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<SCRIPT LANGUAGE="JavaScript" SRC="/-fs0/sys/pop-up.js"></SCRIPT><SCRIPT LANGUAGE="JavaScript" SRC="/-fs0/sys/pop-up-all.js"></SCRIPT><html><head><title>易都网--Java 2 图形设计卷Ⅱ：SWING</title><LINK rel="stylesheet" href="../../../_public/javaa.css"><meta http-equiv="Content-Type" content="text/html; charset=GBK"><script language="JavaScript" src="../../../_public/javaa.js"></script><meta name="keywords" content="Java,JSP,ASP,PHP,J2EE,EJB,JavaScript,C/C++,ASM,CSS,HTML,XML,网络安全,MySQL,ACCESS"></head><body bgcolor="#FFFFFF"><table border=0 cellpadding=0 cellspacing=0 width="100%"> <tbody> <script language="javascript">print2()</script> <tr> <td width="100%"> <table bgcolor=#EEEEEE border=0 cellpadding=3 cellspacing=0 width="100%"> <tbody> <tr> <td class=f1 id=thetd width="100%"> <p>[<a href="index.html" target="_self">目录</a>][<a href="s10.htm">上一页</a>][<a href="s12.htm">下一页</a>]</p> <p align="center"><b>第11章 进度条、滑杆和分隔条</b></p> <p> 本章介绍三个Swing组件：JProgressBar、JSlider和JSeparator。<br> 人们经常用进度条反映耗时任务已完成的百分比，本章将提供这样一个例子。但是，用ProgressMonitor和ProgressMonitorInputStream实用工具来反映一个任务的进度信息通常会更容易。“进度监控”小节中讨论了ProgressMonitor和ProgressMonitorInputStream实用工具。<br> JProgressBar和JSlider与JSeparator一样，用来描述一个介于最小值和最大值之间的值。因此，与JProgressBar和JSlider相关的模型是BoundedRangeModel接口的一个实现。<br> JSeparator是绘制一条蚀刻线的组件，它把逻辑上相关的组件分隔在一组，JSeparator组件可水平地垂直地放置。 </p> <p> <b>11.1 JProgressBar</b></p> <p> JProgressBar是一个简单的组件，它一般是一种颜色部分或完全填充的矩形。缺省情况下，进度条配备了一个凹陷的边框，并水平放置。<br> 进度条还可以选择显示一个字符串，这个字符串在进度条矩形的中央位置上显示。这个字符串缺省时为耗时任务已完成的百分比。这个字符串可用JProgressBar.setString方法定制。<br> 图11-1中示出的小应用程序创建了不同配置的进度条。 <br> 例11-1列出了图11-1中示出的小应用程序的代码。</p> <p align="center"><b>例11-1 各种配置的进度条</b></p> <hr size="1" noshade> import javax.swing.*;<br> import java.awt.*;<br> import java.awt.event.*; <p>public class Test extends JApplet {<br> private JProgressBar[] progressBars = {<br> new JProgressBar(),<br> new JProgressBar(),<br> new JProgressBar(),<br> new JProgressBar()<br> };</p> <p> public void init() {<br> Container contentPane = getContentPane();</p> <p> contentPane.setLayout(new FlowLayout());</p> <p> for(int i=0; i < progressBars.length; ++i) {<br> JProgressBar pb = progressBars[i];</p> <p> if(i == 0) {<br> pb.setStringPainted(true);<br> pb.setString("Custom String");<br> }<br> if(i == 1) {<br> pb.setOrientation(JProgressBar.VERTICAL);<br> pb.setForeground(Color.yellow);<br> pb.setMaximum(1000);<br> pb.setValue(50);<br> pb.setBorder(<br> BorderFactory.createRaisedBevelBorder());<br> }<br> if(i == 2) {<br> pb.setForeground(Color.blue);<br> pb.setBorderPainted(false);<br> pb.setValue(50);<br> pb.setStringPainted(true);<br> }<br> if(i == 3) {<br> pb.setOrientation(JProgressBar.VERTICAL);<br> pb.setForeground(Color.red);<br> pb.setValue(90);<br> pb.setStringPainted(true);<br> pb.setBorder(<br> BorderFactory.createEtchedBorder());<br> }<br> contentPane.add(pb);<br> }<br> }<br> }</p> <hr size="1" noshade> 这个小应用程序创建了一组进度条，并为每个进度条设置了各种不同的属性，从而产生了图11-1中示出的各种不同配置。<br> <p> <b>11.1.1 进度条与线程</b></p> <p> </p> <p align="center"><b>例11-2 使用JProgressBar</b></p> <hr noshade size="1"> import javax.swing.*;<br> import java.awt.*;<br> import java.awt.event.*; <p>public class Test extends JApplet {<br> private JProgressBar progressBar = new JProgressBar();<br> private JButton startButton = new JButton("start");</p> <p> public void init() {<br> Container contentPane = getContentPane();</p> <p> contentPane.setLayout(new FlowLayout());<br> contentPane.add(startButton);<br> contentPane.add(progressBar);</p> <p> progressBar.setStringPainted(true);</p> <p> startButton.addActionListener(new ActionListener() {<br> public void actionPerformed(ActionEvent e) {<br> (new UpdateThread()).start();<br> }<br> });<br> }<br> class UpdateThread extends Thread {<br> Runnable update, finish;<br> int value, min, max, increment;</p> <p> public UpdateThread() {<br> max = progressBar.getMaximum(); <br> min = progressBar.getMinimum();</p> <p> update = new Runnable() {<br> public void run() {<br> value = progressBar.getValue() + increment;<br> updateProgressBar(value);<br> }<br> };<br> finish = new Runnable() {<br> public void run() {<br> updateProgressBar(min);<br> }<br> };<br> }<br> public void run() {<br> startButton.setEnabled(false);</p> <p> while(value + increment <= max) {<br> simulateTimeConsumingActivity();<br> SwingUtilities.invokeLater(update);<br> }<br> SwingUtilities.invokeLater(finish);<br> startButton.setEnabled(true);<br> }<br> private void updateProgressBar(int value) {<br> progressBar.setValue(value);<br> }<br> private void simulateTimeConsumingActivity() {<br> try {<br> Thread.currentThread().sleep(1000);<br> increment = (max - min) / 10;<br> }<br> catch(InterruptedException e) {<br> e.printStackTrace();<br> }<br> }<br> }<br> }</p> <hr size="1" noshade> <p> 11.1.2 JProgressBar属性</p> <p> </p> <p> 11.1.3 JProgressBar事件</p> <p> </p> <p align="center"><b>例11-3 监视一个进度条的值</b></p> <hr noshade size="1"> import javax.swing.*;<br> import javax.swing.event.*;<br> import java.awt.*;<br> import java.awt.event.*; <p>public class Test extends JApplet {<br> private JProgressBar pb = new JProgressBar();</p> <p> public void init() {<br> Container contentPane = getContentPane();<br> final JButton startButton = new JButton("start");</p> <p> contentPane.setLayout(new FlowLayout());<br> contentPane.add(startButton);<br> contentPane.add(pb);</p> <p> startButton.addActionListener(new ActionListener() {<br> public void actionPerformed(ActionEvent e) {<br> (new GetInfoThread(pb)).start();<br> }<br> });<br> pb.addChangeListener(new ChangeListener() {<br> public void stateChanged(ChangeEvent e) {<br> int min = pb.getMinimum(), max = pb.getMaximum();<br> int value = pb.getValue();</p> <p> showStatus("Min: " + min + ", Max: " + max +<br> ", Value: " + value);<br> }<br> });<br> }<br> }<br> class GetInfoThread extends Thread {<br> Runnable update, finish;<br> JProgressBar pb;<br> int value, min, max, increment;</p> <p> public GetInfoThread(JProgressBar progressBar) {<br> pb = progressBar;</p> <p> max = pb.getMaximum(); <br> min = pb.getMinimum();</p> <p> update = new Runnable() {<br> public void run() {<br> value = pb.getValue() + increment;<br> pb.setValue(value);<br> }<br> };<br> finish = new Runnable() {<br> public void run() {<br> value = min;<br> pb.setValue(value);<br> }<br> };<br> }<br> public void run() {<br> while(value + increment <= max) {<br> simulateTimeConsumingActivity();<br> SwingUtilities.invokeLater(update);<br> }<br> SwingUtilities.invokeLater(finish);<br> }<br> private void simulateTimeConsumingActivity() {<br> try {<br> Thread.currentThread().sleep(1000);<br> increment = (max - min) / 10;<br> }<br> catch(InterruptedException e) {<br> e.printStackTrace();<br> }<br> }<br> }</p> <hr size="1" noshade> <p> 11.1.4 JProgressBar类总结</p> <p> </p> <p> 11.1.5 AWT兼容</p> <p> </p> <p> 11.2 JSlider</p> <p> </p> <p align="center"><b>例11-4 一个简单的JSlider例子</b></p> <hr noshade size="1"> import java.awt.*;<br> import java.awt.event.*;<br> import javax.swing.*;<br> import java.util.*; <p>public class Test extends JApplet {<br> public void init() {<br> Container contentPane = getContentPane();<br> JSlider slider = new JSlider();</p> <p> contentPane.add(slider, BorderLayout.NORTH);<br> }<br> }</p> <hr size="1" noshade> <p> 11.2.1 填充的滑杆</p> <p> </p> <p align="center"><b>例11-5 一个填充的滑杆</b></p> <hr noshade size="1"> import java.awt.*;<br> import java.awt.event.*;<br> import javax.swing.*; <p>public class Test extends JApplet {<br> public Test() {<br> Container contentPane = getContentPane();<br> JSlider slider = new JSlider();</p> <p> slider.putClientProperty("JSlider.isFilled",Boolean.TRUE);</p> <p> contentPane.add(slider, BorderLayout.NORTH);<br> }<br> }</p> <hr size="1" noshade> <p> 11.2.2 滑杆间隔标记</p> <p> </p> <p align="center"><b>例11-6 显示滑杆的间隔标记</b></p> <hr noshade size="1"> import java.awt.*;<br> import java.awt.event.*;<br> import javax.swing.*;<br> import java.util.*; <p>public class Test extends JApplet {<br> public void init() {<br> Container contentPane = getContentPane();<br> JSlider slider = new JSlider();<br> JPanel controlPanel = new ControlPanel(slider);</p> <p> contentPane.setLayout(new BorderLayout(0,40));<br> contentPane.add(controlPanel, BorderLayout.NORTH);<br> contentPane.add(slider, BorderLayout.CENTER);<br> }<br> class ControlPanel extends JPanel {<br> public ControlPanel(final JSlider slider) {<br> JCheckBox paintTicks = new JCheckBox("Paint Ticks");<br> JComboBox minorSpacing = new JComboBox(),<br> majorSpacing = new JComboBox();</p> <p> minorSpacing.addItem("0");<br> minorSpacing.addItem("3");<br> minorSpacing.addItem("5");<br> minorSpacing.addItem("10");<br> minorSpacing.addItem("20");</p> <p> majorSpacing.addItem("0");<br> majorSpacing.addItem("3");<br> majorSpacing.addItem("5");<br> majorSpacing.addItem("10");<br> majorSpacing.addItem("20");</p> <p> add(paintTicks);<br> add(new JLabel("Minor Tick Spacing:"));<br> add(minorSpacing);<br> add(new JLabel("Major Tick Spacing:"));<br> add(majorSpacing);</p> <p> paintTicks.addActionListener(new ActionListener() {<br> public void actionPerformed(ActionEvent e) {<br> JCheckBox cb = (JCheckBox)e.getSource();<br> slider.setPaintTicks(cb.isSelected());<br> slider.repaint();<br> }<br> });<br> minorSpacing.addItemListener(new ItemListener() {<br> public void itemStateChanged(ItemEvent e) {<br> JComboBox cb = (JComboBox)e.getSource();<br> int spacing = Integer.parseInt(<br> (String)cb.getSelectedItem());</p> <p> slider.setMinorTickSpacing(spacing);<br> slider.revalidate();<br> }<br> });<br> majorSpacing.addItemListener(new ItemListener() {<br> public void itemStateChanged(ItemEvent e) {<br> JComboBox cb = (JComboBox)e.getSource();<br> int spacing = Integer.parseInt(<br>⌨️ 快捷键说明
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