Question

错误：需要class，interface或enum import java.awt.*;

书上的例题
improt java.awt.*;
public class LoginFrame extends Frame
{
public LoginFrame()
{
super("User Login");
this.setSize(280,120);
this.setLocation(300,240);
this.setBlackground(Color.lightGray);
this.setLayout(new FlowLayout());
this.add(new Label("userid"));
this.add(new TextField("user1",20));
this.add(new Label("password"));
this.add(new Button("OK"));
this.add(new Button("Cancel"));
this.add(new TextField(20));
this.setVisible(true);
}
public static void main(String arg[])
{
new LoginFrame();
}
}
编译的时候出现这个错误

Answer 1

你的代码写错了，this.setBlackground(Color.lightGray);改成this.setBackground(Color.lightGray);

完整代码如下：

package com.test;
import java.awt.Button;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.Label;
import java.awt.TextField;
public class LoginFrame extends Frame
{
public LoginFrame()
{
super("User Login");
this.setSize(280,120);
this.setLocation(300,240);
this.setBackground(Color.lightGray);
this.setLayout(new FlowLayout());
this.add(new Label("userid"));
this.add(new TextField("user1",20));
this.add(new Label("password"));
this.add(new Button("OK"));
this.add(new Button("Cancel"));
this.add(new TextField(20));
this.setVisible(true);
}
public static void main(String arg[])
{
new LoginFrame();
}
}

Answer 2

improt java.awt.*;
添加了对应的jar包??你可以使用myeclipse或者eclipse的，编译的时候就会提示你
我感觉java编译工具还是比较适合初学者的

Answer 3

import java.awt.*;
public class LoginFrame extends Frame
{
public LoginFrame()
{
super("User Login");
this.setSize(280,120);
this.setLocation(300,240);
this.setBackground(Color.lightGray);
this.setLayout(new FlowLayout());
this.add(new Label("userid"));
this.add(new TextField("user1",20));
this.add(new Label("password"));
this.add(new Button("OK"));
this.add(new Button("Cancel"));
this.add(new TextField(20));
this.setVisible(true);
}
public static void main(String arg[])
{
new LoginFrame();
}
}
这样就对了
什么书上的错误。明显就是你手写输入有误

Answer 4

improt写错了，应该是import