heart.java

一个简单的画心型线的程序比较简单的gui程序!欢迎大家下载学习交流!

package mycode;

import java.awt.*;
import java.awt.event.*;

public class Heart extends Frame implements WindowListener, ComponentListener,
		ItemListener {
	int width1 = 200, height1 = 200; // 窗口尺寸

	Color color = Color.blue; // 画线的颜色

	CheckboxGroup cg1;

	Checkbox cb1, cb2, cb3;

	public Heart() {
		setTitle("Heart");
		setSize(width1, height1);
		setBackground(Color.white);
		setLayout(new FlowLayout());
		addWindowListener(this);
		addComponentListener(this);
		cg1 = new CheckboxGroup();
		cb1 = new Checkbox("blue", cg1, true);
		cb2 = new Checkbox("red", cg1, false);
		cb3 = new Checkbox("green", cg1, false);
		cb1.addItemListener(this);
		cb2.addItemListener(this);
		cb3.addItemListener(this);
		add(cb1);
		add(cb2);
		add(cb3);
	}

	public void paint(Graphics g) {
		int x0, y0; // 原点坐标
		x0 = width1 / 2;
		y0 = height1 / 2;
		g.setColor(color);
		g.drawLine(x0, 0, x0, height1);
		g.drawLine(0, y0, width1, y0);
		int i, j = 40, x, y;
		double pi = 3.14, angle, r;
		while (j < 200) {
			for (i = 0; i < 1023; i++) {
				angle = i * pi / 512;
				r = j * (1 - Math.cos(angle));
				x = (int) Math.round(r * Math.cos(angle) * 2);
				y = (int) Math.round(r * Math.sin(angle));
				g.fillOval(x0 + x, y0 + y, 1, 1); // 画圆点
			}
			j = j + 20;
		}
	}

	public void windowClosing(WindowEvent e) // 关闭窗口
	{
		System.exit(0);
	}

	public void componentResized(ComponentEvent e) // 改变窗口大小时
	{
		width1 = getWidth(); // 取得窗口的大小
		height1 = getHeight();
	}

	public void itemStateChanged(ItemEvent e) { // 选中单选按钮时
		if (e.getSource() == cb1) // 判断产生事件对象e的组件是谁
			color = Color.blue;
		if (cb2.getState()) // 判断单选按钮cb2的状态
			color = Color.red;
		if (cg1.getSelectedCheckbox() == cb3) // 判断复选框组cg1选中的是谁
			color = Color.green;
		repaint(); // 重画
	}

	public static void main(String arg[]) { // 创建并显示Frame对象，Frame作为画布
		new Heart().setVisible(true);
	}

	public void componentMoved(ComponentEvent e) {
	}

	public void componentHidden(ComponentEvent e) {
	}

	public void componentShown(ComponentEvent e) {
	}

	public void windowOpened(WindowEvent e) {
	}

	public void windowActivated(WindowEvent e) {
	}

	public void windowDeactivated(WindowEvent e) {
	}

	public void windowClosed(WindowEvent e) {
	}

	public void windowIconified(WindowEvent e) {
	}

	public void windowDeiconified(WindowEvent e) {
	}
}