进度条的使用

每隔一秒钟,进度条的使用

java 代码

package example;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseMotionAdapter;

import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
import javax.swing.Timer;

public class GlassExample extends JFrame {
  JPanel glass = new JPanel(new GridLayout(0, 1));
  JProgressBar waiter = new JProgressBar(0, 100);
  Timer timer;

  public GlassExample( ) {
    super("GlassPane Demo");
    setSize(500, 300);
    setDefaultCloseOperation(EXIT_ON_CLOSE);

    // Set up the glass pane with a little message and a progress bar.
    JPanel controlPane = new JPanel(new GridLayout(2,1));
    controlPane.setOpaque(false);
    controlPane.add(new JLabel("Please wait..."));
    controlPane.add(waiter);
    glass.setOpaque(false);
    glass.add(new JLabel( )); // Padding...
    glass.add(new JLabel( ));
    glass.add(controlPane);
    glass.add(new JLabel( ));
    glass.add(new JLabel( ));
    glass.addMouseListener(new MouseAdapter( ) {});
    glass.addMouseMotionListener(new MouseMotionAdapter( ) {});
    setGlassPane(glass);

    // Now set up a few buttons and images for the main application.
    JPanel mainPane = new JPanel( );
    mainPane.setBackground(Color.white);
    JButton redB = new JButton("Red");
    JButton blueB = new JButton("Blue");
    JButton greenB = new JButton("Green");
    mainPane.add(redB);
    mainPane.add(greenB);
    mainPane.add(blueB);
    mainPane.add(new JLabel(new ImageIcon("oreilly.gif")));

    // Attach the pop-up debugger to the main app buttons so you
    // see the effect of making a glass pane visible.
    PopupDebugger pd = new PopupDebugger(this);
    redB.addActionListener(pd);
    greenB.addActionListener(pd);
    blueB.addActionListener(pd);

    // And last but not least, our button to launch the glass pane
    JButton startB = new JButton("Start the big operation!");
    startB.addActionListener(new ActionListener( ) {
        public void actionPerformed(java.awt.event.ActionEvent A) {
          glass.setVisible(true);
          startTimer( );
        }
      });

    Container contentPane = getContentPane( );
    contentPane.add(mainPane, BorderLayout.CENTER);
    contentPane.add(startB, BorderLayout.SOUTH);
  }

  // A quick method to start up a 10-second timer and update the progress bar
  public void startTimer( ) {
    if (timer == null) {
      timer = new Timer(1000, new ActionListener( ) {
          int progress = 0;
          public void actionPerformed(ActionEvent A) {
            progress += 1;
            waiter.setValue(progress);

            // Once we hit 100%, remove the glass pane and reset the progress bar
            // stuff.
            if (progress >= 100) {
              progress = 0;
              timer.stop( );
              glass.setVisible(false);
              waiter.setValue(0);
            }
          }
        });
    }
    if (timer.isRunning( )) {
      timer.stop( );
    }
    timer.start( );
  }

  // A graphical debugger that pops up whenever a button is pressed
  public class PopupDebugger implements ActionListener {
    private JFrame parent;
    public PopupDebugger(JFrame f) {
      parent = f;
    }
    public void actionPerformed(ActionEvent ae) {
      JOptionPane.showMessageDialog(parent, ae.getActionCommand( ));
    }
  }

  public static void main(String[] args) {
    GlassExample ge = new GlassExample( );
    ge.setVisible(true);
  }
}