问题
i've discovered this test project from Oracle site because i want to add a circular progress bar in my project.
I'm developing the application with Netbeans, and when i start the application, the JPanel where the circle should be.... disappaer.
I've removed all the code that is not useful to solve this problem and i've got this code:
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.beans.PropertyChangeEvent;
import javax.swing.*;
import javax.swing.plaf.LayerUI;
public class Loading_Test extends javax.swing.JFrame
{
static final WaitLayerUI layerUI = new WaitLayerUI();
public Loading_Test()
{
JPanel panel = new JPanel();
JLayer<JPanel> jlayer = new JLayer<>(panel, layerUI);
add(jlayer);
initComponents();
}
@SuppressWarnings("unchecked")
private void initComponents() {
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 400, Short.MAX_VALUE)
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 300, Short.MAX_VALUE)
);
pack();
}
public static void main(String args[])
{
java.awt.EventQueue.invokeLater(new Runnable()
{
@Override
public void run()
{
JFrame frame = new Loading_Test();
frame.setVisible(true);
layerUI.start();
}
});
}
}
class WaitLayerUI extends LayerUI<JPanel> implements ActionListener
{
private boolean mIsRunning;
private boolean mIsFadingOut;
private Timer mTimer;
private int mAngle;
private int mFadeCount;
private int mFadeLimit = 15;
@Override
public void paint(Graphics g, JComponent c)
{
int w = c.getWidth();
int h = c.getHeight();
// Paint the view.
super.paint(g, c);
if (!mIsRunning)
{
return;
}
Graphics2D g2 = (Graphics2D) g.create();
float fade = (float) mFadeCount / (float) mFadeLimit;
// Gray it out.
Composite urComposite = g2.getComposite();
g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, .5f * fade));
g2.fillRect(0, 0, w, h);
g2.setComposite(urComposite);
// Paint the wait indicator.
int s = Math.min(w, h) / 5;
int cx = w / 2;
int cy = h / 2;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setStroke(new BasicStroke(s / 4, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
g2.setPaint(Color.white);
g2.rotate(Math.PI * mAngle / 180, cx, cy);
for (int i = 0; i < 12; i++)
{
float scale = (11.0f - (float) i) / 11.0f;
g2.drawLine(cx + s, cy, cx + s * 2, cy);
g2.rotate(-Math.PI / 6, cx, cy);
g2.setComposite(AlphaComposite.getInstance(
AlphaComposite.SRC_OVER, scale * fade));
}
g2.dispose();
}
@Override
public void actionPerformed(ActionEvent e)
{
if (mIsRunning)
{
firePropertyChange("tick", 0, 1);
mAngle += 3;
if (mAngle >= 360)
{
mAngle = 0;
}
if (mIsFadingOut)
{
if (--mFadeCount == 0)
{
mIsRunning = false;
mTimer.stop();
}
}
else if (mFadeCount < mFadeLimit)
{
mFadeCount++;
}
}
}
public void start()
{
if (mIsRunning)
{
return;
}
// Run a thread for animation.
mIsRunning = true;
mIsFadingOut = false;
mFadeCount = 0;
int fps = 24;
int tick = 1000 / fps;
mTimer = new Timer(tick, this);
mTimer.start();
}
public void stop()
{
mIsFadingOut = true;
}
@Override
public void applyPropertyChange(PropertyChangeEvent pce, JLayer l)
{
if ("tick".equals(pce.getPropertyName()))
{
l.repaint();
}
}
}
If you run this code "as is", you should have the same my problem, the JPanel is not shown.
But i've discovered that if i remove the layout-related lines (27~36) the progress bar starts to work.
You also have to set manually the windows size adding
setSize(300, 300);
after
pack();
Because the layout-lines are automatically generated by Netbeans, i'm trying to understand how to solve this problem, because this particular lines of code are blocked for editing by Netbeans Editor.
回答1:
I've lost one day and it still not working.... I'll use an animated gif on JLabel.... End of story!
@Robin has important info, and seems like as you limited by usage of GuiBulder..., then I'm don't want to comment something, result is
from little bit modified code
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.beans.PropertyChangeEvent;
import javax.swing.*;
import javax.swing.plaf.LayerUI;
public class Loading_Test {
static final WaitLayerUI layerUI = new WaitLayerUI();
JFrame frame = new JFrame("JLayer With Animated Gif");
public Loading_Test() {
JPanel panel = new JPanel() {
@Override
public Dimension getPreferredSize() {
return new Dimension(400, 300);
}
};
JLayer<JPanel> jlayer = new JLayer<>(panel, layerUI);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(jlayer);
frame.pack();
frame.setVisible(true);
layerUI.start();
}
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
Loading_Test loading_Test = new Loading_Test();
}
});
}
}
class WaitLayerUI extends LayerUI<JPanel> implements ActionListener {
private boolean mIsRunning;
private boolean mIsFadingOut;
private Timer mTimer;
private int mAngle;
private int mFadeCount;
private int mFadeLimit = 15;
@Override
public void paint(Graphics g, JComponent c) {
int w = c.getWidth();
int h = c.getHeight();
super.paint(g, c); // Paint the view.
if (!mIsRunning) {
return;
}
Graphics2D g2 = (Graphics2D) g.create();
float fade = (float) mFadeCount / (float) mFadeLimit;
Composite urComposite = g2.getComposite(); // Gray it out.
g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, .5f * fade));
g2.fillRect(0, 0, w, h);
g2.setComposite(urComposite);
int s = Math.min(w, h) / 5;// Paint the wait indicator.
int cx = w / 2;
int cy = h / 2;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setStroke(new BasicStroke(s / 4, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
g2.setPaint(Color.white);
g2.rotate(Math.PI * mAngle / 180, cx, cy);
for (int i = 0; i < 12; i++) {
float scale = (11.0f - (float) i) / 11.0f;
g2.drawLine(cx + s, cy, cx + s * 2, cy);
g2.rotate(-Math.PI / 6, cx, cy);
g2.setComposite(AlphaComposite.getInstance(
AlphaComposite.SRC_OVER, scale * fade));
}
g2.dispose();
}
@Override
public void actionPerformed(ActionEvent e) {
if (mIsRunning) {
firePropertyChange("tick", 0, 1);
mAngle += 3;
if (mAngle >= 360) {
mAngle = 0;
}
if (mIsFadingOut) {
if (--mFadeCount == 0) {
mIsRunning = false;
mTimer.stop();
}
} else if (mFadeCount < mFadeLimit) {
mFadeCount++;
}
}
}
public void start() {
if (mIsRunning) {
return;
}
mIsRunning = true;// Run a thread for animation.
mIsFadingOut = false;
mFadeCount = 0;
int fps = 24;
int tick = 1000 / fps;
mTimer = new Timer(tick, this);
mTimer.start();
}
public void stop() {
mIsFadingOut = true;
}
@Override
public void applyPropertyChange(PropertyChangeEvent pce, JLayer l) {
if ("tick".equals(pce.getPropertyName())) {
l.repaint();
}
}
}
have to add two
JButtons
, one for start and second for stop (show and hide animated Gig)don't forger that
JPanel
has implementedFlowLayout
, that pretty acceptingPreferredSize
came from its childs,
回答2:
Found a better simple (and working) solution with Swing Components Extension by SwingLabs
JXBusyLabel
There is a fully integrating plugin with NetBeans for its editor, so is very simple to use
回答3:
It seems from your question and comments you are having problems implementing the JLayer
in Netbeans, I'd suggest then rather going for a CardLayout which will allow you to switch between your normal JPanel
and the one with the spinner.
Here is a simple tutorial: CardLayout With Netbeans
来源:https://stackoverflow.com/questions/11846589/circular-progress-bar-for-java-swing-not-working