JProgressBarpb=progressBars[i];
if(i==0){
pb.setStringPainted(true);
pb.setString("CustomString");
}
if(i==1){
pb.setOrientation(JProgressBar.VERTICAL);
pb.setForeground(Color.yellow);
pb.setMaximum(1000);
pb.setValue(50);
pb.setBorder(
BorderFactory.createRaisedBevelBorder());
}
if(i==2){
pb.setForeground(Color.blue);
pb.setBorderPainted(false);
pb.setValue(50);
pb.setStringPainted(true);
}
if(i==3){
pb.setOrientation(JProgressBar.VERTICAL);
pb.setForeground(Color.red);
pb.setValue(90);
pb.setStringPainted(true);
pb.setBorder(
BorderFactory.createEtchedBorder());
}
contentPane.add(pb);
}
}
}
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。
11.1.1进度条与线程
例11-2使用JProgressBar
importjavax.swing.*;
importjava.awt.*;
importjava.awt.event.*;
publicclassTestextendsJApplet{
privateJProgressBarprogressBar=newJProgressBar();
privateJButtonstartButton=newJButton("start");
publicvoidinit(){
ContainercontentPane=getContentPane();
contentPane.setLayout(newFlowLayout());
contentPane.add(startButton);
contentPane.add(progressBar);
progressBar.setStringPainted(true);
startButton.addActionListener(newActionListener(){
publicvoidactionPerformed(ActionEvente){
(newUpdateThread()).start();
}
});
}
classUpdateThreadextendsThread{
Runnableupdate,finish;
intvalue,min,max,increment;
publicUpdateThread(){
max=progressBar.getMaximum();
min=progressBar.getMinimum();
update=newRunnable(){
publicvoidrun(){
value=progressBar.getValue()+increment;
updateProgressBar(value);
}
};
finish=newRunnable(){
publicvoidrun(){
updateProgressBar(min);
}
};
}
publicvoidrun(){
startButton.setEnabled(false);
while(value+increment<=max){
simulateTimeConsumingActivity();
SwingUtilities.invokeLater(update);
}
SwingUtilities.invokeLater(finish);
startButton.setEnabled(true);
}
privatevoidupdateProgressBar(intvalue){
progressBar.setValue(value);
}
privatevoidsimulateTimeConsumingActivity(){
try{
Thread.currentThread().sleep(1000);
increment=(max-min)/10;
}
catch(InterruptedExceptione){
e.printStackTrace();
}
}
}
}
11.1.2JProgressBar属性
11.1.3JProgressBar事件
例11-3监视一个进度条的值
importjavax.swing.*;
importjavax.swing.event.*;
importjava.awt.*;
importjava.awt.event.*;
publicclassTestextendsJApplet{
privateJProgressBarpb=newJProgressBar();
publicvoidinit(){
ContainercontentPane=getContentPane();
finalJButtonstartButton=newJButton("start");
contentPane.setLayout(newFlowLayout());
contentPane.add(startButton);
contentPane.add(pb);
startButton.addActionListener(newActionListener(){
publicvoidactionPerformed(ActionEvente){
(newGetInfoThread(pb)).start();
}
});
pb.addChangeListener(newChangeListener(){
publicvoidstateChanged(ChangeEvente){
intmin=pb.getMinimum(),max=pb.getMaximum();
intvalue=pb.getValue();
showStatus("Min:
"+min+",Max:
"+max+
",Value:
"+value);
}
});
}
}
classGetInfoThreadextendsThread{
Runnableupdate,finish;
JProgressBarpb;
intvalue,min,max,increment;
publicGetInfoThread(JProgressBarprogressBar){
pb=progressBar;
max=pb.getMaximum();
min=pb.getMinimum();
update=newRunnable(){
publicvoidrun(){
value=pb.getValue()+increment;
pb.setValue(value);
}
};
finish=newRunnable(){
publicvoidrun(){
value=min;
pb.setValue(value);
}
};
}
publicvoidrun(){
while(value+increment<=max){
simulateTimeConsumingActivity();
SwingUtilities.invokeLater(update);
}
SwingUtilities.invokeLater(finish);
}
privatevoidsimulateTimeConsumingActivity(){
try{
Thread.currentThread().sleep(1000);
increment=(max-min)/10;
}
catch(InterruptedExceptione){
e.printStackTrace();
}
}
}
11.1.4JProgressBar类总结
11.1.5AWT兼容
11.2JSlider
例11-4一个简单的JSlider例子
importjava.awt.*;
importjava.awt.event.*;
importjavax.swing.*;
importjava.util.*;
publicclassTestextendsJApplet{
publicvoidinit(){
ContainercontentPane=getContentPane();
JSliderslider=newJSlider();
contentPane.add(slider,BorderLayout.NORTH);
}
}
11.2.1填充的滑杆
例11-5一个填充的滑杆
importjava.awt.*;
importjava.awt.event.*;
importjavax.swing.*;
publicclassTestextendsJApplet{
publicTest(){
ContainercontentPane=getContentPane();
JSliderslider=newJSlider();
slider.putClientProperty("JSlider.isFilled",Boolean.TRUE);
contentPane.add(slider,BorderLayout.NORTH);
}
}
11.2.2滑杆间隔标记
例11-6显示滑杆的间隔标记
importjava.awt.*;
importjava.awt.event.*;
importjavax.swing.*;
importjava.util.*;
publicclassTestextendsJApplet{
publicvoidinit(){
ContainercontentPane=getContentPane();
JSliderslider=newJSlider();
JPanelcontrolPanel=newControlPanel(slider);
contentPane.setLayout(newBorderLayout(0,40));
contentPane.add(controlPanel,BorderLayout.NORTH);
contentPane.add(slider,BorderLayout.CENTER);
}
classControlPanelextendsJPanel{
publicControlPanel(finalJSliderslider){
JCheckBoxpaintTicks=newJCheckBox("PaintTicks");
JComboBoxminorSpacing=newJComboBox(),
majorSpacing=newJComboBox();
minorSpacing.addItem("0");
minorSpacing.addItem("3");
minorSpacing.addItem("5");
minorSpacing.addItem("10");
minorSpacing.addItem("20");
majorSpacing.addItem("0");
majorSpacing.addItem("3");
majorSpacing.addItem("5");
majorSpacing.addItem("10");
majorSpacing.addItem("20");
add(paintTicks);
add(newJLabel("MinorTickSpacing:
"));
add(minorSpacing);
add(newJLabel("MajorTickSpacing:
"));
add(majorSpacing);
paintTicks.addActionListener(newActionListener(){
publicvoidactionPerformed(ActionEvente){
JCheckBoxcb=(JCheckBox)e.getSource();
slider.setPaintTicks(cb.isSelected());
slider.repaint();
}
});
minorSpacing.addItemListener(newItemListener(){
publicvoiditemStateChanged(ItemEvente){
JComboBoxcb=(JComboBox)e.getSource();
intspacing=Integer.parseInt(
(String)cb.getSelectedItem());
slider.setMinorTickSpacing(spacing);
slider.revalidate();
}
});
majorSpacing.addItemListener(newItemListener(){
publicvoiditemStateChanged(ItemEvente){
JComboBoxcb=(JComboBox)e.getSource();
intspacing=Integer.parseInt(
(String)cb.getSelectedItem());
slider.setMajorTickSpacing(spacing);
slider.revalidate();
}
});
}
}
}
11.2.3滑杆标签
例11-7显示缺省的JSlider标签
importjava.awt.*;
importjava.awt.event.*;
importjavax.swing.*;
publicclassTestextendsJApplet{
publicTest(){
ContainercontentPane=getContentPane();
JSliderslider=newJSlider();
slider.setPaintLabels(true);
slider.setMajorTickSpacing(20);
contentPane.add(slider,BorderLayout.NORTH);
}
}
例11-8定制滑杆标签
importjava.util.*;
importjava.awt.*;
importjava.awt.event.*;
importjavax.swing.*;
publicclassTestextendsJApplet{
publicTest(){
ContainercontentPane=getContentPane();
JSliderslider=newJSlider();
Icon[]icons={
newImageIcon("basketball.gif"),
newImageIcon("baseball.gif"),
newImageIcon("soccer.gif"),
newImageIcon("clipboard.gif"),
newImageIcon("filmstrip.gif"),
newImageIcon("crab.gif"),
};
Hashtabletable=newHashtable();
for(inti=0,loc=0;itable.put(newInteger(loc),
newJLabel(Integer.toString(loc),
icons[i],
JLabel.LEFT));
}
slider.setLabelTable(table);
slider.setPaintLabels(true);
slider.setMajorTickSpacing(20);
contentPane.add(slider,BorderLayout.NORTH);
}
}
11.2.4反转滑杆值
例11-9中列出图11-10中示出的小应用程序的代码
importjava.awt.*;
importjava.awt.event.*;
importjavax.swing.*;
publicclassTestextendsJApplet{
privateJCheckBoxcheckBox=newJCheckBox("Invert");
privateJSlider[]sliders={newJSlider(),
newJSlider(JSlider.VERTICAL)};
publicTest(){
ContainercontentPane=getContentPane();
contentPane.setLayout(newFlowLayout());
contentPane.add(checkBox);
for(inti=0;isliders[i].setPaintLabels(true);
sliders[i].setMajorTickSpacing(20);
contentPane.add(sliders[i]);
}
checkBox.addActionListener(newActionListener(){
publicvoidactionPerformed(ActionEvente){
for(inti=0;isliders[i].setInverted(checkBox.isSelected());
}
});
}
}
11.2.5滑杆的外延值
例11-10设置一个滑杆的外延值
importjava.awt.*;
importjava.awt.event.*;
importjavax.swing.*;
importjavax.swing.event.*;
publicclassTestextendsJApplet{
publicTest(){
ContainercontentPane=getContentPane();
JSliderslider=newJSlider();
JPanelcontrolPanel=newControlPanel(slider);
contentPane.add(controlPanel,BorderLayout.NORTH);
contentPane.add(slider,BorderLayout.SOUTH);
slider.addChangeListener(newChangeListener(){
publicvoidstateChanged(ChangeEvente){
JSliders=(JSlider)e.getSource();
showStatus("Min:
"+s.getMinimum()+
",Max:
"+s.get