Question

用Java如何实现界面的功能？

package ied.grademanager.service;

import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;

import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPasswordField;
import javax.swing.JTextField;

public class RegisterDemo extends JFrame{
JLabel lblName,lblPwd,lblpic,lblhead;
JTextField txtName,txthead,txtheadImg;
JPasswordField txtPwd;
JButton btnRegister,btnLogin;
public RegisterDemo(){
super("注册界面");
Container cc = this.getContentPane();
cc.setLayout(null);
init();
cc.add(lblName);
cc.add(lblPwd);
cc.add(lblhead);
cc.add(txtName);
cc.add(txthead);
cc.add(txtheadImg);
cc.add(txtPwd);
cc.add(btnRegister);
cc.add(btnLogin);
cc.add(lblpic);
this.setDefaultCloseOperation(3);
this.setVisible(true);
this.setSize(504,333);
this.setLocationRelativeTo(null);

}

private void init() {
// TODO 自动生成的方法存根
lblpic=new JLabel(new ImageIcon("src\\ied\\grademanager\\service\\3.jpg"));
lblpic.setBounds(0, 0, 504,333);
lblName = new JLabel("账号：");
lblName.setBounds(110,100,100,30);
txtName = new JTextField(10);
txtName.setBounds(152, 100,100,30);
lblPwd = new JLabel("密码：");
lblPwd.setBounds(110,140,100,30);
txtPwd = new JPasswordField(10);
txtPwd.setBounds(152,140,100,30);
lblhead=new JLabel("头像:");
lblhead.setBounds(110, 180, 100, 30);
txthead= new JTextField("点击选择上传图片");
txthead.setBounds(152, 180,100, 30);

btnRegister = new JButton("快速注册");
btnRegister.setBounds(152,220,100,30);
btnRegister.addActionListener(new ActionListener() {

@Override
public void actionPerformed(ActionEvent e) {
// TODO 自动生成的方法存根
String username=txtName.getText();
if(username==null||"".equals(username.trim())){
JOptionPane.showMessageDialog(null,"账号不能为空");
return;
}
String password=new String(txtPwd.getPassword());
if(password==null||"".equals(password.trim())){
JOptionPane.showMessageDialog(null, "密码不能为空");
return;
}
String headImg=txtheadImg.getText();
File file=new File(headImg);
if(!file.exists()){
JOptionPane.showMessageDialog(null, "文件不存在请先选择文件");

}
}

}

btnLogin = new JButton("返回登录");
btnLogin.setBounds(152,260,100,30);

}

public static void main(String[] args) {
// TODO 自动生成的方法存根
new RegisterDemo();
}

}

Answer 1

在java中怎样实现多个界面之间的切换 用Iframe 就可以了

补充：Java是一种可以撰写跨平台应用软件的面向对象的程序设计语言。Java 技术具有卓越的通用性、高效性、平台移植性和安全性，广泛应用于PC、数据中心、游戏控制台、科学超级计算机、移动电话和互联网，同时拥有全球最大的开发者专业社群。

Answer 2

新建一个窗口，然后实现一个关闭按钮”窗口的功能
import java.awt.*;
import java.awt.event.*;

public class TestWindowEvent {
public static void main (String[] args) {
new Frame88 ("WindowAdapter");
}
}
class Frame88 extends Frame {
Frame88 (String s) {
super(s);
setBounds (300,300,200,70);
setLayout (null);
setVisible (true);
addWindowListener (new WindowAdapter() {
public void windowClosing(WindowEvent e) {
setVisible (false);
System.exit(0);
}
} );
}
}