有点错误,请大家帮我看看……import java.awt.*;
import java.awt.event.*;
class Yuan extends Dialog implements ActionListener
{double r,area;
TextField 半径=null,
结果=null;
Button b=null;
Yuan(Frame f,String s,boolean mode)
{
super(f,s,mode);
setLayout(new FlowLayout());
半径=new TextField(10);
结果=new TextField(10);
b=new Button("ok");
add(new Lable("write the 半径"));
add(半径);
add(b);
add(new Lable("area is:"));
add(结果);
validate();
b.addActionListener(this);
setBounds(60,60,260,100);
addWindowsListener(new WindowsAdapter()
{public void windowsClosing(WindowsEvent e)
{setVisible(false);
}
}
);
}
public void actionPerformed(ActionEvent e)
{try
{
r=Double.parseDouble(半径.getText());
area=Math.PI*r*r;
结果.setText(" "+area);
}
catch(Exception ee)
{
半径.setText("请输入数字字符");
}
}
}
class 三角形 extends Dialog implements ActionListener
{double a=0,b=0,c=0,area;
TextField 边_a=new TextField(6);
TextField 边_b=new TextField(6);
TextField 边_c=new TextField(6);
TextField 结果=new TextField(8);
Button button=new Button("确定");
三角形(Frame f,String s,boolean mode)
{super(f,s,mode);
setLayout(new Lable("输入三边的长度:"));
add(边_a);add(边_b);add(边_c);
add(button);
add(new Lable("面积是:"));
add(结果);
validate();
button.addActionListener(this);
setButtons(60,60,360,100);
addWindowListener(new WindowAdapter()
{public void windowClosing(WindowEvent e)
{setVisible(false);
}
}
);
}
public void actionPerformed(ActionEvent e)//获得3边的长度
{try{a=Double.parseDouble(边_a.getText());
b=Double.parseDouble(边_b.getText());
c=Double.parseDouble(边_c.getText());
if(a+b>c&&a+c>b&&c+b>a)
{double p=(a+b+c)/2;
area=Math.sqrt(p*(p-a)*(p-b)*(p-c));
结果.setText(""+area);
}
else
{结果.setText("请输入数字字符");
}
}
catch(exception e)
{ System.out.println("有错误!");
}
}
}
class Win extends Frame implements ActionListener
{MenuBar bar=null;Menu mune=null;
MenuItem item1,item2;
Yuan circle;
三角形 trangle;
Win()
{bar=new MenuBar();
menu=new Menu("选择");
item1=new MeniItem("圆面积计算");
item2=new MenuItem("三角形面积计算");
menu.add(item1);
menu.add(item2);
bar.add(menu);
setMenuBar(bar);
circle=new Yuan(this,"计算圆面积",false);
teangle=new 三角形(this,"计算三角形面积",false);
item1.addActionListener(this);
item2.assActionListener(this);
setVisible(true);
setBounds(100,120,200,190);
addWindowListener(new WindowAdapter()
{public void windowClosing(WindowEvent e)
{System.exit(0);
}
}
);
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==item1)
{circle.setVisible(true);
}
else if(e.getSource()==item2)
{trangle.setVisible(true);
}
}
} public class Example8_2
{public static void main(String args[])
{Win win=new Win();
}
}
import java.awt.event.*;
class Yuan extends Dialog implements ActionListener
{double r,area;
TextField 半径=null,
结果=null;
Button b=null;
Yuan(Frame f,String s,boolean mode)
{
super(f,s,mode);
setLayout(new FlowLayout());
半径=new TextField(10);
结果=new TextField(10);
b=new Button("ok");
add(new Lable("write the 半径"));
add(半径);
add(b);
add(new Lable("area is:"));
add(结果);
validate();
b.addActionListener(this);
setBounds(60,60,260,100);
addWindowsListener(new WindowsAdapter()
{public void windowsClosing(WindowsEvent e)
{setVisible(false);
}
}
);
}
public void actionPerformed(ActionEvent e)
{try
{
r=Double.parseDouble(半径.getText());
area=Math.PI*r*r;
结果.setText(" "+area);
}
catch(Exception ee)
{
半径.setText("请输入数字字符");
}
}
}
class 三角形 extends Dialog implements ActionListener
{double a=0,b=0,c=0,area;
TextField 边_a=new TextField(6);
TextField 边_b=new TextField(6);
TextField 边_c=new TextField(6);
TextField 结果=new TextField(8);
Button button=new Button("确定");
三角形(Frame f,String s,boolean mode)
{super(f,s,mode);
setLayout(new Lable("输入三边的长度:"));
add(边_a);add(边_b);add(边_c);
add(button);
add(new Lable("面积是:"));
add(结果);
validate();
button.addActionListener(this);
setButtons(60,60,360,100);
addWindowListener(new WindowAdapter()
{public void windowClosing(WindowEvent e)
{setVisible(false);
}
}
);
}
public void actionPerformed(ActionEvent e)//获得3边的长度
{try{a=Double.parseDouble(边_a.getText());
b=Double.parseDouble(边_b.getText());
c=Double.parseDouble(边_c.getText());
if(a+b>c&&a+c>b&&c+b>a)
{double p=(a+b+c)/2;
area=Math.sqrt(p*(p-a)*(p-b)*(p-c));
结果.setText(""+area);
}
else
{结果.setText("请输入数字字符");
}
}
catch(exception e)
{ System.out.println("有错误!");
}
}
}
class Win extends Frame implements ActionListener
{MenuBar bar=null;Menu mune=null;
MenuItem item1,item2;
Yuan circle;
三角形 trangle;
Win()
{bar=new MenuBar();
menu=new Menu("选择");
item1=new MeniItem("圆面积计算");
item2=new MenuItem("三角形面积计算");
menu.add(item1);
menu.add(item2);
bar.add(menu);
setMenuBar(bar);
circle=new Yuan(this,"计算圆面积",false);
teangle=new 三角形(this,"计算三角形面积",false);
item1.addActionListener(this);
item2.assActionListener(this);
setVisible(true);
setBounds(100,120,200,190);
addWindowListener(new WindowAdapter()
{public void windowClosing(WindowEvent e)
{System.exit(0);
}
}
);
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==item1)
{circle.setVisible(true);
}
else if(e.getSource()==item2)
{trangle.setVisible(true);
}
}
} public class Example8_2
{public static void main(String args[])
{Win win=new Win();
}
}
double r, area;
TextField 半径 = null, 结果 = null;
Button b = null; Yuan(Frame f, String s, boolean mode) {
super(f, s, mode);
setLayout(new FlowLayout());
半径 = new TextField(10);
结果 = new TextField(10);
b = new Button("ok");
add(new Label("write the 半径"));
add(半径);
add(b);
add(new Label("area is:"));
add(结果);
validate();
b.addActionListener(this);
setBounds(60, 60, 260, 100);
addWindowListener(new WindowAdapter() {
public void windowsClosing(WindowEvent e) {
setVisible(false);
}
});
} public void actionPerformed(ActionEvent e) {
try {
r = Double.parseDouble(半径.getText());
area = Math.PI * r * r;
结果.setText(" " + area);
} catch (Exception ee) {
半径.setText("请输入数字字符");
}
}
}class 三角形 extends Dialog implements ActionListener {
double a = 0, b = 0, c = 0, area;
TextField 边_a = new TextField(6);
TextField 边_b = new TextField(6);
TextField 边_c = new TextField(6);
TextField 结果 = new TextField(8);
Button button = new Button("确定"); 三角形(Frame f, String s, boolean mode) {
super(f, s, mode);
add(new Label("输入三边的长度:"));
add(边_a);
add(边_b);
add(边_c);
add(button);
add(new Label("面积是:"));
add(结果);
validate();
button.addActionListener(this);
setBounds(60, 60, 360, 100);
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
setVisible(false);
}
});
} public void actionPerformed(ActionEvent e)// 获得3边的长度
{
try {
a = Double.parseDouble(边_a.getText());
b = Double.parseDouble(边_b.getText());
c = Double.parseDouble(边_c.getText());
if (a + b > c && a + c > b && c + b > a) {
double p = (a + b + c) / 2;
area = Math.sqrt(p * (p - a) * (p - b) * (p - c));
结果.setText("" + area);
} else {
结果.setText("请输入数字字符");
}
} catch (Exception e1) {
System.out.println("有错误!");
}
}
}class Win extends Frame implements ActionListener {
MenuBar bar = null;
Menu menu = null;
MenuItem item1, item2;
Yuan circle;
三角形 trangle; Win() {
bar = new MenuBar();
menu = new Menu("选择");
item1 = new MenuItem("圆面积计算");
item2 = new MenuItem("三角形面积计算");
menu.add(item1);
menu.add(item2);
bar.add(menu);
setMenuBar(bar);
circle = new Yuan(this, "计算圆面积", false);
trangle = new 三角形(this, "计算三角形面积", false);
item1.addActionListener(this);
item2.addActionListener(this);
setVisible(true);
setBounds(100, 120, 200, 190);
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
} public void actionPerformed(ActionEvent e) {
if (e.getSource() == item1) {
circle.setVisible(true);
} else if (e.getSource() == item2) {
trangle.setVisible(true);
}
}
}public class Example8_2 {
public static void main(String args[]) {
Win win = new Win();
}
}