Egge at 21:33, 12 October 2008

2008-10-12T21:33:51Z

← Older revision		Revision as of 21:33, 12 October 2008
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	Here's a basic example of how to use a SwingWorker for a long running background task.		Here's a basic example of how to use a SwingWorker for a long running background task.

	Idle		=== Idle ===

	[[Image:lucky1.PNG]]		[[Image:lucky1.PNG]]

	Running		=== Running ===

	[[Image:lucky2.PNG]]		[[Image:lucky2.PNG]]

Egge: New page: Here's a basic example of how to use a SwingWorker for a long running background task. Idle Image:lucky1.PNG Running Image:lucky2.PNG package swingworker; ...

2008-10-10T06:53:50Z

New page: Here's a basic example of how to use a SwingWorker for a long running background task. Idle Image:lucky1.PNG Running Image:lucky2.PNG <geshi lang="java5"> package swingworker; ...

New page

Here's a basic example of how to use a SwingWorker for a long running background task.

Idle
[[Image:lucky1.PNG]]

Running
[[Image:lucky2.PNG]]

<geshi lang="java5">
package swingworker;

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;

import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;

import org.jdesktop.swingworker.SwingWorker;

public class LuckyNumber extends JFrame implements ActionListener {
private static final long serialVersionUID = 4276832367310733568L;
private JLabel label;
private JButton cancel;
private JButton start;
private SwingWorker<?,?> worker;
private JTextField textField;

public LuckyNumber() {
JPanel panel = new JPanel();
panel.setLayout(new GridLayout(2, 1));

JPanel buttons = new JPanel(new FlowLayout());
start = new JButton("Start");
start.addActionListener(this);
start.setDefaultCapable(true);
buttons.add(start);
cancel = new JButton("Cancel");
cancel.setEnabled(false);
cancel.addActionListener(this);
buttons.add(cancel);
panel.add(buttons);

ImageIcon image;
if (getClass().getResourceAsStream("/swingworker/spinner.gif") != null)
image = new ImageIcon("swingworker/spinner.gif");
else
image = new ImageIcon("http://www.me.com/my/shared_1b/en/images/spinners/spinner_32px_f3f5f5.gif");

label = new JLabel(image);
JPanel answer = new JPanel(new GridLayout(1, 2));
textField = new JTextField("");
answer.add(textField);
answer.add(label);
label.setVisible(false);
panel.add(answer);

setTitle("Lucky number generator");
setPreferredSize(new Dimension(300, 100));
getContentPane().setLayout(new BorderLayout());
getContentPane().add(panel);

}

public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
LuckyNumber luckyNumber = new LuckyNumber();
luckyNumber.pack();
luckyNumber.setVisible(true);
luckyNumber.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
}
});
}

public void actionPerformed(ActionEvent e) {
if (e.getSource() == start) {
start.setEnabled(false);
textField.setText("");
worker = new NumberWorker();
worker.execute();
label.setVisible(true);
cancel.setEnabled(true);
} else if (e.getSource() == cancel) {
cancel();
}

}

@Override
public void dispose() {
cancel();
super.dispose();
}

private void cancel() {
start.setEnabled(true);
label.setVisible(false);
cancel.setEnabled(false);
if (worker != null) {
worker.cancel(true);
worker = null;
}

}

private class NumberWorker extends SwingWorker<String, Object> {

private Random r = new Random();

@Override
protected String doInBackground() throws Exception {
long s = System.currentTimeMillis();
while (System.currentTimeMillis() - s < 5000 && !Thread.currentThread().isInterrupted()) {
r.nextInt();
}
return String.valueOf(r.nextInt(10) + 1);
}

@Override
protected void done() {
try {
textField.setText(get());
LuckyNumber.this.worker = null;
LuckyNumber.this.cancel();
} catch (Exception ignore) {
}
}
}

}
</geshi>

[[Category:Java]]

SwingWorker Example - Revision history

Egge at 21:33, 12 October 2008

Egge: New page: Here's a basic example of how to use a SwingWorker for a long running background task. Idle Image:lucky1.PNG Running Image:lucky2.PNG package swingworker; ...