Java Swing-10 Swing实例08Jlist

• [ 声明] 学习笔记和代码均参考自徐彤老师（ITFlight）的视频

package demo08;

import java.awt.FlowLayout;

import javax.swing.JFrame;
import javax.swing.JList;

public class Demo1 extends JFrame{
	
	String value[]= {"Aaa","B","Ccccc","D"};
	JList list=new JList(value);
	public Demo1() {
		setSize(500,500);
		this.setLayout(new FlowLayout());
		add(list);
		setVisible(true);
	}
	
	
	public static void main(String[] args) {
		
		new Demo1();

	}

}

package demo08;

import java.awt.FlowLayout;

import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;

public class Demo2 extends JFrame{
	
	String value[]= {"Aaa","B","Ccccc","D"};
	JList list=new JList(value);
	public Demo2() {
		setSize(500,500);
		this.setLayout(new FlowLayout());
		add(list);
		list.addListSelectionListener(new ListSelectionListener() {
			
			@Override
			public void valueChanged(ListSelectionEvent e) {
//				String str=(String)list.getSelectedValue();
//				System.out.println(str);
				int x=list.getSelectedIndex();
				System.out.println(value[x]);
			}
		});
		setVisible(true);
	}
	
	
	public static void main(String[] args) {
		
		new Demo2();

	}

}

package demo08;

import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Enumeration;
import java.util.Vector;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JTextField;

public class Demo3 extends JFrame implements ActionListener{
	
	JButton button1=new JButton("add");
	JButton button2=new JButton("delete");
	JButton button3=new JButton("update");
	JButton button4=new JButton("select");
	JTextField tf=new JTextField(30);
	
	Vector value=new Vector();
	JList list=new JList(value);
	
	public Demo3() {
		setSize(500,500);
		value.add("111");
		value.add("222");
		value.add("333");
		value.add("444");
		this.setLayout(new FlowLayout());
		add(list);
		add(button1);
		add(button2);
		add(button3);
		add(button4);
		button1.addActionListener(this);
		button2.addActionListener(this);
		button3.addActionListener(this);
		button4.addActionListener(this);
		add(tf);
		setVisible(true);
	}
	
	public void actionPerformed(ActionEvent e) {
		if(e.getSource()==button1) {
			value.add("xxx");
			list.updateUI();

		}
		else if(e.getSource()==button2) {	
			int index=list.getSelectedIndex();//找到点击的第几个元素
			value.remove(index);
			list.updateUI();	//在操作之后更新界面
		}
		else if(e.getSource()==button3) {
			int index=list.getSelectedIndex();
			value.remove(index);
			value.add("000");
			list.updateUI();
		}
		else if(e.getSource()==button4) {
			Object o[]=list.getSelectedValues();
			for (int i = 0; i < o.length; i++) {
				System.out.println(o[i]);
			}
			Enumeration e2=value.elements();
			while(e2.hasMoreElements()) {
				tf.setText(tf.getText()+e2.nextElement());
			}
		}
	}
	
	public static void main(String[] args) {
		
		new Demo3();

	}

}