1. 声音文件的播放
1.1 在Applet中播放声音
在Applet中，可以使用AudioClip来播放声音，它非常简单，只有三个方法：play()、loop()和stop()。
例1.1 利用AudioClip播放声音文件。
package duomeiti;
import java.applet.Applet;
import java.applet.AudioClip;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
public class playMusic extends Applet implements ActionListener {
AudioClip clip = null;
JButton playBtn,loopBtn,stopBtn;
public void init(){
playBtn = new JButton("播放");
loopBtn = new JButton("循环");
stopBtn = new JButton("停止");
playBtn.addActionListener(this);
loopBtn.addActionListener(this);
stopBtn.addActionListener(this);
add(playBtn);
add(loopBtn);
add(stopBtn);
clip = getAudioClip(getCodeBase(),"test.wav");
}
public void actionPerformed(ActionEvent e) {
if(e.getSource()==playBtn)
clip.play();
else if(e.getSource()==loopBtn)
clip.loop();
else
clip.stop();
}
}
1.2 在Application中播放声音
它的一般用法是，先用AudioStream创建一个音频流对象，而后将此对象作为参数传递给AudioPlayer.player.start()方法以便播放。虽然AudioPlayer.player中只有start()和stop()两个方法，但是start()方法会从音频流对象上次停止播放的位置开始播放，而不是从头开始播放。所以用stop()暂停一个音频流的播放后，可以使用start()继续播放。
例1.2 在Application中播放声音文件。
package duomeiti;
import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.HeadlessException;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import javax.swing.*;
import sun.audio.AudioPlayer;
import sun.audio.AudioStream;
public class playAudio implements ActionListener {
protected JTextField fileField;
protected JButton openBtn,startBtn,pauseBtn,resumBtn,stopBtn;
protected Container con;
protected JFrame jf;
protected AudioStream as;
protected FileInputStream fis;
public playAudio(){
jf = new JFrame("播放声音");
con = jf.getContentPane();
con.setLayout(new FlowLayout());
fileField = new JTextField();
fileField.setColumns(30);
openBtn = new JButton("选择文件");
startBtn = new JButton("开始播放");
pauseBtn = new JButton("暂停播放");
resumBtn = new JButton("继续播放");
stopBtn = new JButton("停止播放");
openBtn.addActionListener(this);
startBtn.addActionListener(this);
pauseBtn.addActionListener(this);
resumBtn.addActionListener(this);
stopBtn.addActionListener(this);
con.add(fileField);
con.add(openBtn);
con.add(startBtn);
con.add(pauseBtn);
con.add(resumBtn);
con.add(stopBtn);
jf.setSize(500, 400);
jf.setLocation(300, 200);
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void actionPerformed(ActionEvent e) {
Object obj;
obj = e.getSource();
try {
if(obj==openBtn)
openfile();
else if(obj==startBtn){
if(fis!=null) fis.close();
fis = new FileInputStream(fileField.getText());
as = new AudioStream(fis);
AudioPlayer.player.start(as);
}else if(obj==pauseBtn)
AudioPlayer.player.stop(as);
else if(obj==resumBtn)
AudioPlayer.player.start(as);
else if(obj==stopBtn){
AudioPlayer.player.stop(as);
as.close();
fis.close();
fis = null;
}
} catch (FileNotFoundException e1) {
JOptionPane.showMessageDialog(jf, "文件没有找到！");
} catch (IOException e1) {
JOptionPane.showMessageDialog(jf, "无法播放文件！");
}
}
private void openfile() {
try {
JFileChooser chooser = new JFileChooser();
if(chooser.showOpenDialog(jf)==JFileChooser.APPROVE_OPTION)
fileField.setText(chooser.getSelectedFile().toString());
} catch (Exception e) {
JOptionPane.showMessageDialog(jf, "无法加载文件！");
}
}
public static void main(String[] args) {
new playAudio();
}
}
2. 基本图形处理
2.1 图形的缩放
例2.1 缩放图形示例
package duomeiti;
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.*;
public class ResizeOval {
JFrame jf;
MyCanvas palette;
public class MyCanvas extends JPanel{
protected void paintComponent(Graphics g) {
int height,width;
height = getHeight();
width = getWidth();
g.setColor(Color.RED);
g.fillOval(0, 0, width, height);
}
}
public ResizeOval(){
jf = new JFrame("图形缩放示例");
palette = new MyCanvas();
jf.getContentPane().add(palette);
jf.setSize(500, 400);
jf.setLocation(300,200);
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public static void main(String[] args) {
new ResizeOval();
}
}
2.2 淡入淡出效果
要实现淡入淡出效果方法非常简单，只要采用HSB（色调-饱和度-亮度）模式设置色彩，其中的色调和亮度不必变化，只要调整饱和度的值即可。如果是淡入，则让饱和度逐步增加；如果是淡出，则让饱和度逐步减少。
例2.2 淡入淡出效果示例。
package duomeiti;
import java.awt.Color;
import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class fadeInOut {
JFrame jf;
JPanel jp;
Container con;
dealPushBtn handleBtn;
JButton btn;
public class dealPushBtn implements ActionListener{
public void actionPerformed(ActionEvent e) {
Graphics g = jp.getGraphics();
float h = 0.0f;
float s = 0.0f;
float b = 1.0f;
for(int i=0;i<100;i++){
g.setColor(Color.getHSBColor(h, s, b));
g.fillRect(0, 50, 300, 300);
try {
Thread.sleep(50);
} catch (InterruptedException e1) {
e1.printStackTrace();
}
s+=0.01;
}
for(int i=0;i<100;i++){
g.setColor(Color.getHSBColor(h, s, b));
g.fillRect(0, 50, 300, 300);
try {
Thread.sleep(50);
} catch (InterruptedException e1) {
e1.printStackTrace();
}
s-=0.01;
}
}
}
public fadeInOut(){
jf = new JFrame("色彩淡入淡出示例");
jp = new JPanel();
jp.setLayout(new FlowLayout());
handleBtn = new dealPushBtn();
btn= new JButton("开始");
btn.addActionListener(handleBtn);
con = jf.getContentPane();
jp.add(btn);
con.add(jp);
jf.setSize(300, 300);
jf.setLocation(300, 200);
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public static void main(String[] args) {
new fadeInOut();
}
}
2.3 透明效果
设置前景色的透明度，可以使得前景色和后景色能够混合起来，这需要使用Graphics2D类。
例2.3 色彩混合效果示例。
package duomeiti;
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Composite;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import javax.swing.*;
public class TransparencyExample extends JPanel {
private static int gap=10, width=40, offset=10,deltax=gap+width+offset;
private Rectangle blueSquare = new Rectangle(gap+offset,gap+offset,width,width),
redSquare = new Rectangle(gap,gap,width,width);
//创建一个指定alpha值的AlphaComposite对象
private AlphaComposite makeComposite(float alpha){
int type = AlphaComposite.SRC_OVER;
return (AlphaComposite.getInstance(type, alpha));
}
//用指定的alpha值来绘制前景色
private void drawSquares(Graphics2D g2d,float alpha){
Composite originalComposite = g2d.getComposite();
//用默认透明度绘制背景蓝色
g2d.setPaint(Color.blue);
g2d.fill(blueSquare);
//设置透明度，准备绘制前景红色
g2d.setComposite(makeComposite(alpha));
g2d.setPaint(Color.red);
g2d.fill(redSquare);
//将透明度设置回默认的模式
g2d.setComposite(originalComposite);
}
//分别用不同的透明度来绘制颜色
public void paintComponent(Graphics g){
super.paintComponent(g);
Graphics2D g2d = (Graphics2D)g;
for(int i=0;i<11;i++){
//alpha值逐步增大，透明度逐步减小
drawSquares(g2d,i*0.1F);
g2d.translate(deltax, 0);
}
}
}
package duomeiti;
import javax.swing.*;
import java.awt.*;
public class mixing {
JFrame jf;
TransparencyExample palette;
public mixing(){
jf = new JFrame("色彩混合示例");
palette = new TransparencyExample();
jf.getContentPane().add(palette);
jf.setSize(700, 400);
jf.setLocation(300, 200);
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public static void main(String[] args) {
new mixing();
}
}
3. 字体的处理
3.1 确定可用字体
例3.1 获取系统中安装的字体示例。
package duomeiti;
import java.awt.GraphicsEnvironment;
import javax.swing.*;
public class GetFonts {
private JFrame jf;
private JList nameList;
private JScrollPane nameSPane;
public GetFonts(){
jf = new JFrame("获取系统字体");
//获得GraphicsEnvironment类型的对象引用
GraphicsEnvironment eq = GraphicsEnvironment.getLocalGraphicsEnvironment();
//获取所有的字体家族名
String[] availableFonts = eq.getAvailableFontFamilyNames();
//存放到列表框中
nameList = new JList(availableFonts);
nameSPane = new JScrollPane(nameList);
jf.add(nameSPane);
jf.setSize(500, 400);
jf.setLocation(300, 200);
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public static void main(String[] args) {
new GetFonts();
}
}
3.2 创建字体对象
例3.2 创建和使用字体示例。
package duomeiti;
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class ShowFonts implements ActionListener {
private JFrame jf;
private JComboBox nameBox,styleBox;
private JTextField sizeText;
private JLabel fontLabel;
private JButton showBtn;
private JPanel panel;
public ShowFonts(){
jf = new JFrame("显示指定字体");
//显示系统可用字体
GraphicsEnvironment eq = GraphicsEnvironment.getLocalGraphicsEnvironment();
String[] availableFonts = eq.getAvailableFontFamilyNames();
nameBox = new JComboBox(availableFonts);
nameBox.setEditable(true);
nameBox.setSelectedItem("宋体");
//显示字体风格由用户选择
String[] style = {"正常","粗体","斜体","粗斜体"};
styleBox = new JComboBox(style);
styleBox.setEditable(false);
//由用户输入想要的字体尺寸
sizeText = new JTextField("12");
sizeText.setColumns(4);
//标签用于显示用户选择的字体
fontLabel = new JLabel("字体示例");
//创建按钮并安装监听器
showBtn = new JButton("显示字体");
showBtn.addActionListener(this);
//在窗口中排列组件
panel = new JPanel();
panel.setLayout(new FlowLayout());
panel.add(nameBox);
panel.add(styleBox);
panel.add(sizeText);
jf.add(panel, BorderLayout.NORTH);
jf.add(fontLabel, BorderLayout.CENTER);
jf.add(showBtn, BorderLayout.SOUTH);
jf.setSize(500, 400);
jf.setLocation(300, 200);
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void actionPerformed(ActionEvent e) {
//分别获取用户选择输入的字体信息
int styleIndex = styleBox.getSelectedIndex();
String fontStr = (String)nameBox.getSelectedItem();
int fontSize = Integer.parseInt(sizeText.getText());
//组合字体对象
Font userFont = new Font(fontStr,styleIndex,fontSize);
//为标签设置新的字体并显示
fontLabel.setFont(userFont);
}
public static void main(String[] args) {
new ShowFonts();
}
}
4. 字体的展示处理
例4.1 自行管理字体示例。
package duomeiti;
import javax.swing.*;
import java.awt.*;
public class FontsCanvas extends JPanel {
private String msg;
public FontsCanvas(String s){
msg = s;
setBackground(Color.white);
}
public FontsCanvas(){
this("自行管理字体示例");
}
public void paintComponent(Graphics g){
int maxWidth = getWidth(); //获取画布的宽度
int showX; //文字输出的横坐标位置
int showY = 0; //文字输出的纵坐标位置
int descent = 0; //文字下半部所占位置
int ascent = 0; //文字上半部所占位置
int leading = 0; //行间距
int totalWidth; //字符串所占宽度
FontMetrics fm; //用于自行管理字体
Font myFonts [] = new Font[4];
//创建不同的字体准备显示
myFonts[0] = new Font("宋体",Font.PLAIN,12);
myFonts[1] = new Font("仿宋",Font.BOLD,24);
myFonts[2] = new Font("黑体",Font.ITALIC,48);
myFonts[3] = new Font("楷体_GB2312",Font.ITALIC|Font.BOLD,60);
//用上述4种不同的字体显示同一个字符串，右对齐
for(int i=0;i<myFonts.length;i++){
g.setFont(myFonts[i]);
fm = g.getFontMetrics();
totalWidth = fm.stringWidth(msg);
showX = maxWidth - totalWidth;
ascent = fm.getMaxAscent();
showY = showY + descent + ascent + leading;
descent = fm.getMaxDescent();
leading = fm.getLeading();
g.drawString(msg, showX, showY);
}
}
}
package duomeiti;
import javax.swing.*;
import java.awt.*;
public class ManageFonts {
private JFrame jf;
private FontsCanvas palette; //可以显示多种文字的画布
public ManageFonts(){
jf = new JFrame("自行管理字体示例");
palette = new FontsCanvas();
jf.add(palette);
jf.setSize(500, 400);
jf.setLocation(300, 200);
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public static void main(String[] args) {
new ManageFonts();
}
}
5. 字体的特效显示
例5.1 字体特效显示示例。
package duomeiti;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Timer;
import java.util.TimerTask;
import javax.swing.*;
public class LightingLiteral implements ActionListener {
String title = "光照文字"; //显示的文字
Font myFont = new Font("宋体",Font.BOLD,48); //显示的字体
JPanel palette;
JFrame jf;
JButton startBtn;
Container con;
Timer myTimer;
Refresh task;
boolean startFlag;
public LightingLiteral(){
jf = new JFrame(title);
palette = new JPanel();
startBtn = new JButton("开始");
startFlag = true;
startBtn.addActionListener(this);
con = jf.getContentPane();
con.add(palette, BorderLayout.CENTER);
con.add(startBtn, BorderLayout.NORTH);
jf.setSize(500, 400);
jf.setLocation(300, 200);
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void actionPerformed(ActionEvent e) {
if(startFlag){
myTimer = new Timer();
task = new Refresh();
myTimer.schedule(task, 50, 50); //启动定时器，时间间隔为50毫秒
startBtn.setText("停止");
}else{
myTimer.cancel();
myTimer = null;
task = null;
startBtn.setText("开始");
}
startFlag = !startFlag;
}
//用定时器来绘图
class Refresh extends TimerTask{
int pos = 0;
int blink_width = 20; //光条的宽度
Graphics g = palette.getGraphics(); //注意画笔的获取方式
FontMetrics myFM = g.getFontMetrics(myFont);
int height = myFM.getHeight(); //计算文字的高度
int top = myFM.getAscent();
int width = myFM.stringWidth(title);
public Refresh(){
g.setFont(myFont);
}
public void run() {
g.setColor(Color.blue);
g.drawString(title, 0, top); //第一遍显示
g.clipRect(pos, 0, blink_width, height); //设置裁剪区域
g.setColor(Color.yellow);
g.drawString(title, 0, top); //第二遍显示，它只会显示在裁剪区域中
pos = (pos + 5) % width; //移动裁剪区域的位置
g.setClip(null); //让裁剪区域失效，准备重新绘制蓝色文字
}
}
public static void main(String[] args) {
new LightingLiteral();
}
}
时间： 2024-10-10 14:46:08