JToolBar工具栏的简单实例(2)

package Assis;

import javax.swing.JFrame;
import javax.swing.JToolBar;
import javax.swing.JScrollPane;
import javax.swing.JButton;
import javax.swing.ImageIcon;
import java.awt.Image;
import java.awt.Container;
import java.awt.BorderLayout;
import java.awt.TextArea;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.net.URL;

public class ToolBarDemo extends JFrame implements ActionListener {
	private static final long serialVersionUID = 1L;
	TextArea textarea;

	public static void main(String arg[]) {
		new ToolBarDemo();
	}

	public ToolBarDemo() {
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		buildFrame();
		setLocation(250, 150);
		setSize(300, 200);
		setVisible(true);
	}

	private void buildFrame() {
		Container pane = getContentPane();
		pane.setLayout(new BorderLayout());

		textarea = new TextArea(4, 20);
		textarea.setEditable(false);
		JScrollPane scroll = new JScrollPane(textarea);
		pane.add(scroll, BorderLayout.CENTER);

		JToolBar toolbar = new JToolBar();// 建立工具栏
		toolbar.add(makeToolButton(null, "anchor"));
		toolbar.add(makeToolButton(null, "hammer"));
		toolbar.add(makeToolButton(null, "file"));
		toolbar.add(makeToolButton(null, "spinner"));
		pane.add(toolbar, BorderLayout.NORTH);

		pack();
	}

	private JButton makeToolButton(String filename, String command) {// 创建按钮
		ImageIcon imageicon = null;
		if (filename != null) {
			imageicon = getImageIcon(filename);
			Image image = imageicon.getImage();
			image = image.getScaledInstance(16, 16, Image.SCALE_DEFAULT);// 创建图片的缩放版本
			imageicon.setImage(image);
		}
		JButton button = new JButton(imageicon);
		button.setActionCommand(command);
		button.addActionListener(this);
		return (button);
	}

	/** 获取图片图标 */
	public static final ImageIcon getImageIcon(String url) {
		return new ImageIcon(getURL(url));
	}

	/** 获得文件的绝对地址 */
	public static final URL getURL(String path) {
		return "".getClass().getResource(path);
	}

	public void actionPerformed(ActionEvent e) {
		String selection = e.getActionCommand();
		textarea.append("\n" + selection);
		textarea.repaint();
	}
}