(700,800);
        YourOrder.setLayout(null);
        YourOrder.setVisible(true);

        JLabel confirmation = new JLabel("Your Order");
        confirmation.setBounds(250,30,150,30);
        YourOrder.add(confirmation);

        JLabel s[] = new JLabel[3];
        s[0] = new JLabel("Item");
        s[0].setBounds(100,100,50,30);
        YourOrder.add(s[0]);
        s[1] = new JLabel("Quantity");
        s[1].setBounds(250,100,50,30);
        YourOrder.add(s[1]);
        s[2] = new JLabel("Total");
        s[2].setBounds(400,100,50,30);
        YourOrder.add(s[2]);

        JLabel l,l1,l2;
        JLabel netTotal = new JLabel("Net Amount  =  ");
        netTotal.setBounds(400,550,100,30);
        YourOrder.add(netTotal);

        JButton v,v1;
        v = new JButton("Change");
        v.setBounds(100,600,100,30);
        YourOrder.add(v);
        v.addActionListener(this);

        v1 = new JButton("Confirm Order");
        v1.setBounds(400,600,120,30);
        YourOrder.add(v1);
        v1.addActionListener(this);

        if(rb1.isSelected() && r1.getText() != "")
        {
            total = total + ((Integer.parseInt(r1.getText()))*(f[0].getFoodPrice()));
            l = new JLabel(rb1.getText());
            l.setBounds(100,150,100,30);
            YourOrder.add(l);

            l1 = new JLabel(r1.getText());
            l1.setBounds(250,150,100,30);
            YourOrder.add(l1);

            l2 = new JLabel(String.valueOf((Integer.parseInt(r1.getText()))*(f[0].getFoodPrice())));
            l2.setBounds(400,150,100,30);
            YourOrder.add(l2);
        }
        if(rb2.isSelected() && r2.getText() != "")
        {
            total = total + ((Integer.parseInt(r2.getText()))*(f[1].getFoodPrice()));
            l = new JLabel(rb2.getText());
            l.setBounds(100,200,100,30);
            YourOrder.add(l);

            l1 = new JLabel(r2.getText());
            l1.setBounds(250,200,100,30);
            YourOrder.add(l1);

            l2 = new JLabel(String.valueOf((Integer.parseInt(r2.getText()))*(f[1].getFoodPrice())));
            l2.setBounds(400,200,100,30);
            YourOrder.add(l2);
        }
        if(rb3.isSelected() && r3.getText() != "")
        {
            total = total + ((Integer.parseInt(r3.getText()))*(f[2].getFoodPrice()));
            l = new JLabel(rb3.getText());
            l.setBounds(100,250,100,30);
            YourOrder.add(l);

            l1 = new JLabel(r3.getText());
            l1.setBounds(250,250,100,30);
            YourOrder.add(l1);

            l2 = new JLabel(String.valueOf((Integer.parseInt(r3.getText()))*(f[2].getFoodPrice())));
            l2.setBounds(400,250,100,30);
            YourOrder.add(l2);
        }
        if(rb4.isSelected() && r4.getText() != "")
        {
            total = total + ((Integer.parseInt(r4.getText()))*(f[3].getFoodPrice()));
            l = new JLabel(rb4.getText());
            l.setBounds(100,300,100,30);
            YourOrder.add(l);

            l1 = new JLabel(r4.getText());
            l1.setBounds(250,300,100,30);
            YourOrder.add(l1);

            l2 = new JLabel(String.valueOf((Integer.parseInt(r4.getText()))*(f[3].getFoodPrice())));
            l2.setBounds(400,300,100,30);
            YourOrder.add(l2);
        }
        if(rb5.isSelected() && r5.getText() != "")
        {
            total = total + ((Integer.parseInt(r5.getText()))*(f[4].getFoodPrice()));
            l = new JLabel(rb5.getText());
            l.setBounds(100,350,100,30);
            YourOrder.add(l);

            l1 = new JLabel(r5.getText());
            l1.setBounds(250,350,100,30);
            YourOrder.add(l1);

            l2 = new JLabel(String.valueOf((Integer.parseInt(r5.getText()))*(f[4].getFoodPrice())));
            l2.setBounds(400,350,100,30);
            YourOrder.add(l2);
        }
        if(rb6.isSelected() && r6.getText() != "")
        {
            total = total + ((Integer.parseInt(r6.getText()))*(f[5].getFoodPrice()));
            l = new JLabel(rb6.getText());
            l.setBounds(100,400,100,30);
            YourOrder.add(l);

            l1 = new JLabel(r6.getText());
            l1.setBounds(250,400,100,30);
            YourOrder.add(l1);

            l2 = new JLabel(String.valueOf((Integer.parseInt(r6.getText()))*(f[5].getFoodPrice())));
            l2.setBounds(400,400,100,30);
            YourOrder.add(l2);
        }
        if(rb7.isSelected() && r7.getText() != "")
        {
            total = total + ((Integer.parseInt(r7.getText()))*(f[6].getFoodPrice()));
            l = new JLabel(rb7.getText());
            l.setBounds(100,450,100,30);
            YourOrder.add(l);

            l1 = new JLabel(r7.getText());
            l1.setBounds(250,450,100,30);
            YourOrder.add(l1);

            l2 = new JLabel(String.valueOf((Integer.parseInt(r7.getText()))*(f[6].getFoodPrice())));
            l2.setBounds(400,450,100,30);
            YourOrder.add(l2);
        }
        if(rb8.isSelected() && r8.getText() != "")
        {
            total = total + ((Integer.parseInt(r8.getText()))*(f[7].getFoodPrice()));
            l = new JLabel(rb8.getText());
            l.setBounds(100,500,100,30);
            YourOrder.add(l);

            l1 = new JLabel(r8.getText());
            l1.setBounds(250,500,100,30);
            YourOrder.add(l1);

            l2 = new JLabel(String.valueOf((Integer.parseInt(r8.getText()))*(f[7].getFoodPrice())));
            l2.setBounds(400,500,100,30);
            YourOrder.add(l2);
        }

        JLabel pay = new JLabel(String.valueOf(total));
        pay.setBounds(500,550,100,30);
        YourOrder.add(pay);

        if(a.getSource() == v)
        {
            YourOrder.setVisible(false);
        }
        else if(a.getSource() == v1)
        {
            JOptionPane.showMessageDialog(this,"Printing Invoice ...");
        }

    }
    else if(a.getSource() == cancel)
    {
        this.setVisible(false);
        PlaceOrder o1 = new PlaceOrder();
    }
    else
    {
        this.setVisible(false);
    }

}
}

Food.java

class Food 
{
private String foodName;
private double foodPrice;

public Food(String foodName,double foodPrice)
{
    this.foodName = foodName;
    this.foodPrice = foodPrice;
}

public String getFoodName()
{
    return this.foodName;
}

public double getFoodPrice()
{
    return this.foodPrice;
}
}

这两个类..

Answer 1

我的猜测：您希望能够在上面的代码映像v和v1中引用局部变量，但是对于该方法而言是局部的，它们的范围或“可见性”也仅限于该方法。 如果是这样，则从actionPerformed中获取该代码，并将其放入自己的类中，该类创建一个JPanel，该JPanel可以根据您的需要进行设置。 然后，您可以使该类的v和v1字段成为可能，并允许外部代码通过getter方法访问必要的属性。

如果您需要更多详细的帮助和较少的猜测，请再次发布可行的mcve 。 如果您这样做，我们可以与您合作，甚至有时可以帮助您增强代码。

其他问题：避免使用null布局和setBounds因为它们会导致僵化和难以增强的GUI，在您自己平台以外的大多数平台上，它们看起来都很糟糕。

还要检查“使用多个JFrame，良好/不良做法”吗？

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编辑

确认订单窗口应该是模式JDialog，而不是JFrame。 您希望程序停止运行，直到用户处理完之后才继续运行，这是模态对话框的作用。 另外，我将使用JSpinner而不是JTextFields来获取数量信息。 为什么？ 您必须始终假定用户是白痴，并且使用JSpinner可以防止用户输入非数字或其他不正确的信息。