我有很多问题与这个应用程序。我一整天都在想这件事，还是想不明白。我有一个用于类的Java应用程序。我所遇到的问题是试图将JRadioButtons分配给数组中的变量，然后将它们传递到公式中。如果有人能帮忙，我会非常感激。
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);
}
}
喂，我用一个例子来说明我上次评论的意思:
我自己，我将创建一个JRadioButtons数组作为我使用的每个组的类字段，并为每个JRadioButtons集群创建一个ButtonGroup对象。然后在我的计算JButton的ActionListener中，我将通过循环通过单选按钮数组或从ButtonGroups getSelection方法获得选中的单选按钮(注意，虽然这返回一个ButtonModel对象或null，如果没有选择)。
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，都不要试图将这些代码复制粘贴到您的程序中，因为它根本不会这样工作(故意的)。这篇文章只是为了说明我上面讨论的概念。
我将扩展JRadioButton以创建一个能够容纳所需变量的类。您可以将其作为内部类来实现，以使事情保持简单。
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:还没到打捞的时候。我按照Eels的建议合并了ButtonGroup，并使它的GUI部分工作(尽管你必须修复布局)，并标记了你需要整理计算的地方。
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);
}
}