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Visualizza la versione completa : [Java] JProgressBar


albe99_03
25-08-2003, 10:38
Salve a tutti:)

vorrei creare una JProgressBar che parte quando lancio la mia applicazione, praticamente un preload..
qualcuno mi puo' segnalare esempi da scoppiazzare?

grazie come sempre..:D

Angelo1974
25-08-2003, 12:44
Questo esempio prelevato dalla sun dovrebbe aiutarti:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class ProgressBarDemo extends JFrame {
public final static int ONE_SECOND = 1000;

private JProgressBar progressBar;
private Timer timer;
private JButton startButton;
private LongTask task;
private JTextArea taskOutput;
private String newline = "\n";

public ProgressBarDemo() {
super("ProgressBarDemo");
task = new LongTask();

//Create the demo's UI.
startButton = new JButton("Start");
startButton.setActionCommand("start");
startButton.addActionListener(new ButtonListener());

progressBar = new JProgressBar(0, task.getLengthOfTask());
progressBar.setValue(0);
progressBar.setStringPainted(true);

taskOutput = new JTextArea(5, 20);
taskOutput.setMargin(new Insets(5,5,5,5));
taskOutput.setEditable(false);

JPanel panel = new JPanel();
panel.add(startButton);
panel.add(progressBar);

JPanel contentPane = new JPanel();
contentPane.setLayout(new BorderLayout());
contentPane.add(panel, BorderLayout.NORTH);
contentPane.add(new JScrollPane(taskOutput), BorderLayout.CENTER);
contentPane.setBorder(BorderFactory.createEmptyBor der(20, 20, 20, 20));
setContentPane(contentPane);

//Create a timer.
timer = new Timer(ONE_SECOND, new ActionListener() {
public void actionPerformed(ActionEvent evt) {
progressBar.setValue(task.getCurrent());
taskOutput.append(task.getMessage() + newline);
taskOutput.setCaretPosition(
taskOutput.getDocument().getLength());
if (task.done()) {
Toolkit.getDefaultToolkit().beep();
timer.stop();
startButton.setEnabled(true);
progressBar.setValue(progressBar.getMinimum());
}
}
});
}

/**
* The actionPerformed method in this class
* is called when the user presses the start button.
*/
class ButtonListener implements ActionListener {
public void actionPerformed(ActionEvent evt) {
startButton.setEnabled(false);
task.go();
timer.start();
}
}

public static void main(String[] args) {
JFrame frame = new ProgressBarDemo();
frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});

frame.pack();
frame.setVisible(true);
}
}
Cmq In questo indirizzo (http://java.sun.com/docs/books/tutorial/uiswing/components/progress.html) dovresti trovare tutti o buona parte degli esempi sulle ProgressBar
Ciaooooo:ciauz:

albe99_03
25-08-2003, 13:06
ottimo....grazie mille:)

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