double myintc;
double myint1;
double calW;
final JTextField WeightField = new JTextField();
WeightField.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
//String s = WeightField.getText();
myintc = Double.parseDouble(WeightField.getText());
calW = myintc*1.5;
calA =myint1*2.2;
final JButton button = new JButton("Continue");
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// Proceeding to Payment Interface when we Click Continue Buttom
ChickenPay window = new ChickenPay();
window.frmChickenPurchase.setVisible(true);
frmChicjenPurchase.setVisible(false);
JOptionPane.showMessageDialog(button, "Abbattoir is equal to "+ calW);
用户输入号码后。获得calW它总是输出0 myintc也说空了
myintc = Double.parseDouble(WeightField.getText());
我尝试了calW= Double.parseDouble(WeightField.getText()) *1.5;
我仍然得到错误。请帮忙
http://i.stack.imgur.com/14ul2.png
这是整个代码
package pos;
import java.awt.EventQueue;
import pos.ChickenPay;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import java.awt.BorderLayout;
import javax.swing.JOptionPane;
import javax.swing.JTextField;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.BoxLayout;
import java.awt.GridBagLayout;
import java.awt.GridBagConstraints;
import java.awt.Insets;
import java.awt.Window;
import java.awt.Choice;
import javax.swing.JFormattedTextField;
import javax.swing.JCheckBox;
import java.awt.Color;
import java.awt.Font;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.awt.event.ItemListener;
import java.awt.event.ItemEvent;
import java.awt.TextField;
public class ChickenSales {
JFrame frmChicjenPurchase;
private JTextField textField;
public static int ws;
public static int ab;
public double myintc;
double myint1;
public static double calW;
public static double calA;
int tPrice;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
ChickenSales window = new ChickenSales();
window.frmChicjenPurchase.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*/
public ChickenSales() {
initialize();
}
/**
* Initialize the contents of the frame.
*/
private void initialize() {
frmChicjenPurchase = new JFrame();
frmChicjenPurchase.setTitle("Chicken Purchase");
frmChicjenPurchase.setSize(400, 300);
frmChicjenPurchase.setLocationRelativeTo(null);
frmChicjenPurchase.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
GridBagLayout gridBagLayout = new GridBagLayout();
gridBagLayout.columnWidths = new int[]{0, 0, 0, 0, 0, 0, 0, 0, 0};
gridBagLayout.rowHeights = new int[]{55, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
gridBagLayout.columnWeights = new double[]{1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0, Double.MIN_VALUE};
gridBagLayout.rowWeights = new double[]{0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0, Double.MIN_VALUE};
frmChicjenPurchase.getContentPane().setLayout(gridBagLayout);
JLabel lblChickenInformation = new JLabel("Chicken Information");
lblChickenInformation.setFont(new Font("Calisto MT", Font.BOLD, 16));
lblChickenInformation.setForeground(new Color(0, 0, 0));
GridBagConstraints gbc_lblChickenInformation = new GridBagConstraints();
gbc_lblChickenInformation.gridwidth = 4;
gbc_lblChickenInformation.insets = new Insets(0, 0, 5, 5);
gbc_lblChickenInformation.gridx = 3;
gbc_lblChickenInformation.gridy = 0;
frmChicjenPurchase.getContentPane().add(lblChickenInformation, gbc_lblChickenInformation);
JLabel lblWeight = new JLabel("Weight (kg)");
GridBagConstraints gbc_lblWeight = new GridBagConstraints();
gbc_lblWeight.gridwidth = 3;
gbc_lblWeight.insets = new Insets(0, 0, 5, 5);
gbc_lblWeight.gridx = 2;
gbc_lblWeight.gridy = 1;
frmChicjenPurchase.getContentPane().add(lblWeight, gbc_lblWeight);
final JTextField WeightField = new JTextField();
WeightField.addActionListener(new ActionListener( ) {
public void actionPerformed(ActionEvent e) {
//String s = WeightField.getText();
// myintc = Double.parseDouble(WeightField.getText());
}
});
WeightField.setColumns(5);
WeightField.setToolTipText("Enter Weight betwwen 2-8 kg");
GridBagConstraints gbc_WeightField = new GridBagConstraints();
gbc_WeightField.anchor = GridBagConstraints.WEST;
gbc_WeightField.insets = new Insets(0, 0, 5, 0);
gbc_WeightField.gridx = 7;
gbc_WeightField.gridy = 1;
frmChicjenPurchase.getContentPane().add(WeightField, gbc_WeightField);
JLabel lblAge = new JLabel("Age");
GridBagConstraints gbc_lblAge = new GridBagConstraints();
gbc_lblAge.insets = new Insets(0, 0, 5, 5);
gbc_lblAge.gridx = 3;
gbc_lblAge.gridy = 3;
frmChicjenPurchase.getContentPane().add(lblAge, gbc_lblAge);
final JFormattedTextField AgeField = new JFormattedTextField();
AgeField.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
//String B = AgeField.getText();
try{
myint1 = Double.parseDouble(AgeField.getText());
if(myint1>=6 && myint1 <=24){
}
}
catch (Exception e1){
System.out.println("Weight ranges between 2-8kg");
}
}
//END AGE HERE
});
AgeField.setToolTipText("Enter Age betwwen 6-24 months");
AgeField.setColumns(5);
GridBagConstraints gbc_AgeField = new GridBagConstraints();
gbc_AgeField.anchor = GridBagConstraints.WEST;
gbc_AgeField.insets = new Insets(0, 0, 5, 0);
gbc_AgeField.gridx = 7;
gbc_AgeField.gridy = 3;
frmChicjenPurchase.getContentPane().add(AgeField, gbc_AgeField);
JLabel lblBreed = new JLabel("Breed");
GridBagConstraints gbc_lblBreed = new GridBagConstraints();
gbc_lblBreed.insets = new Insets(0, 0, 5, 5);
gbc_lblBreed.gridx = 3;
gbc_lblBreed.gridy = 5;
frmChicjenPurchase.getContentPane().add(lblBreed, gbc_lblBreed);
// ACTION LISTENER 4 BREED
final Choice BreedChoice = new Choice();
BreedChoice.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
String wa = BreedChoice.getSelectedItem();
switch (wa){
case "W":
ws =100;
break;
case "X":
ws =150;
break;
case "Y":
ws =200;
break;
case "Z":
ws =350;
break;
default:
}
}
});
BreedChoice.add("--");
BreedChoice.add("W");
BreedChoice.add("X");
BreedChoice.add("Y");
BreedChoice.add("Z");
GridBagConstraints gbc_BreedChoice = new GridBagConstraints();
gbc_BreedChoice.insets = new Insets(0, 0, 5, 0);
gbc_BreedChoice.anchor = GridBagConstraints.WEST;
gbc_BreedChoice.gridx = 7;
gbc_BreedChoice.gridy = 5;
frmChicjenPurchase.getContentPane().add(BreedChoice, gbc_BreedChoice);
JLabel lblAbattoir = new JLabel("Abattoir Service");
GridBagConstraints gbc_lblAbattoir = new GridBagConstraints();
gbc_lblAbattoir.insets = new Insets(0, 0, 5, 5);
gbc_lblAbattoir.gridx = 3;
gbc_lblAbattoir.gridy = 7;
frmChicjenPurchase.getContentPane().add(lblAbattoir, gbc_lblAbattoir);
final JCheckBox abbattoirCheckBox = new JCheckBox("");
abbattoirCheckBox.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
boolean selected = abbattoirCheckBox.getModel().isSelected();
if (selected){
ab =50;
}
}
});
//LOGIC STARTS HERE
calW = myintc*1.5;
calA =myint1*2.2;
//---------------
abbattoirCheckBox.setToolTipText("Costs N50");
GridBagConstraints gbc_abbattoirCheckBox = new GridBagConstraints();
gbc_abbattoirCheckBox.insets = new Insets(0, 0, 5, 0);
gbc_abbattoirCheckBox.anchor = GridBagConstraints.WEST;
gbc_abbattoirCheckBox.gridx = 7;
gbc_abbattoirCheckBox.gridy = 7;
frmChicjenPurchase.getContentPane().add(abbattoirCheckBox, gbc_abbattoirCheckBox);
final JButton button = new JButton("Continue");
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// Proceeding to Payment Interface when we Click Continue Buttom
ChickenPay window = new ChickenPay();
window.frmChickenPurchase.setVisible(true);
frmChicjenPurchase.setVisible(false);
JOptionPane.showMessageDialog(button, "Abbattoir is equal to "+ calW);
}
});
GridBagConstraints gbc_button = new GridBagConstraints();
gbc_button.anchor = GridBagConstraints.ABOVE_BASELINE;
gbc_button.insets = new Insets(0, 0, 5, 5);
gbc_button.gridx = 5;
gbc_button.gridy = 8;
frmChicjenPurchase.getContentPane().add(button, gbc_button);
JPanel marginPanel = new JPanel();
marginPanel.setBounds(5, 5, 5, 5);
GridBagConstraints gbc_marginPanel = new GridBagConstraints();
gbc_marginPanel.insets = new Insets(0, 0, 0, 5);
gbc_marginPanel.fill = GridBagConstraints.BOTH;
gbc_marginPanel.gridx = 0;
gbc_marginPanel.gridy = 9;
frmChicjenPurchase.getContentPane().add(marginPanel, gbc_marginPanel);
}
}
答案 0 :(得分：1)
仅在焦点位于JTextField时按下Enter时才会调用JTextField的动作侦听器。如果用户在字段中键入数字，然后选中标签或单击按钮，则不会调用操作侦听器，因此您的变量myintc将保持未初始化状态。
应将JTextField的解析移动到按钮的动作侦听器中，以确保在按下“继续”按钮时执行该操作。
例如）
final JTextField WeightField = new JTextField();
// (no action listener required here)
final JButton button = new JButton("Continue");
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
myintc = Double.parseDouble(WeightField.getText());
calW = myintc*1.5;
// Remainder of "Proceeding to Payment" code
}
});
答案 1 :(得分：1)
用户输入号码后。为了获得calW，它总是输出0，myintc也称为null
calW始终为零，因为在您的整个代码中，您根本没有更改其值。
您为其分配值的唯一位置是initialize()方法。但是，您将其指定为：
calW = myintc*1.5; //myintc is 0!
myintc根本未初始化，因此会为其分配默认0值，导致calW也被初始化为0。
由于calW已初始化为零且此变量没有进一步更新，因此0始终会获得calW。
一些建议：
您正在创建太多静态变量，并且您的实现代码被抛入一个巨大的类中。对于像这样的程序，您不需要静态变量。相反，您可以创建自定义容器类，例如具有所需组件的自定义JPanel。这样，您的类就是自包含的，并且更容易阅读和维护。
将变量声明为适当的范围，并使用getter和setter访问它们。