实训要求：
1.使用BorderLayout 进行总体布局
2.在North 位置放置包含两个按钮( 上月和下月)的Panel
3.在South 位置放置一个Label 用于显示当前年份和月份
4.在Center 位置放置一个显示日历的Panel
5.显示日历的Panel 设置7 行7 列的GridLayout 布局，其中第1行放置7
个按钮显示周“几”，其他6 行放置42 个Label 用于显示期。
6.启动程序时日历中默认显示当前月份的日历。
7.点击“上月”和“下月”可翻看上个月和下个月的日历。
8.程序运行结果如下图:
代码：
CalendaBean.java
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Calendar;
import javax.swing.*;
public class CalendaBean implements ActionListener {
JLabel[] label;
JLabel now;
String[] day;
int year = 0, month = 0;
public void setYear(int year) {
this.year = year;
}
public void setMonth(int month) {
this.month = month;
}
public void actionPerformed(ActionEvent e) {
String str = e.getActionCommand();
if (str.equals("lastmonth")) {
month--;
if (month == 0) {
month = 12;
year--;
}
}
else if (str.equals("nextmonth")) {
month++;
if (month == 13) {
month = 1;
year++;
}
}
now.setText("日历:" + year + "年" + month + "月");
String[] a = getCalendar();
for (int i = 0; i < a.length; i++) {
label[i].setText(" "+a[i]);
}
}
public String[] getCalendar() {
String[] a = new String[42];
Calendar rili = Calendar.getInstance();
rili.set(year, month - 1, 1);
int weekDay = rili.get(Calendar.DAY_OF_WEEK) - 1;
int day = 0;
if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8
|| month == 10 || month == 12) {
day = 31;
}
if (month == 4 || month == 6 || month == 9 || month == 11) {
day = 30;
}
if (month == 2) {
if ((year % 4 == 0) && (year % 100 != 0) || (year % 400 == 0))
day = 29;
else
day = 28;
}
for (int i = 0; i < weekDay; i++)
a[i] = " ";
for (int i = weekDay, n = 1; i < weekDay + day; i++) {
a[i] = String.valueOf(n);
n++;
}
for (int i = weekDay + day; i < a.length; i++)
a[i] = " ";
return a;
}
}Test.java
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Test extends JFrame {
JButton b1, b2, b3, b4, b5, b6, b7, bx, by;
CalendaBean cb = new CalendaBean();
JLabel[] label;
JLabel now;
public static void main(String[] args) {
Test frame = new Test();
frame.setSize(500, 400);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setTitle("日历");
frame.setVisible(true);
}
public Test() {
int year, month;
setLayout(new BorderLayout());
JPanel pNorth = new JPanel();
cb = new CalendaBean();
cb.setYear(2017);
cb.setMonth(11);
String[] a = cb.getCalendar();
bx = new JButton("上月");
by = new JButton("下月");
bx.setActionCommand("lastmonth");
by.setActionCommand("nextmonth");
bx.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
cb.actionPerformed(e);
}
});
by.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
cb.actionPerformed(e);
}
});
pNorth.add(bx);
pNorth.add(by);
add(pNorth, BorderLayout.NORTH);
GridLayout grid = new GridLayout(7, 7);
JPanel pCenter = new JPanel();
b1 = new JButton("日");
b2 = new JButton("一");
b3 = new JButton("二");
b4 = new JButton("三");
b5 = new JButton("四");
b6 = new JButton("五");
b7 = new JButton("六");
pCenter.add(b1);
pCenter.add(b2);
pCenter.add(b3);
pCenter.add(b4);
pCenter.add(b5);
pCenter.add(b6);
pCenter.add(b7);
label = new JLabel[42];
for (int i = 0; i < 42; i++) {
label[i] = new JLabel();
pCenter.add(label[i]);
}
cb.label = this.label;
for (int i = 0; i < a.length; i++) {
label[i].setText(" "+a[i]);
}
pCenter.setLayout(grid);
add(pCenter, BorderLayout.CENTER);
JPanel pSouth = new JPanel();
now = new JLabel();
now.setText("日历:" + cb.year + "年" + cb.month + "月");
cb.now = now;
pSouth.add(now);
add(pSouth, BorderLayout.SOUTH);
}
}
运行结果：
