Java- How to Flash JPanel Window

问题

I have a JPanel window with a few things drawn on it. I am trying to figure out how I can flash the screen, like one simple flash, to get a users attention? I found a previous question on this but it did not work for what I am trying to do. I have a continuous loop that updates the screen based on a few variables. I would just like the screen to flash at a certain point and then go back to normal.

Thanks!

回答1:

You can use Trident to interpolate various properties in your class. Here is a demo that animates panel's background:

import java.awt.Color;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;

import org.pushingpixels.trident.Timeline;
import org.pushingpixels.trident.Timeline.RepeatBehavior;

public class TestPanel {
    private static void createAndShowGUI() {
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JPanel panel = new JPanel();
        panel.add(new JLabel("Some text"));

        frame.add(panel);
        frame.pack();
        frame.setVisible(true);

        final Timeline timeline = new Timeline(panel);
        timeline.addPropertyToInterpolate("background", panel.getBackground(),
                Color.red);
        timeline.setDuration(1000);

        timeline.playLoop(5, RepeatBehavior.REVERSE);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}

EDIT: comments to auto hide a popup

You can use timer to hide a popup, for example:

import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class TempPopup {

    public static void main(String[] args) {

        JOptionPane pane = new JOptionPane("Message",
                JOptionPane.INFORMATION_MESSAGE);
        final JDialog dialog = pane.createDialog(null, "Title");

        Timer timer = new Timer(2000, new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                dialog.setVisible(false);
                dialog.dispose();
            }
        });
        timer.setRepeats(false);
        timer.start();
        dialog.setVisible(true);
        dialog.dispose();
    }
}

回答2:

Use a glass pane component as in the sample demo below:

import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class Demo {
    public static void main(String[] args) {
        JFrame frame = new JFrame();
        final JPanel panel = new JPanel();
        frame.add(panel);

        JComponent flashPane = new JComponent() {
            @Override
            public void paint(Graphics g) {
                // Add code to draw whatever you want to grab attention here
                g.setColor(Color.CYAN);
                g.fillRect(0, 0, panel.getWidth(), panel.getHeight());
                super.paint(g);
            }
        };

        panel.getRootPane().setGlassPane(flashPane);
        frame.setBounds(0, 0, 200, 200);
        frame.setVisible(true);

        // Sample loop to flash every 2 seconds
        while(true) {
            try {
                Thread.sleep(2000);
                flashPane.setVisible(true);
                Thread.sleep(200);
                flashPane.setVisible(false);
            } catch(Exception ex) {
            }
        }
    }
}

回答3:

I'd suggest pseudo code like this:

if(your flash condition is true){
yourFrame.visible = False; // no longer display the frame.
Thread.sleep(500); // waits for half a second.
yourFrame.visible = True; // show the frame again.
}

You may want to validate your view (frame) after to make sure any changes that may of occurred in your model (variables etc) are reflected after the Thread wakes and the frame is displayed again.

来源：https://stackoverflow.com/questions/11745391/java-how-to-flash-jpanel-window