选项＃1

Question

我这里有一个程序，用于计算二手车的成本，用户输入的价格和维修价格。每次我添加更多文本字段进行输入时，用户可以同时比较3辆汽车，程序在运行时看起来完全混乱。任何帮助将不胜感激。

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

public class Chapter4Summ extends JPanel implements ActionListener
{
static String name, price, repair;
static double tax1, price1, repair1, total1;
static double totalcost;

DecimalFormat y = new DecimalFormat ("$#,###,###,###.00");

public int count;
public double sum;
public double max;

public JTextField input, input2, input3, input4, input5, input6, input7, input8, input9;
public JLabel countDisplay;
public JLabel sumDisplay;
public JLabel maxDisplay;
public JLabel averageDisplay;


public void updateStats ()
{
    name = (input.getText ().trim ());
    repair1 = Double.parseDouble (input3.getText ().trim ());
    price1 = Double.parseDouble (input2.getText ().trim ());
    tax1 = price1 * 0.13;
    averageDisplay.setText ("" + y.format (tax1));

    total1 = tax1 + repair1 + price1;
    maxDisplay.setText ("" + y.format (total1));


}



public void reset ()
{
    count = 0;
    sum = 0;

    input.setText ("");
    input2.setText ("");
    input3.setText ("");
    countDisplay.setText ("0");
    sumDisplay.setText ("0");
    maxDisplay.setText ("");
    averageDisplay.setText ("");
}




public JButton computeButton;
public JButton resetButton;



public Chapter4Summ ()
{
    input = new JTextField (10);
    input.addActionListener (this);
    input2 = new JTextField (10);
    input.addActionListener (this);
    input3 = new JTextField (10);
    input.addActionListener (this);

    computeButton = new JButton ("Enter Information");
    computeButton.addActionListener (this);
    resetButton = new JButton ("Reset");
    resetButton.addActionListener (this);
    countDisplay = new JLabel ("0");
    sumDisplay = new JLabel ("0");
    maxDisplay = new JLabel ();
    averageDisplay = new JLabel ();
    countDisplay.setFont (new Font ("Serif", Font.BOLD, 16));
    sumDisplay.setFont (new Font ("Serif", Font.BOLD, 16));
    maxDisplay.setFont (new Font ("Serif", Font.BOLD, 16));
    averageDisplay.setFont (new Font ("Serif", Font.BOLD, 16));
    countDisplay.setForeground (Color.RED);
    sumDisplay.setForeground (Color.RED);
    maxDisplay.setForeground (Color.RED);
    averageDisplay.setForeground (Color.RED);
    setLayout (new GridLayout (6, 2, 3, 3));
    add (new JLabel ("Car Name", JLabel.RIGHT));
    add (input);
    add (new JLabel ("Car Price ", JLabel.RIGHT));
    add (input2);
    add (new JLabel ("Repair Cost ", JLabel.RIGHT));
    add (input3);
    add (new JLabel ("Tax: ", JLabel.RIGHT));
    add (averageDisplay);
    add (new JLabel ("Total Cost: ", JLabel.RIGHT));
    add (maxDisplay);
    add (resetButton);
    add (computeButton);
    setBorder (BorderFactory.createCompoundBorder (
                BorderFactory.createLineBorder (Color.BLACK, 2),
                BorderFactory.createEmptyBorder (6, 6, 6, 6)
                ));
}






public void actionPerformed (ActionEvent evt)
{
    if (evt.getSource () == resetButton)
        reset ();
    else
        updateStats ();
    input.selectAll ();
    input.requestFocus ();
}



public static void main (String[] args)
{
    JFrame window = new JFrame ("Mike's Car Comparision");
    window.setContentPane (new Chapter4Summ ());
    window.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
    window.pack ();
    window.setLocation (250, 100);
    window.setVisible (true);

}
}

Answer 1

使用JOptionPane的方法，例如showInputDialog。

String someData = JOptionPane.showInputDialog(null, "Input some data");

如果您将关闭打开的对话框，

someData将 null 。

Answer 2

选项＃1

使用不同的外行管理器，可以更好地控制组件的位置，可能类似于GridBagLayout

有关详细信息，请参阅Laying Out Components Within a Container

选项＃2

将“输入字段”放入自定义组件（基于JPanel之类的内容）并将此组件添加到布局中，也可以使用选项＃1 ...

选项＃3

使用JTable

有关详细信息，请参阅How to Use Tables

我似乎无法在不破坏功能的情况下为此程序添加任何JLabel

2 个答案:

选项＃1

选项＃2

选项＃3