在过去的几周里，我花了一些时间在一个小型Java项目的出生日期选择器上。我有一切正常，但似乎有一个错误。当我选择一些日期然后切换JComboBoxes去同步并且不会自动更改其他JComboBox中的选定值，直到按下按钮由于某种原因。我认为这与我的JComboBoxes具有不同大小的索引这一事实有关。
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.text.SimpleDateFormat;
import javax.swing.event.*;
public class dateTest extends JFrame implements ActionListener,ItemListener{
JFrame myMainWindow = new JFrame("This is my title");
JTabbedPane myTabs = new JTabbedPane();
JPanel firstPanel = new JPanel(); //a panel for first tab
//first panel components
String Day2_tmp[]={"1","2","3","4","5","6","7","8","9","10","11","12","13","14","15","16","17","18","19","20","21","22","23","24","25","26","27","28","29","30"};
JComboBox Day2 = new JComboBox(Day2_tmp);
String Day3_tmp[]={"1","2","3","4","5","6","7","8","9","10","11","12","13","14","15","16","17","18","19","20","21","22","23","24","25","26","27","28","29","30","31"};
JComboBox Day3 = new JComboBox(Day3_tmp);
String Month_tmp[]={"January","February","March","April","May","June","July","August","September","October","November","December"};
JComboBox Month = new JComboBox(Month_tmp);
String Day4_tmp[]={"1","2","3","4","5","6","7","8","9","10","11","12","13","14","15","16","17","18","19","20","21","22","23","24","25","26","27","28","29"};
JComboBox Day4 = new JComboBox(Day4_tmp);
Calendar cal = Calendar.getInstance();
JComboBox Y;
JComboBox X;
JButton btnBornOn = new JButton();
Object dd;
Object mm;
Object yyyy;
//end first panel
JLabel tst = new JLabel();
public void runGUI(){
myMainWindow.setBounds(500, 10, 430, 230); //set position, then dimensions
myMainWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myMainWindow.setLayout(new GridLayout(1,1));
createFirstPanel(); //call method to create each panel
setupYears();
myTabs.addTab("First Panel", firstPanel); //add panel //title, image?, panel, tooltip?
myMainWindow.getContentPane().add(firstPanel); //adds the tabbedpane to mainWindow
myMainWindow.setVisible(true); //make the GUI appear
}
public void createFirstPanel(){
firstPanel.setLayout(null);
firstPanel.setBackground( new Color(-1) );
Day2.setLocation(20,50);
Day2.setSize(100,25);
Day2.setVisible(false);
Day2.setEditable(false );
Day2.addItemListener(this);
Day2.addActionListener(this);
Day2.setBackground( new Color(-1) );
firstPanel.add(Day2);
Day3.setLocation(20,50);
Day3.setSize(100,25);
Day3.setVisible(true);
Day3.setEditable(false );
Day3.addItemListener(this);
Day3.addActionListener(this);
Day3.setBackground( new Color(-1) );
firstPanel.add(Day3);
Day4.setLocation(20,50);
Day4.setSize(100,25);
Day4.setVisible(false);
Day4.setEditable(false );
Day4.addItemListener(this);
Day4.addActionListener(this);
Day4.setBackground( new Color(-1) );
firstPanel.add(Day4);
Month.setLocation(160,50);
Month.setSize(100,25);
Month.setEditable(false );
Month.addItemListener(this);
Month.setVisible(true);
Month.setBackground( new Color(-1) );
firstPanel.add(Month);
btnBornOn.setLocation(250,100);
btnBornOn.setSize(150,50);
btnBornOn.setText("DOB DD/MM/YYYY");
btnBornOn.addActionListener(this);
btnBornOn.setOpaque(true);
btnBornOn.setContentAreaFilled(true);
btnBornOn.setBorderPainted(false);
btnBornOn.setVisible(true);
firstPanel.add(btnBornOn);
}
public void setupYears(){
ArrayList<String> years_tmp = new ArrayList<String>();
for(int years = Calendar.getInstance().get(Calendar.YEAR) ; years>=Calendar.getInstance().get(Calendar.YEAR)-90;years--){
if(years % 4 == 0){
years_tmp.add(years+"");
}
}
Y = new JComboBox(years_tmp.toArray());
Y.setLocation(300,50);
Y.setSize(100,25);
Y.setEditable(false );
Y.setVisible(false);
Y.addItemListener(this);
Y.setBackground( new Color(-1) );
firstPanel.add(Y);
ArrayList<String> years2_tmp = new ArrayList<String>();
for(int years2 = Calendar.getInstance().get(Calendar.YEAR) ; years2>=Calendar.getInstance().get(Calendar.YEAR)-90;years2--){
years2_tmp.add(years2+"");
}
X = new JComboBox(years2_tmp.toArray());
X.setLocation(300,50);
X.setSize(100,25);
X.setEditable(false );
X.addItemListener(this);
X.setBackground( new Color(-1) );
firstPanel.add(X);
}
public void setDateInBoxes(){
if(Day2.isVisible()== true){
Day3.setSelectedItem(Day2.getSelectedItem());
Day4.setSelectedItem(Day2.getSelectedItem());
}
if(Day3.isVisible()== true){
Day2.setSelectedItem(Day3.getSelectedItem());
Day4.setSelectedItem(Day3.getSelectedItem());
}
if(Day4.isVisible()== true){
Day3.setSelectedItem(Day4.getSelectedItem());
Day2.setSelectedItem(Day4.getSelectedItem());
}
if(X.isVisible()== true){
Y.setSelectedItem(X.getSelectedItem());
}
if(Y.isVisible()== true){
X.setSelectedItem(Y.getSelectedItem());
}
}
public void actionPerformed(ActionEvent e){
setDateInBoxes();
if(e.getSource() == btnBornOn){
dd =Day3.getSelectedItem();
mm =Month.getSelectedItem();
yyyy =X.getSelectedItem();
System.out.println("This person was born on: "+dd+"/"+mm+"/"+yyyy);
}
}
public void itemStateChanged(ItemEvent e){
if(Month.getSelectedItem().equals("February")){
Day2.setVisible(false);
Day3.setVisible(false);
Day4.setVisible(true);
}
if(Month.getSelectedItem().equals("April")){
Day2.setVisible(true);
Day3.setVisible(false);
Day4.setVisible(false);
}
if(Month.getSelectedItem().equals("June")){
Day2.setVisible(true);
Day3.setVisible(false);
Day4.setVisible(false);
}
if(Month.getSelectedItem().equals("September")){
Day2.setVisible(true);
Day3.setVisible(false);
Day4.setVisible(false);
}
if(Month.getSelectedItem().equals("November")){
Day2.setVisible(true);
Day3.setVisible(false);
Day4.setVisible(false);
}
if(Month.getSelectedItem().equals("January")){
Day2.setVisible(false);
Day3.setVisible(true);
Day4.setVisible(false);
}
if(Month.getSelectedItem().equals("March")){
Day2.setVisible(false);
Day3.setVisible(true);
Day4.setVisible(false);
}
if(Month.getSelectedItem().equals("May")){
Day2.setVisible(false);
Day3.setVisible(true);
Day4.setVisible(false);
}
if(Month.getSelectedItem().equals("July")){
Day2.setVisible(false);
Day3.setVisible(true);
Day4.setVisible(false);
}
if(Month.getSelectedItem().equals("August")){
Day2.setVisible(false);
Day3.setVisible(true);
Day4.setVisible(false);
}
if(Month.getSelectedItem().equals("October")){
Day2.setVisible(false);
Day3.setVisible(true);
Day4.setVisible(false);
}
if(Month.getSelectedItem().equals("December")){
Day2.setVisible(false);
Day3.setVisible(true);
Day4.setVisible(false);
}
if(Day4.getSelectedItem().equals("29")){
Y.setVisible(true);
X.setVisible(false);
}else {
Y.setVisible(false);
X.setVisible(true);
}
if(Day2.isVisible()== true){
Y.setVisible(false);
X.setVisible(true);
}
if(Day3.isVisible()== true){
Y.setVisible(false);
X.setVisible(true);
}
}
public static void main(String[] args){
dateTest gt = new dateTest();
gt.runGUI();
}
}
我希望有人能告诉我问题是什么以及如何解决问题。此外，任何改进建议都会受到欢迎，也会受到批评。另外我很抱歉我输入了大量的代码，但我不知道问题在哪里，所以我不知道要放下什么部分。