plMortgage Calculator GUI 存在很多问题

Question

我对这个应用程序有很多问题。我一整天都在做这件事，但无法弄清楚这一点。我有一个用于类的 Java 应用程序。我遇到的问题是尝试将 JRadioButtons 分配给数组中的变量，然后将它们传递到公式中。如果有人可以提供帮助，我将非常感激。

import java.awt.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.text.NumberFormat;

import javax.swing.*;
import javax.swing.border.*;
import javax.swing.JRadioButton;

public class MortgageCalculatorGUI8 extends JFrame {

    JPanel panel1 = new JPanel();

    double Principal;
    double [] Interest = {5.35, 5.5, 5.75};
    double temp_Interest;
    int [] Length = {7, 15, 30};
    int temp_Length;
    boolean ok = false;


    public MortgageCalculatorGUI8(){

        getContentPane ().setLayout (null);
        setSize (400,400);

        panel1.setLayout (null);
        panel1.setBounds (0, 0, 2000, 800);
        add (panel1);

        JLabel mortgageLabel = new JLabel("Mortgage Amount $", JLabel.LEFT);
        mortgageLabel.setBounds (15, 15, 150, 30);
        panel1.add (mortgageLabel);

        final JTextField mortgageText = new JTextField(10);
        mortgageText.setBounds (130, 15, 150, 30);
        panel1.add (mortgageText);

        JLabel termLabel = new JLabel("Mortgage Term (Years)", JLabel.LEFT);
        termLabel.setBounds (340, 40, 150, 30);
        panel1.add (termLabel);

        JTextField termText = new JTextField(3);
        termText.setBounds (340, 70, 150, 30);
        panel1.add (termText);

        JLabel intRateLabel = new JLabel("Interest Rate (%)", JLabel.LEFT);
        intRateLabel.setBounds (340, 94, 150, 30);
        panel1.add (intRateLabel);

        JTextField intRateText = new JTextField(5);
        intRateText.setBounds (340, 120, 150, 30);
        panel1.add (intRateText);

        JLabel mPaymentLabel = new JLabel("Monthly Payment $", JLabel.LEFT);
        mPaymentLabel.setBounds (550, 40, 150, 30);
        panel1.add (mPaymentLabel);

        JTextField mPaymentText = new JTextField(10);
        mPaymentText.setBounds (550, 70, 150, 30);
        panel1.add (mPaymentText);

//      JLabel paymentLabel = new JLabel ("Payment #");
//      JLabel balLabel = new JLabel (" Balance");
//      JLabel ytdPrincLabel = new JLabel (" Principal");
//      JLabel ytdIntLabel = new JLabel (" Interest");

        JTextArea textArea = new JTextArea(10, 31);
        textArea.setBounds (550, 100, 150, 30);
        panel1.add (textArea);
        JScrollPane scroll = new JScrollPane(textArea, JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
        scroll.setBounds (450, 200, 300, 150);
        panel1.add (scroll);


    public void rbuttons(){

        JLabel tYears = new JLabel("Years of Loan Amount");
        tYears.setBounds (30, 35, 150, 30);
        panel1.add (tYears);
        JRadioButton b7Yr = new JRadioButton("7 Years",false);
        b7Yr.setBounds (30, 58, 150, 30);
        panel1.add (b7Yr);
        JRadioButton b15Yr = new JRadioButton("15 Years",false);
        b15Yr.setBounds (30, 80, 150, 30);
        panel1.add (b15Yr);
        JRadioButton b30Yr = new JRadioButton("30 Years",false);
        b30Yr.setBounds (30, 101, 150, 30);
        panel1.add (b30Yr);


        JLabel tInterest = new JLabel("Interest Rate Of the Loan");
        tInterest.setBounds (175, 35, 150, 30);
        panel1.add(tInterest);
        JRadioButton b535Int = new JRadioButton("5.35% Interest",false);
        b535Int.setBounds (178, 58, 150, 30);
        panel1.add (b535Int);
        JRadioButton b55Int = new JRadioButton("5.5% Interest",false);
        b55Int.setBounds (178, 80, 150, 30);
        panel1.add (b55Int);
        JRadioButton b575Int = new JRadioButton("5.75% Interest",false);
        b575Int.setBounds (178, 101, 150, 30);
        panel1.add (b575Int);
    }

        JButton calculateButton = new JButton("CALCULATE");
        calculateButton.setBounds (30, 400, 120, 30);
        panel1.add (calculateButton);

        calculateButton.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e)
            {


                    if(e.getSource () == b7Yr){
                        b7Yr = Length[0];
                    }
                    if(e.getSource () == b15Yr){
                        b15Yr = Length[1];
                    }
                    if(e.getSource () == b30Yr){
                        b30Yr = Length[2];
                    }
                    if(e.getSource () == b535Int){
                        b535Int = Interest[0];
                    }
                    if(e.getSource () == b55Int){
                        b55Int = Interest[1];
                    }
                    if(e.getSource () == b575Int){
                        b575Int = Interest[2];
                    }


                double Principal;
//              double [] Interest;
//              int [] Length;
                double M_Interest = Interest /(12*100);
                double Months = Length  * 12;

                Principal = Double.parseDouble (mortgageText.getText());

                double M_Payment = Principal * ( M_Interest / (1 - (Math.pow((1 + M_Interest), - Months))));

                NumberFormat Money = NumberFormat.getCurrencyInstance();



            }
            });




        JButton clearButton = new JButton("CLEAR");
        clearButton.setBounds (160, 400, 120, 30);
        panel1.add (clearButton);

        clearButton.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e)
            {
                mortgageText.setText (null);
                b7Yr.setSelected (false);
                b15Yr.setSelected (false);
                b30Yr.setSelected (false);
                b535Int.setSelected (false);
                b55Int.setSelected (false);
                b575Int.setSelected (false);
            }
            });


        JButton exitButton = new JButton("EXIT");
        exitButton.setBounds (290, 400, 120, 30);
        panel1.add (exitButton);

        exitButton.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e)
            {
                System.exit(0);
            }
            });


    }

    public static void main(String[] args) {

        MortgageCalculatorGUI8 frame = new MortgageCalculatorGUI8();
        frame.setBounds (400, 200, 800, 800);
        frame.setTitle ("Mortgage Calculator 1.0.4");
        frame.setDefaultCloseOperation (EXIT_ON_CLOSE);
        frame.setVisible (true);



    }
}

Answer 1

好吧，我将通过一个例子向您展示我在上一条评论中的意思：

我自己，我会为我使用的每个组创建一个 JRadioButton 数组作为类字段，并为每个 JRadioButton 集群创建一个 ButtonGroup 对象。然后，在我的计算 JButton 的 ActionListener 中，我将通过循环单选按钮数组或从 ButtonGroups getSelection 方法获取选定的单选按钮（请注意，这将返回 ButtonModel 对象，如果未选择任何内容，则返回 null）。

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

public class InfoFromRadioBtns extends JPanel {
   private static final long serialVersionUID = 1L;
   private int[] foobars = {1, 2, 5, 10, 20};
   private JRadioButton[] foobarRButtons = new JRadioButton[foobars.length];
   private ButtonGroup foobarBtnGroup = new ButtonGroup();

   public InfoFromRadioBtns() {
      // jpanel to hold one set of radio buttons
      JPanel radioBtnPanel = new JPanel(new GridLayout(0, 1));
      radioBtnPanel.setBorder(BorderFactory
               .createTitledBorder("Choose a Foobar"));

      // iterate through the radio button array creating buttons
      // and adding them to the radioBtnPanel and the
      // foobarBtnGroup ButtonGroup
      for (int i = 0; i < foobarRButtons.length; i++) {
         // string for radiobutton to dislay -- just the number
         String buttonText = String.valueOf(foobars[i]);
         JRadioButton radiobtn = new JRadioButton("foobar " + buttonText);
         radiobtn.setActionCommand(buttonText); // one way to find out which
                                                // button is selected
         radioBtnPanel.add(radiobtn); // add radiobutton to its panel
         foobarBtnGroup.add(radiobtn); // add radiobutton to its button group

         // add to array
         foobarRButtons[i] = radiobtn;
      }

      // one way to get the selected JRadioButton
      JButton getRadioChoice1 = new JButton("Get Radio Choice 1");
      getRadioChoice1.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
            ButtonModel seletedModel = foobarBtnGroup.getSelection();
            if (seletedModel != null) {
               String actionCommand = seletedModel.getActionCommand();
               System.out.println("selected foobar: " + actionCommand);
            } else {
               System.out.println("No foobar selected");
            }
         }
      });

      // another way to get the selected JRadioButton
      JButton getRadioChoice2 = new JButton("Get Radio Choice 2");
      getRadioChoice2.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
            String actionCommand = "";
            for (JRadioButton foobarRButton : foobarRButtons) {
               if (foobarRButton.isSelected()) {
                  actionCommand = foobarRButton.getActionCommand();
               }
            }
            if (actionCommand.isEmpty()) {
               System.out.println("No foobar selected");
            } else {
               System.out.println("selected foobar: " + actionCommand);
            }

         }
      });

      JPanel jBtnPanel = new JPanel();
      jBtnPanel.add(getRadioChoice1);
      jBtnPanel.add(getRadioChoice2);

      // make main GUI use a BordeLayout
      setLayout(new BorderLayout());
      add(radioBtnPanel, BorderLayout.CENTER);
      add(jBtnPanel, BorderLayout.PAGE_END);
   }

   private static void createAndShowUI() {
      JFrame frame = new JFrame("InfoFromRadioBtns");
      frame.getContentPane().add(new InfoFromRadioBtns());
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.pack();
      frame.setLocationRelativeTo(null);
      frame.setVisible(true);
   }

   public static void main(String[] args) {
      java.awt.EventQueue.invokeLater(new Runnable() {
         public void run() {
            createAndShowUI();
         }
      });
   }
}

无论您做什么，都不要尝试将任何代码复制并粘贴到您的程序中，因为它根本不会以这种方式工作（故意）。发布它只是为了说明我上面讨论的概念。

Answer 2

我将扩展 JRadioButton 以创建一个能够保存所需变量的类。您可以将其作为内部类来执行，以使事情变得简单。

private double pctinterest;
private int numyears; // within scope of your containing class

private class RadioButtonWithYears extends JRadioButton {
    final private int years;
    private int getYears() { return years; }
    public RadioButtonWithYears(int years) {
        super(years + " years",false);
        this.years = years;
        addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                numyears = getYears();
            }
        });
    }
}

// elsewhere
RadioButtonWithYears b7Yr = new RadioButtonWithYears(7);
RadioButtonWithYears b15Yr = new RadioButtonWithYears(15);
RadioButtonWithYears b30Yr = new RadioButtonWithYears(30);

// then later
double M_Interest = java.lang.Math.pow((pctinternet / 100)+1, numyears);

更新：它还没有到挽救的地步。我已经按照 Eels 的建议合并了 ButtonGroup，并使 GUI 部分工作（尽管您必须修复布局）并标记了需要整理计算的位置。

package stack.swing;

import java.awt.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.math.BigDecimal;
import java.text.NumberFormat;

import javax.swing.*;
import javax.swing.border.*;
import javax.swing.JRadioButton;

public class MortgageCalculatorGUI8 extends JFrame {

    JPanel panel1 = new JPanel();

    Integer Principal;
    boolean ok = false;

    private BigDecimal temp_Interest;
    private int temp_Length; // within scope of your containing class

    private class JRadioButtonWithYears extends JRadioButton {
        final private int years;
        private int getYears() { return years; }
        public JRadioButtonWithYears(int years) {
            super(years + " years",false);
            this.years = years;
            addActionListener(new ActionListener() {
                public void actionPerformed(ActionEvent e) {
                    temp_Length = getYears();
                }
            });
        }
    }

    private class JRadioButtonWithPct extends JRadioButton {
        final private BigDecimal pct;
        private BigDecimal getPct() { return pct; }
        public JRadioButtonWithPct(String pct) {
            super(pct + "%",false);
            this.pct = new BigDecimal(pct);
            addActionListener(new ActionListener() {
                public void actionPerformed(ActionEvent e) {
                    temp_Interest = getPct();
                }
            });
        }
    }

    public MortgageCalculatorGUI8() {

        getContentPane ().setLayout (null);
        setSize (400,400);

        panel1.setLayout (null);
        panel1.setBounds (0, 0, 2000, 800);
        add (panel1);

        JLabel mortgageLabel = new JLabel("Mortgage Amount $", JLabel.LEFT);
        mortgageLabel.setBounds (15, 15, 150, 30);
        panel1.add (mortgageLabel);

        final JTextField mortgageText = new JTextField(10);
        mortgageText.setBounds (130, 15, 150, 30);
        panel1.add (mortgageText);

        JLabel termLabel = new JLabel("Mortgage Term (Years)", JLabel.LEFT);
        termLabel.setBounds (340, 40, 150, 30);
        panel1.add (termLabel);

        JTextField termText = new JTextField(3);
        termText.setBounds (340, 70, 150, 30);
        panel1.add (termText);

        JLabel intRateLabel = new JLabel("Interest Rate (%)", JLabel.LEFT);
        intRateLabel.setBounds (340, 94, 150, 30);
        panel1.add (intRateLabel);

        JTextField intRateText = new JTextField(5);
        intRateText.setBounds (340, 120, 150, 30);
        panel1.add (intRateText);

        JLabel mPaymentLabel = new JLabel("Monthly Payment $", JLabel.LEFT);
        mPaymentLabel.setBounds (550, 40, 150, 30);
        panel1.add (mPaymentLabel);

        JTextField mPaymentText = new JTextField(10);
        mPaymentText.setBounds (550, 70, 150, 30);
        panel1.add (mPaymentText);

//      JLabel paymentLabel = new JLabel ("Payment #");
//      JLabel balLabel = new JLabel (" Balance");
//      JLabel ytdPrincLabel = new JLabel (" Principal");
//      JLabel ytdIntLabel = new JLabel (" Interest");

        JTextArea textArea = new JTextArea(10, 31);
        textArea.setBounds (550, 100, 150, 30);
        panel1.add (textArea);
        JScrollPane scroll = new JScrollPane(textArea, JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
        scroll.setBounds (450, 200, 300, 150);
        panel1.add (scroll);

        // jpanel to hold one set of radio buttons
        JPanel yearsPanel = new JPanel(new GridLayout(0, 1));
        yearsPanel.setBorder(BorderFactory
                 .createTitledBorder("Years of Loan Amount"));
        yearsPanel.setBounds(30, 55, 150, 150);
        panel1.add (yearsPanel);
        final ButtonGroup yearsGroup = new ButtonGroup();

        int years[] = { 7, 15, 30 };
        for (int i = 0; i < years.length; i++) {
           JRadioButtonWithYears radiobtn = new JRadioButtonWithYears(years[i]);
           yearsPanel.add(radiobtn); // add radiobutton to its panel
           yearsGroup.add(radiobtn); // add radiobutton to its button group
        }

        // jpanel to hold one set of radio buttons
        JPanel pctPanel = new JPanel(new GridLayout(0, 1));
        pctPanel.setBorder(BorderFactory
                 .createTitledBorder("Interest Rate Of the Loan"));
        pctPanel.setBounds(175, 55, 180, 150);
        panel1.add (pctPanel);
        final ButtonGroup pctGroup = new ButtonGroup();

        String pct[] = { "5.35", "5.5", "5.75" };
        for (int i = 0; i < pct.length; i++) {
           JRadioButtonWithPct radiobtn = new JRadioButtonWithPct(pct[i]);
           pctPanel.add(radiobtn); // add radiobutton to its panel
           pctGroup.add(radiobtn); // add radiobutton to its button group
        }

        final JButton calculateButton = new JButton("CALCULATE");
        calculateButton.setBounds (30, 400, 120, 30);
        panel1.add (calculateButton);

        calculateButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                double M_Interest = temp_Interest.doubleValue() /(12*100);
                double Months = temp_Length  * 12;

                Principal = Integer.parseInt(mortgageText.getText());

                double M_Payment = Principal * ( M_Interest / (1 - (Math.pow((1 + M_Interest), - Months))));

                NumberFormat Money = NumberFormat.getCurrencyInstance();

                /** MORE STUFF TO HAPPEN HERE */
            }
            });

        JButton clearButton = new JButton("CLEAR");
        clearButton.setBounds (160, 400, 120, 30);
        panel1.add (clearButton);

        clearButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                mortgageText.setText (null);
                yearsGroup.clearSelection();
                pctGroup.clearSelection();
            }
            });

        JButton exitButton = new JButton("EXIT");
        exitButton.setBounds (290, 400, 120, 30);
        panel1.add (exitButton);

        exitButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                System.exit(0);
            }
            });
    }

    public static void main(String[] args) {
        MortgageCalculatorGUI8 frame = new MortgageCalculatorGUI8();
        frame.setBounds (400, 200, 800, 800);
        frame.setTitle ("Mortgage Calculator 1.0.4");
        frame.setDefaultCloseOperation (EXIT_ON_CLOSE);
        frame.setVisible (true);
    }
}