急，如何让JPanel随着中用Graphics2D的scale方法自动缩放，同时让滚动条自动变化

[freelb]

求救，做了一个打印预览，在一个JPanel里面绘制了表格,让Graphics2D的scale方法自动缩放，同时想让JPanel也自动缩放，绘制内容的JPanel是放在JScrollPane里面的，主要的目的是想让滚动条随着绘制的内容的缩放而自动变化,各位同行，请问怎样实现？帮帮忙

[gzhcn]

我也遇到了同样的问题，求高人解答

[Inhibitory]

下面只是实现功能代码，自己集成到你的程序中去

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;

public class Test {
	public static void main(String[] args) {
		final JFrame frame = new JFrame();
		
		final JPanel panel = new JPanel();
		panel.setBackground(Color.GREEN);
		panel.setPreferredSize(new Dimension(800,200));
		frame.getContentPane().add(new JScrollPane(panel));
		
		JButton zoomOutButton = new JButton("缩小");
		JButton zoomInButton = new JButton("放大");
		JPanel buttonsPanel = new JPanel();
		buttonsPanel.add(zoomOutButton);
		buttonsPanel.add(zoomInButton);
		frame.getContentPane().add(buttonsPanel, BorderLayout.NORTH);
		
		zoomOutButton.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				int width = panel.getWidth() - 100;
				int height = panel.getHeight();
				
				panel.setPreferredSize(new Dimension(width, height));
				panel.revalidate(); // 重点是这一句，使得布局生效
			}
		});
		
		
		zoomInButton.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				int width = panel.getWidth() + 100;
				int height = panel.getHeight();
				
				panel.setPreferredSize(new Dimension(width, height));
				panel.revalidate();
			}
		});
		
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.setSize(600, 600);
		frame.setLocationRelativeTo(null);
		frame.setVisible(true);
	}
}

[huntor]

先缩放JPanel，在重绘时缩放绘制的图形。