This is my class which I found on the Internet. It was originally an applet but I don't want to use it as an applet so I changed some methods (such as init()
to a constructor).
However, it doesn't work. Would you please help me?
SignInFrame Frame:
public class SignInFrame extends javax.swing.JFrame {
Panel panel;
/** Creates new form SignInFrame */
public SignInFrame() {
initComponents();
}
public void init() {
getContentPane().add(panel = new Panel());
}
public void start() {
panel.start();
}
public void stop() {
panel.stop();
}
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new SignInFrame().setVisible(true);
}
});
}}
Panel Dialog:
package ClientGUI;
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GradientPaint;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.RenderingHints;
import java.awt.geom.GeneralPath;
import java.awt.image.BufferedImage;
/**
*
* @author ICC
*/
public class Panel extends javax.swing.JPanel implements Runnable{
private Thread thread;
private BufferedImage bimg;
private static final int NUMPTS = 6;
// solid line stoke
protected BasicStroke solid = new BasicStroke(10.0f,
BasicStroke.CAP_BUTT, BasicStroke.JOIN_ROUND);
// dashed line stroke
protected BasicStroke dashed = new BasicStroke(10.0f,
BasicStroke.CAP_BUTT, BasicStroke.JOIN_ROUND, 10, new float[] {5}, 0);
private float animpts[] = new float[NUMPTS * 2];
private float deltas[] = new float[NUMPTS * 2];
protected Paint fillPaint, drawPaint;
// indicates whether or not to fill shape
protected boolean doFill = true;
// indicates whether or not to draw shape
protected boolean doDraw = true;
protected GradientPaint gradient;
protected BasicStroke stroke;
public Panel() {
setBackground(Color.white);
gradient = new GradientPaint(0,0,Color.red,200,200,Color.yellow);
fillPaint = gradient;
drawPaint = Color.blue;
stroke = solid;
}
// generates new points for the path
public void animate(float[] pts, float[] deltas, int i, int limit) {
float newpt = pts[i] + deltas[i];
if (newpt <= 0) {
newpt = -newpt;
deltas[i] = (float) (Math.random() * 4.0 + 2.0);
} else if (newpt >= (float) limit) {
newpt = 2.0f * limit - newpt;
deltas[i] = - (float) (Math.random() * 4.0 + 2.0);
}
pts[i] = newpt;
}
/*
* generates random points with the specified surface width
* and height for the path
*/
public void reset(int w, int h) {
for (int i = 0; i < animpts.length; i += 2) {
animpts[i + 0] = (float) (Math.random() * w);
animpts[i + 1] = (float) (Math.random() * h);
deltas[i + 0] = (float) (Math.random() * 6.0 + 4.0);
deltas[i + 1] = (float) (Math.random() * 6.0 + 4.0);
if (animpts[i + 0] > w / 2.0f) {
deltas[i + 0] = -deltas[i + 0];
}
if (animpts[i + 1] > h / 2.0f) {
deltas[i + 1] = -deltas[i + 1];
}
}
gradient = new GradientPaint(0,0,Color.red,w*.7f,h*.7f,Color.yellow);
}
// calls animate for every point in animpts
public void step(int w, int h) {
for (int i = 0; i < animpts.length; i += 2) {
animate(animpts, deltas, i + 0, w);
animate(animpts, deltas, i + 1, h);
}
}
// sets the points of the path and draws and fills the path
public void drawDemo(int w, int h, Graphics2D g2) {
float[] ctrlpts = animpts;
int len = ctrlpts.length;
float prevx = ctrlpts[len - 2];
float prevy = ctrlpts[len - 1];
float curx = ctrlpts[0];
float cury = ctrlpts[1];
float midx = (curx + prevx) / 2.0f;
float midy = (cury + prevy) / 2.0f;
GeneralPath gp = new GeneralPath(GeneralPath.WIND_NON_ZERO);
gp.moveTo(midx, midy);
for (int i = 2; i <= ctrlpts.length; i += 2) {
float x1 = (midx + curx) / 2.0f;
float y1 = (midy + cury) / 2.0f;
prevx = curx;
prevy = cury;
if (i < ctrlpts.length) {
curx = ctrlpts[i + 0];
cury = ctrlpts[i + 1];
} else {
curx = ctrlpts[0];
cury = ctrlpts[1];
}
midx = (curx + prevx) / 2.0f;
midy = (cury + prevy) / 2.0f;
float x2 = (prevx + midx) / 2.0f;
float y2 = (prevy + midy) / 2.0f;
gp.curveTo(x1, y1, x2, y2, midx, midy);
}
gp.closePath();
if (doDraw) {
g2.setPaint(drawPaint);
g2.setStroke(stroke);
g2.draw(gp);
}
if (doFill) {
开发者_Python百科 if (fillPaint instanceof GradientPaint) {
fillPaint = gradient;
}
g2.setPaint(fillPaint);
g2.fill(gp);
}
}
public Graphics2D createGraphics2D(int w, int h) {
Graphics2D g2 = null;
if (bimg == null || bimg.getWidth() != w || bimg.getHeight() != h) {
bimg = (BufferedImage) createImage(w, h);
reset(w, h);
}
g2 = bimg.createGraphics();
g2.setBackground(getBackground());
g2.clearRect(0, 0, w, h);
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
return g2;
}
public void paint(Graphics g) {
Dimension d = getSize();
step(d.width, d.height);
Graphics2D g2 = createGraphics2D(d.width, d.height);
drawDemo(d.width, d.height, g2);
g2.dispose();
if (bimg != null) {
g.drawImage(bimg, 0, 0, this);
}
}
public void start() {
thread = new Thread(this);
thread.setPriority(Thread.MIN_PRIORITY);
thread.start();
}
public synchronized void stop() {
thread = null;
}
public void run() {
Thread me = Thread.currentThread();
while (thread == me) {
repaint();
try {
Thread.sleep(10);
} catch (Exception e) { break; }
}
thread = null;
}
public static void main(String argv[]) {
SignInFrame n = new SignInFrame();
n.start();
}}
In your SignInFrame constructor, you call initComponents(), but that does not exist. I think you mean to call init(). Also your JFrame does not have a size set, when I ran this under linux (Java 1.6), it worked but was tiny, you should add a setSize call.
Try it with these edits:
public class SignInFrame extends javax.swing.JFrame {
Panel panel;
/** Creates new form SignInFrame */
public SignInFrame() {
setSize (600,600);
init();
}
public void init() {
getContentPane().add(panel = new Panel());
start();
}
public void start() {
panel.start();
}
public void stop() {
panel.stop();
}
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new SignInFrame().setVisible(true);
}
});
}
}
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