JAVA学习笔记(二)

这星期通过学习了异常处理和事件监听，在程序中也能实现，不过功能不是很好。主要做了个单选框，添加事件响应，但做出来的时候界面不能直接显示出那些按钮以及标签，必须拖动一下界面大小才能显示出来，希望老师可以帮助解决一下。
package 登录界面;

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;

public class Login {
private JFrame frame;
public Login()
{
makeFrame();
}
private void makeFrame() {
final String userName = "2014330331";
final String passwrod = "1";
frame = new JFrame("Login");
Container contentPane = frame.getContentPane();
JLabel fileLabel = new JLabel("welcome to visit");
contentPane.add(fileLabel,BorderLayout.NORTH);
JLabel statusLabel = new JLabel("Version 2016");
contentPane.add(statusLabel,BorderLayout.SOUTH);
frame.pack();
frame.setSize(500, 300);
frame.setVisible(true);

    //关闭窗口结束进程
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    
    //确定界面的组件的布局
    JPanel westPanel = new JPanel (new FlowLayout(FlowLayout.CENTER));
    JPanel inwestPanel = new JPanel(new GridLayout(4,1));
    westPanel.add(inwestPanel);
    contentPane.add(westPanel,BorderLayout.CENTER);
    
    //添加组件以及事件监听
    JLabel l1 = new JLabel("账号");
    JLabel l2 = new JLabel("密码");
    JTextField t1 = new JTextField(15);
    JPasswordField t2 =new JPasswordField(15);
    JCheckBox c1 = new JCheckBox("记住密码");
    JCheckBox c2 = new JCheckBox("自动登录");
    JButton b1 = new JButton("登录");
    b1.addActionListener(new ActionListener(){
		@Override
		public void actionPerformed(ActionEvent e) {
			// TODO Auto-generated method stub
			if(userName.equals(t1.getText()) && passwrod.equals(t2.getText())) {
				JOptionPane.showMessageDialog(null, "登陆成功", "提示", JOptionPane.INFORMATION_MESSAGE);
				} else {
				JOptionPane.showMessageDialog(null, "错误", "提示", JOptionPane.ERROR_MESSAGE);
				t1.setText("");
				t2.setText("");
				}
		}
    });
    JButton b2 = new JButton("退出");
	JPanel p1 = new JPanel();
	p1.add(l1);
	p1.add(t1);
	inwestPanel.add(p1);
    JPanel p2 = new JPanel();
    p2.add(l2);
    p2.add(t2);
    inwestPanel.add(p2);
    JPanel p3 = new JPanel();
    p3.add(c1);
    p3.add(c2);
    inwestPanel.add(p3);
    JPanel p4 = new JPanel();
    p4.add(b1);
    p4.add(b2);
    inwestPanel.add(p4);
    
    //将窗口放在屏幕中央
    int windowWidth = frame.getWidth();                   
    int windowHeight = frame.getHeight();                      
    Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();          
    int screenWidth = screenSize.width;                     
    int screenHeight = screenSize.height;                   
    frame.setLocation(screenWidth/2-windowWidth/2, screenHeight/2-windowHeight/2);
}

public void panel(){
	
}
public static void main(String[] args){
	// TODO Auto-generated method stub
	new Login();
}

}