泪求程序 在一个窗口里有两个按钮 矩形 和圆 点击一个 自动画图形

[sk3212635]

哥哥姐姐帮忙拉

[boboo_2000_0]

楼主可以使用Java AWT里面Graghic类提供的画图方法画，很简单的。

[gentalguo]

这问题描述的。罢了，刚好闲着，也算练练敲键盘的速度。
你不是泪求吗？好，代码给你，希望你继续哭下去哈~~

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

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

public class GraphicDemo extends JFrame {

	private static final long serialVersionUID = 1L;
	GraphicPanel gp;

	public GraphicDemo() {
		super();

		Container c = getContentPane();
		c.setLayout(new BorderLayout());
		gp = new GraphicPanel();
		gp.setBorder(BorderFactory.createLineBorder(Color.black));
		c.add(gp);

		JPanel p = new JPanel();
		p.setLayout(new FlowLayout());
		JButton rButton = new JButton("Rect");
		JButton oButton = new JButton("Oval");
		rButton.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				// TODO Auto-generated method stub
				gp.setIsRect(true);
				gp.repaint();
			}
		});

		oButton.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				gp.setIsRect(false);
				gp.repaint();
			}
		});

		p.add(rButton);
		p.add(oButton);
		c.add(p, BorderLayout.SOUTH);

		setSize(600, 400);
		setDefaultCloseOperation(EXIT_ON_CLOSE);
		setLocationRelativeTo(null);
		setVisible(true);
	}

	private class GraphicPanel extends JPanel {

		private static final long serialVersionUID = 1L;
		boolean isRect = false;

		public GraphicPanel() {
			super();

		}

		public void setIsRect(boolean flag) {
			isRect = flag;
		}

		@Override
		public void paint(Graphics g) {
			super.paint(g);
			Rectangle r = getBounds();
			Rectangle rect = new Rectangle();
			rect.width = rect.height = (int) (Math.min(r.width, r.height) * 0.8);
			rect.x = (r.width - rect.width) / 2;
			rect.y = (r.height - rect.height) / 2;
			if (isRect) {
				g.drawRect(rect.x, rect.y, rect.width, rect.height);
			} else {
				g.drawOval(rect.x, rect.y, rect.width, rect.height);
			}
		}
	}

	public static void main(String[] args) {
		new GraphicDemo();
	}
}