如何通过简单的SWING日历BEAN开发学习Calendar类？

在上一节，我们讨论了Calendar的基本概况，而本节我们将使用java.util包自带的GregorianCalendar——一个真正可以实例化的标准日历类，来建立一个名为JCalendar的GUI日历。如下图：

先把JCalendar的源代码放上来，而分析我们将在下一节进行。各位也可以通过代码中的注释先行了解一下大概的情况。

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.SystemColor;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.awt.event.MouseEvent;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.Locale;
import java.util.Date;
import java.util.StringTokenizer;

import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.JToggleButton;
import javax.swing.SwingConstants;
import javax.swing.UIManager;

/**
* <p>Title: Swing日历</p>
* <p>Description: 操作日期</p>
* @author duxu2004
* @version 1.0.1
*/

public class JCalendar extends JPanel{
//动态表示年月日
private int year=0;
private int month=0;
private int day=0;
//主面板
private JPanel Main = new JPanel();
//日面板
private JPanel jPanelDay = new JPanel();
//月面板
private JPanel jPanelMonth = new JPanel();
//年的输入位置
private JTextField Year = new JTextField();
//月的输入位置
private JTextField Month = new JTextField();
//减少月份
private JButton MonthDown = new JButton();
//增加月份
private JButton MonthUp = new JButton();

private JPanel jPanelButton = new JPanel();
//减少年份
private JButton YearDown = new JButton();
//增加年份
private JButton YearUp = new JButton();
//显示日期的位置
private JLabel Out = new JLabel();
//中国时区，以后可以从这里扩展可以设置时区的功能
private Locale l=Locale.CHINESE;
//主日历
private GregorianCalendar cal=new GregorianCalendar(l);
//星期面板
private JPanel weekPanel=new JPanel();
//天按钮组
private JToggleButton[] days=new JToggleButton[42];
//天面板
private JPanel Days = new JPanel();
//标示
private JLabel jLabel1 = new JLabel();
private JLabel jLabel2 = new JLabel();
private JLabel jLabel3 = new JLabel();
private JLabel jLabel4 = new JLabel();
private JLabel jLabel5 = new JLabel();
private JLabel jLabel6 = new JLabel();
private JLabel jLabel7 = new JLabel();
//当前选择的天数按钮
private JToggleButton cur=null;
//月份天数数组，用来取得当月有多少天
// 1 2 3 4 5 6 7 8 9 10 11 12
private int[] mm={31,28,31,30,31,30,31,31,30,31,30,31};

//空日期构造函数
public JCalendar() {
try {
jbInit();
}
catch(Exception e) {
e.printStackTrace();
}

}
//带日期设置的构造函数
public JCalendar(int year, int month, int day) {
cal.set(year, month, day);
try {
jbInit();
}
catch (Exception e) {
e.printStackTrace();
}
}
//带日历输入的构造函数
public JCalendar(GregorianCalendar calendar) {
cal=calendar;
try {
jbInit();
}
catch (Exception e) {
e.printStackTrace();
}
}
//带日期输入的构造函数
public JCalendar(Date date) {
cal.setTime(date);
try {
jbInit();
}
catch (Exception e) {
e.printStackTrace();
}
}
//初始化组件
private void jbInit() throws Exception {
//初始化年、月、日
iniCalender();

this.setLayout(new BorderLayout());
this.setBorder(BorderFactory.createRaisedBevelBorder());
this.setMaximumSize(new Dimension(200, 200));
this.setMinimumSize(new Dimension(200, 200));
this.setPreferredSize(new Dimension(200, 200));

Main.setLayout(new BorderLayout());
Main.setBackground(SystemColor.info);
Main.setBorder(null);

Out.setBackground(Color.lightGray);
Out.setHorizontalAlignment(SwingConstants.CENTER);
Out.setMaximumSize(new Dimension(100, 19));
Out.setMinimumSize(new Dimension(100, 19));
Out.setPreferredSize(new Dimension(100, 19));

jLabel1.setForeground(Color.red);
jLabel1.setHorizontalAlignment(SwingConstants.CENTER);
jLabel1.setHorizontalTextPosition(SwingConstants.CENTER);
jLabel1.setText("日");
jLabel2.setForeground(Color.blue);
jLabel2.setHorizontalAlignment(SwingConstants.CENTER);
jLabel2.setHorizontalTextPosition(SwingConstants.CENTER);
jLabel2.setText("六");
jLabel3.setHorizontalAlignment(SwingConstants.CENTER);
jLabel3.setHorizontalTextPosition(SwingConstants.CENTER);
jLabel3.setText("五");
jLabel4.setHorizontalAlignment(SwingConstants.CENTER);
jLabel4.setHorizontalTextPosition(SwingConstants.CENTER);
jLabel4.setText("四");
jLabel5.setHorizontalAlignment(SwingConstants.CENTER);
jLabel5.setHorizontalTextPosition(SwingConstants.CENTER);
jLabel5.setText("三");
jLabel6.setBorder(null);
jLabel6.setHorizontalAlignment(SwingConstants.CENTER);
jLabel6.setHorizontalTextPosition(SwingConstants.CENTER);
jLabel6.setText("二");
jLabel7.setBackground(Color.lightGray);
jLabel7.setForeground(Color.black);
jLabel7.setBorder(null);
jLabel7.setHorizontalAlignment(SwingConstants.CENTER);
jLabel7.setHorizontalTextPosition(SwingConstants.CENTER);
jLabel7.setText("一");

weekPanel.setBackground(UIManager.getColor("InternalFrame.activeTitleGradient"));
weekPanel.setBorder(BorderFactory.createEtchedBorder());
weekPanel.setLayout(new GridLayout(1,7));
weekPanel.add(jLabel1, null);
weekPanel.add(jLabel7, null);
weekPanel.add(jLabel6, null);
weekPanel.add(jLabel5, null);
weekPanel.add(jLabel4, null);
weekPanel.add(jLabel3, null);
weekPanel.add(jLabel2, null);

MonthUp.setAlignmentX((float) 0.0);
MonthUp.setActionMap(null);

jPanelMonth.setBackground(SystemColor.info);
jPanelMonth.setLayout(new BorderLayout());
jPanelMonth.setBorder(BorderFactory.createEtchedBorder());


Month.setBorder(null);
Month.setHorizontalAlignment(SwingConstants.CENTER);
Month.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseClicked(MouseEvent e) {
Month_mouseClicked(e);
}
});
Month.addKeyListener(new java.awt.event.KeyAdapter() {
public void keyPressed(KeyEvent e) {
Month_keyPressed(e);
}
});

MonthDown.setBorder(null);
MonthDown.setText("/u25C4");
MonthDown.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(ActionEvent e) {
MonthDown_actionPerformed(e);
}
});
MonthUp.setBorder(null);
MonthUp.setText("/u25BA");
MonthUp.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(ActionEvent e) {
MonthUp_actionPerformed(e);
}
});


jPanelButton.setLayout(null);
jPanelButton.setBorder(null);
jPanelButton.addComponentListener(new java.awt.event.ComponentAdapter() {
public void componentResized(java.awt.event.ComponentEvent evt) {
jPanelButtonComponentResized(evt);
}
});

Year.setBorder(BorderFactory.createEtchedBorder());
Year.setMaximumSize(new Dimension(80, 25));
Year.setMinimumSize(new Dimension(80, 25));
Year.setPreferredSize(new Dimension(80, 25));
Year.setHorizontalAlignment(SwingConstants.CENTER);
Year.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseClicked(MouseEvent e) {
Year_mouseClicked(e);
}
});
Year.addKeyListener(new java.awt.event.KeyAdapter() {
public void keyPressed(KeyEvent e) {
Year_keyPressed(e);
}
});

YearDown.setBorder(null);
YearDown.setMaximumSize(new Dimension(16, 16));
YearDown.setMinimumSize(new Dimension(16, 16));
YearDown.setPreferredSize(new Dimension(16, 16));
YearDown.setSize(new Dimension(16, 16));
YearDown.setText("▼");
YearDown.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(ActionEvent e) {
YearDown_actionPerformed(e);
}
});
YearUp.setBorder(null);
YearUp.setMaximumSize(new Dimension(16, 16));
YearUp.setMinimumSize(new Dimension(16, 16));
YearUp.setPreferredSize(new Dimension(16, 16));
YearUp.setSize(new Dimension(16, 16));
YearUp.setText("▲");
YearUp.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(ActionEvent e) {
YearUp_actionPerformed(e);
}
});

jPanelDay.setLayout(new BorderLayout());

Days.setLayout(new GridLayout(6,7));
Days.setBackground(SystemColor.info);

for(int i=0;i<42;i++){
days[i]=new JToggleButton();
days[i].setBorder(null);
days[i].setBackground(SystemColor.info);
days[i].setHorizontalAlignment(SwingConstants.CENTER);
days[i].setHorizontalTextPosition(SwingConstants.CENTER);
//days[i].setSize(l,l);
days[i].addActionListener(new java.awt.event.ActionListener(){
public void actionPerformed(ActionEvent e) {
day=Integer.parseInt(((JToggleButton)e.getSource()).getText());
showDate();
showDays();
}
});
Days.add(days[i]);
}

this.add(Main, BorderLayout.NORTH);
this.add(jPanelDay, BorderLayout.CENTER);
this.add(jPanelMonth, BorderLayout.SOUTH);

Main.add(Year, BorderLayout.CENTER);
Main.add(Out, BorderLayout.WEST);
Main.add(jPanelButton, BorderLayout.EAST);

jPanelButton.add(YearUp);
jPanelButton.add(YearDown);

jPanelDay.add(weekPanel,BorderLayout.NORTH);
jPanelDay.add(Days, BorderLayout.CENTER);

jPanelMonth.add(Month, BorderLayout.CENTER);
jPanelMonth.add(MonthDown, BorderLayout.WEST);
jPanelMonth.add(MonthUp, BorderLayout.EAST);

showMonth();
showYear();
showDate();
showDays();
}

//自定义重画年选择面板
void jPanelButtonComponentResized(java.awt.event.ComponentEvent evt){
YearUp.setLocation(0,0);
YearDown.setLocation(0,YearUp.getHeight());
jPanelButton.setSize(YearUp.getWidth(),YearUp.getHeight()*2);
jPanelButton.setPreferredSize(new Dimension(YearUp.getWidth(),YearUp.getHeight()*2));
jPanelButton.updateUI();
}

//测试用
public static void main(String[] args){
JFrame f=new JFrame();
f.setContentPane(new JCalendar());
f.pack();
//f.setResizable(false);
f.show();
}

//增加年份
void YearUp_actionPerformed(ActionEvent e) {
year++;
showYear();
showDate();
showDays();
}

//减少年份
void YearDown_actionPerformed(ActionEvent e) {
year--;
showYear();
showDate();
showDays();
}

//减少月份
void MonthDown_actionPerformed(ActionEvent e) {
month--;
if(month<0) {
month = 11;
year--;
showYear();
}
showMonth();
showDate();
showDays();
}

//增加月份
void MonthUp_actionPerformed(ActionEvent e) {
month++;
if(month==12) {
month=0;
year++;
showYear();
}
showMonth();
showDate();
showDays();
}

//初始化年月日
void iniCalender(){
year=cal.get(Calendar.YEAR);
month=cal.get(Calendar.MONTH);
day=cal.get(Calendar.DAY_OF_MONTH);
}

//刷新月份
void showMonth(){
Month.setText(Integer.toString(month+1)+"月");
}

//刷新年份
void showYear(){
Year.setText(Integer.toString(year)+"年");
}

//刷新日期
void showDate(){
Out.setText(Integer.toString(year)+"-"+Integer.toString(month+1)+"-"+Integer.toString(day));
}

//重画天数选择面板
void showDays() {
cal.set(year,month,1);
int firstDayOfWeek = cal.get(Calendar.DAY_OF_WEEK);
int n=mm[month];
if(cal.isLeapYear(year)&&month==1) n++;
int i=0;
for(;i<firstDayOfWeek-1;i++){
days[i].setEnabled(false);
days[i].setSelected(false);
days[i].setText("");
}
int d=1;
for(;d<=n;d++){
days[i].setText(Integer.toString(d));
days[i].setEnabled(true);
if(d==day) days[i].setSelected(true);
else days[i].setSelected(false);;
i++;
}
for(;i<42;i++){
days[i].setEnabled(false);
days[i].setSelected(false);
days[i].setText("");
}
}

//单击年份面板选择整个年份字符串
void SelectionYear(){
Year.setSelectionStart(0);
Year.setSelectionEnd(Year.getText().length());
}

//单击月份面板选择整个月份字符串
void SelectionMonth(){
Month.setSelectionStart(0);
Month.setSelectionEnd(Month.getText().length());
}

//月份面板响应鼠标单击事件
void Month_mouseClicked(MouseEvent e) {
//SelectionMonth();
inputMonth();
}

//检验输入的月份
void inputMonth(){
String s;
if(Month.getText().endsWith("月"))
{
s=Month.getText().substring(0,Month.getText().length()-1);
}
else s=Month.getText();
month=Integer.parseInt(s)-1;
this.showMe();
}

//月份面板键盘敲击事件响应
void Month_keyPressed(KeyEvent e) {
if(e.getKeyChar()==10)
inputMonth();
}

//年份面板响应鼠标单击事件
void Year_mouseClicked(MouseEvent e) {
//SelectionYear();
inputYear();
}

//年份键盘敲击事件响应
void Year_keyPressed(KeyEvent e) {
//System.out.print(new Integer(e.getKeyChar()).byteValue());
if(e.getKeyChar()==10)
inputYear();
}

//检验输入的年份字符串
void inputYear() {
String s;
if(Year.getText().endsWith("年"))
{
s=Year.getText().substring(0,Year.getText().length()-1);
}
else s=Year.getText();
year=Integer.parseInt(s);
this.showMe();
}

//以字符串形式返回日期,yyyy-mm-dd
public String getDate(){return Out.getText();}

//以字符串形式输入日期,yyyy-mm-dd
public void setDate(String date){
if(date!=null){
StringTokenizer f = new StringTokenizer(date, "-");
if(f.hasMoreTokens())
year = Integer.parseInt(f.nextToken());
if(f.hasMoreTokens())
month = Integer.parseInt(f.nextToken());
if(f.hasMoreTokens())
day = Integer.parseInt(f.nextToken());
cal.set(year,month,day);
}
this.showMe();
}

//以日期对象形式输入日期
public void setTime(Date date){
cal.setTime(date);
this.iniCalender();
this.showMe();
}

//返回日期对象
public Date getTime(){return cal.getTime();}

//返回当前的日
public int getDay() {
return day;
}

//设置当前的日
public void setDay(int day) {
this.day = day;
cal.set(this.year,this.month,this.day);
this.showMe();
}

//设置当前的年
public void setYear(int year) {
this.year = year;
cal.set(this.year,this.month,this.day);
this.showMe();
}

//返回当前的年
public int getYear() {
return year;
}

//返回当前的月
public int getMonth() {
return month;
}

//设置当前的月
public void setMonth(int month) {
this.month = month;
cal.set(this.year,this.month,this.day);
this.showMe();
}

//刷新
public void showMe(){
this.showDays();
this.showMonth();
this.showYear();
this.showDate();
}

}