很简单程序的编译出错,问题在哪里?请指教

Question

我只找到你的两个错误，在:
class Ingredients extends Panel{
    checkbox Ingredient1,Ingredient2,Ingredient3,Ingredient4;    Ingredients(){
    add(Checkbox Ingredient1 = new Checkbox("turkey"));
    add(Checkbox Ingredient2 = new Checkbox("r.beef"));
    add(Checkbox Ingredient3 = new Checkbox("pickle"));
    add(Checkbox Ingredient4 = new Checkbox("tomato"));
    }
}
中，第一行定义中checkbox改为大写Checkbox;
在add方法中，把Checkbox去掉，即：
add(Ingredient2 = new Checkbox("r.beef"));
...
其他仍有错误，你自己找一下吧！

Answer 1

你程序的问题太多了，大小写、定义只能给你改成这样，
import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;public class sandwich extends Applet implements ItemListener{
    Menu Panel1;
    Ingredients Panel2;
    public void init(){
    setLayout(new GridLayout(1,2));
    Panel1 = new Menu();
    add(Panel1);
    Panel2 = new Ingredients();
    Panel1.sandwich1.addItemListener(this);
    Panel1.sandwich2.addItemListener(this);
    Panel1.sandwich3.addItemListener(this);
    add(Panel2);
    }
public void itemStateChanged(ItemEvent event){
if(event.getItemSelectable() == Panel1.sandwich1){
    Panel2.Ingredient1.setState(true);
    Panel2.Ingredient2.setState(false);
    Panel2.Ingredient3.setState(true);
    Panel2.Ingredient4.setState(false);
    Panel2.Pricebox.setText("price: $2.95");
}
if(event.getItemSelectable() == Panel1.sandwich2){
    Panel2.Ingredient1.setState(false);
    Panel2.Ingredient2.setState(true);
    Panel2.Ingredient3.setState(true);
    Panel2.Ingredient4.setState(true);
    Panel2.Pricebox.setText("price: $2.95");
}
if(event.getItemSelectable() == Panel1.sandwich3){
    Panel2.Ingredient1.setState(true);
    Panel2.Ingredient2.setState(true);
    Panel2.Ingredient3.setState(true);
    Panel2.Ingredient4.setState(true);
    Panel2.Pricebox.setText("price: $4.00");
}}class Menu extends Panel{
    CheckboxGroup CGroup;
    Checkbox sandwich1,sandwich2,sandwich3;
    TextField Pricebox;
    
    Menu(){
        CGroup = new CheckboxGroup();
        add(sandwich1 = new Checkbox("Sandwich 1",CGroup,false));
        add(sandwich2 = new Checkbox("Sandwich 2",CGroup,false));
        add(sandwich3 = new Checkbox("Sandwich 3",CGroup,false));
        Pricebox = new TextField(15);
        add(Pricebox);
    }
}class Ingredients extends Panel{
    Checkbox Ingredient1,Ingredient2,Ingredient3,Ingredient4;
TextField Pricebox;
    Ingredients(){
    add( Ingredient1 = new Checkbox("turkey"));
    add( Ingredient2 = new Checkbox("r.beef"));
    add( Ingredient3 = new Checkbox("pickle"));
    add( Ingredient4 = new Checkbox("tomato"));
    Pricebox = new TextField(15);
    add(Pricebox);
    }
}
}